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Lecture 08. The Chemistry of the Carboxylic Acid Family.

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Automatisierte Medienanalyse

Erkannte Entitäten
good morning so today I
want to begin our discussion of Chapter 22 1 in chapter 22 brings us back to the carboxyl like dancers we talked a little bit about carboxyl against Sadr's and their family in Chapter 19 and then we
started to introduce some of the chemistry of the carbon EO Group in general now of course a carbon Eurogroup is embodied in the carboxyl group of carboxyl like acids and so we
really needed this understanding to begin to proceed on so today were coming back to the carboxyl like acids and we're going to talk about the incident carboxyl like acid chemistry that involve the same type of reactivity that we solve with the tones and held up signs that is the ability of nuclear files to add to the carboxyl group and to replace a carboxyl group were going to come back again later in a couple of more chapters were restart talking about carbon-carbon bonds forming reaction to talk about place and condensation and other editions of carbon nuclear files that are going to be based on this other property of carbon yields compounds the acidity of the Alpha Prime Time for right now we're going to just talk about the carboxyl extensive family and their properties the different functions the different
members of this family and their Inter conversion and today will conclude by discussing the chemistry of acid
chlorides and drive the 2 most reactive members of the carboxyl against his family so let me drive out the family here police the main members 3 important players of course we have carboxyl again since and then sort of it as a I'm very close closely relationship we have master's we've already talked about the relationship between alcohols and and water and hearing carboxyl like gas is used for heavily half of all water molecules and Esther you have half of an alcohol molecules of the many things in common and the standards of various flavors I'll just 2 of the and structure generically with you sort of generic our groups stated the alkyl they can be aromatic taking the lead in the hydrogen some we have various flavors of and primary secondary and tertiary and it will talk a little bit more about them and is then moving moving along in the family we have answered the chlorides acid chlorides Avery reactive will be talking about the chemistry and giving you the important members of the family 1 could easily envision acid bromides the bromine is replaced with a chlorine and perhaps envisioned very similar properties in practice there much less commonly encountered that very similar in their reactivity acid iodide Stephen Moore more than usual and more reactive and fluoride that funny we're not going to talk a whole lot about them they're still quite reactive but actually a little less reactive acid Clerides for reasons of resonance stabilization also In the reactor members of the family we have an hydride sometimes you'll hear them referred to as acid and hydride and finally and again of course I'm only taking a limited subset of the family we have nite tree also and if you look at the and tree the trail is sort of the odd man out in this group in the sense that you would say you would say by comparison ideas from writing everything with right carboxyl against its by comparison it doesn't look anything like the other members of the family it's sort of the odd
because and that what is in common to all of these is that the oxidation state of the carbon atom is the same in
all of these in all of these family members were in the Plus Three oxidation state for that carbon so even know lower carboxyl like and during the chloride and and hydride have carbon your group's carving double bonded to oxygen in the nite we'll obviously does not share many similarities and reactivity also will we talked about it means I said that in in many ways the reactivity of carbon nitrogen double bond is very similar to a carbon-oxygen double bond in other words means to have a lot of the same activity is Alden hides in key tones and nite trails now you have a triple bond together and get this theme of a provision called the police from his and his face was that otherwise scuffling to an electorate negative Adam alright let's take a moment to talk about naming compounds and I don't wanna get heavily caught up and I think it's very easy for students to obsess about nomenclature and I want you to be able to see the forest for the trees I really want you to be able to see the anatomical features of the molecules in other words the able to recognize the pieces of the molecule because conceptually this is the key to understanding the molecules and it's very easy to quickly end up getting yourself in the hands of alphabets is helpful politicization and so forth so here we have been tested and Esther as I just mentioned has 1 company that comes from and answers and another company that comes from an alcohol and just recognizing those 2 key components that is key to understanding the
synthesis of some of their reactivity and so forth on so let me take a specific gesturing we can see how
to name it and so there's Seth Oster has since tested components from you know at acid and alcohol components from ethyl alcohol ethanol so we call this Ethel as the state of 1st Lehmann a last name we call this asshole you turn away it kind of makes sense on the nomenclature intuitively if you recognize that what we've done is just take the Buellton nowhere to said and replace the OIC will always tree and so they're being able to see the components is important but give us another example along the same lines so we call it ,comma Hong compound that there is a way of it's always seen on the end because it's derived from bins tested at 4 AM it a lot of the I'm a lot of the thinking is is kind of similar we have we have to components and we sort of recognize that here's our standard and so we have a component that came from the S & born in that came from intermingling ammonia and so on give us a couple of examples here no way you can think of this as being a parent compound in the sense that this is sort of the Paris any thanks in no way an acid derived damage that would have a nitrogen on it whether it had substituent certain so we would call this text sound emitted from the and you can just think of this as basically putting an ad on the so it's derived from Hecht's no way answered so we called we call this a primary and made the of derived from pneumonia because they're too when they choose to hydrogen cyanide institutions in of give us an example of another animated let some facts and give us an example of a couple of more and the start on this flight within Europe you we are a couple a couple
more examples here so this is an asset this standard comes from a acidic against said so we would call this NFL a set of this compound is a secondary amid I mean if you're typing out the structure you would I italicized the in In the end means the Adam nitrogen it means that there is a methyl group from Adam nitrogen and so unlike the lowercase and when I talked about staying in lithium which would normally little the linear chain with capital and as I said I'd said I felt like I haven't written life as reported here means on the nitrogen atoms take another another example of the year common anonymity that's often used as a solvent is in n-dimensional former mayor and so we have to work 2 nights to substituent under nitrogen so we call this in in time Nathalie formidable all 1 word to tertiary hammered in other words it has to substituent on the nitrogen and 1 thing to keep in mind many many students look at a compound lifetime methyl former bed and they say Oh it's an out because I'm used to the CHO grew well the nitrogen and the Carbondale function together the fear the work as a functional group in other words we see a functional group 1 of the driving concepts of organic chemistry is that groups of Adams closely connected also often have very specific properties because the nitrogen is conjugated because of the presence of talk more about that moment because it's in resonance with the carbonyl group this behaves like an animated not like Imelda applied in all of its reactivity so just as Annapolis sediment and therefore was said and that is not a key tone in n-dimensional former is not now that it the real world are OK great question Are is the proper names these the company's annual 1 answer come so so that's why would the NFL found embedded if I wanted to ride out the idea of pact name just as we have done their with taxonomy but no self-respecting chemist with and that the latter 1 would be an end died methyl met standard because it's derived from math and nowhere acid but everyone calls it formic acid we learned your right we will be go on the that as I said students often obsess over nomenclature you would be hard knowledge OK and it's scary it's scary because I literally can hand about 500 pages on how the name organic compounds and it's easy to obsess over at the
other reason it's easy to obsess over this is because when it comes down to it this is simple I don't mean it's simple to know all of the roles and some of them are working I needed something
that a computer can easily worked through and there's very little Lyra thought processes involved in naming a compound and so it's easy to spend time obsessing over that and not to get onto the stuff that's really conceptual so don't worry I won't ask you out test was that the idea packed a were the common name sorry now about giving 1 Algeria 1 thing then I wouldn't expect you to obsess over but I was I was obsessing over just to show you will show you 1 of the for example of where we have 2 different substituent here so this is another tertiary Ahmed and for this particular when it actually was an example from your book it's can find subdued and in a break with the -dash here just because I can't write it all out on 1 line in and then what surfer finishing 1 2 3 4 5 10 10 and I think you textbook must've had you ongoing and brought with when you were carving here you tuned in and that was in fall from the problems that I ask you to work out as you go along with new working out working things out anyway what we've done here is we've named the 2 halves of the nitrogen without held the title but then I think it's really really easy to end up obsessing over there and they don't get that obsessed alright let's go on to acid chlorides and answered and hydride virus so let's go on to an innocent chloride here derived from Nintendo answered and again we're seeing the family relationships here to this is an acid chloride derived from Pantano again said so we call it tend to handle for either of the taking the independent nowhere of the acid from which it derives we changed it to always Hawaii L with a common names you do it slightly differently so this compound here these assets TO chloride but rather than assets Howie young chloride it shows just how people name and how it flows off flows off the tongue in let's do 1 more of doing and hydride here this is the and hydride derived from this is always there said so we call it bends away and hydride about it but the IRS last class
of compounds that want to talk about in the family is nite trails and so I'll
just take the nite related to Hexham way gas is the 1 that has 6 carbons hinted that he might like to see triple bond in you might draw Justice and it's the same thing this is called hexane 93 all of those sentences expire been chain it's called hexane and you just nite tree-lined it you don't have to specify the position of the nite real because being Tripoli bonded there's no other place that you could put that right through group except on the end of it again the small molecules tend to have a common names we also intend to splash the small molecules around like water in the
laboratory as CEO Night Trail is a common solvent This is a don't nite trio as the tone is a common
solvent CD is opponents all and so you splash them around in the separate quarterfinals Indian chromatograph columns and the like analysts say give you 1 more example so 1 of the things that we saw we were talking about naming God carboxyl like acids was weak said when you have different groups some of them will have lower priority so in general carboxyl like acids have higher priority than key tones and held up signs and nite wheels have lower priority even carboxyl against so you have this idea that if you have a nice real group and an innocent man you end up naming it as the substituted answered so this 1 is common with called sigh and oversee the destiny of of of of oracle back there any kind of a quick overview of how we talk about these compounds I wanna talk a mail about their physical and the spectroscopic properties because I think that gets us into the things that are more interesting and more important Europe textbook sort of approach is this from the point of generalities and I decided I would approach the approach our discussion today of the physical properties of compounds from a couple of specific examples that were kind of important compounds so Palestinians this is maybe giving you a little bit of a flavor of my own thinking about the chemistry of asked of the carboxyl against family so I decided to start our discussion today with ethyl acetate ethyl acetate is of course the widely used solvent present in nail polish remover you may have used it for liquid liquid extraction in the laboratory esters in general tender have rather nice fruity odor and so ethyl acetate has a strong smell to it that's not on unpleasant and some of the asked some of the Astors like ISO animal acetate have very strong fruity just over the powering Levan and that's 1 of the components in the Nunavut so Apple acetate is a liquid that has a boiling point of 77 degrees Celsius and I thought that might be nice kick off .period to kind of contrast some of the properties to other other molecules and so what I was thinking about molecules that are kind of kind of the the same societies I figured well Apple acetate has
6 heavy Adams 6 carbon and oxygen atoms it's about the same molecular weight as
hexane sold by comparison I'd say taxation as a liquid 69 degrees is its boiling point and then if you say Well we learned when we talk about better walls contacts that if you have a more linear molecule you get more than the walls contact and cost of velocity as you might say would be a better comparison to comparing it the 2 Mathilde painting into Mathilde 10 teams also will acknowledge that it has a boiling point on 60 degrees and so the detailed ,comma message on on this is not surprising alas Tate has a higher boiling point then molecules of similar size that don't have died polls in which it makes sense I mean you have a molecule that has a
molecular dipole ended and as a result you off also see differences in solubility on and all of this really can be
explained by thinking about residents structures all just added that the solubility is insoluble in water soluble to the extent of about 8 . 3 grams per 100 milliliters finds find that that sort of interesting I'm on the 1 hand you expect that velocity to be had solubility and what we've learned that if you have polar Adams and you have a reasonable ratio of polar Adams to carbon groups you should have some solubility in water and at the same time it heard the number
for war that if you have more carbons proxy general few work you can think of something soluble but here we the way we have to province for oxygen and see think about something like ethanol and it's municipal with water it mixes with water so to province 1 oxygen therefore carbons 1 oxygen is about the same solubility in water but here we have 2 oxygen and tech growth and for carbons and 1 oxygen is
completely invisible with water so so it in a way that surprises me it's a little less soluble than you might like the Indians we we certainly didn't think of it as color and you can think of it either as all the other bond between oxygen and carbon is polarized and so you can think of it as saying dealt the plus health the miners or you can think of its behavior in terms of residents structures and so just as with every carbon Neil compound you can write minor resonance structures in which the park beneath Minor resonance structure in which charges separating like the old man guests of the good person drawing the over here what's interesting about philosophy take and all other ancestors these you can write a 2nd residents form like so the positive charges this oxygen and so collective lay the major residents structure and a minor resonance structures the small contributors but certainly can explain the polarity of the molecule just as we saw in explained that acetone had a higher boiling point and say I said dueling and yet there's a little bit unsatisfying why it's not more polar the 1 thing that these residents structures don't really embodies is the fact that this oxygen is well it's donating electrons through resonance it's also pulling them away in the sigma bond so in other words we have these 2 oxygen is pulling in opposite directions through the signal bonds to pull electrons away and for that reason at the last take isn't as polar as you might otherwise otherwise they know the words soluble in water but it's not super soluble in water inadmissible when in water feeding it has be same polar molecules that has a dipole moment from a dipole moment is not used did it's not huge is the kind of form and if we don't talk to to you about the moment when we talk about talk about family alright I wanted contrast Apple acetate as I said I'm coming at this from the point of view of specific molecules and their properties and sort of what they what they mean to me I want contrast ethyl acetate to a couple of familiar image is so I'll start where a set of mired in so as surmised by comparison is a solid start a melting point of 82 degrees and if you heated enough so it boils it has a boiling point of 221 degrees so clearly a set even know it's the smaller molecules anaphylaxis take is much stickier and we saw this principle and carboxyl like acids when we talk about their their high boiling point last Saturday has the ability to hydrogen bombs so you can form hydrogen divers in you can get further hydrogen-bonding because you have the negative nitrogen bound to the hydrogen and so that can make these these molecules stick together a mail dynamical former made of course doesn't have hydrogen bonding you don't have any hydrogen cyanide regions In so doing medical former made can participate in hydrogen bonding and yet it still is much higher boiling then but then ethyl acetate so medical former made is a liquid boiling point is 153 degrees the decomposes to carbon-monoxide and methyl Amina at that temperature so you can't really distillates and it's much more color it's got a bigger dipole moment bigger dielectric constant then ethyl acetate it's admissible with water in newly only in the face of dire methyl formate can think of it getting a lot of its properties from that minor resonance structure off on the right I'm not going to write off the wall of the residence structures and just going to ride out the key resonant structure here and say you can explain a lot of its behavior by this this type of resonance structure now this brings up an important point about damage to this is still a minor residents structure but the point is the molecule is always out get to your question and the 2nd molecule is always multiple residents structures of all at the same time needed just different pictures of the same thing but in the case of Apple acetate it's
just a little bit of this resonance structure and in the case of gunbattle former mayor told that more it's on the order of maybe 30 per cent of that residents from he needed to have a number in your head is 1 of the things that vary important to keep in mind about this fact is the fact that this nitrogen being dimensional former made at average in general is much closer to being asked the channel and its properties to be as veto hybridized and asked it to reignited eyes letter writing it as St chill hybridized here because that means ,comma like as the closest description it's somewhere in between but it's more like as the 2 were hybridized in other words that nitrogen is
not basic like mean it's much less the basic invented the meaning because it's participating in resonance fired I saw a question 1st not decomposes DEC is often the shorthand you'll see chemists right for decompose is another question we have to Pentre known to pentanol let's see it's acetone boils at I think 56 degrees so we're talking somewhere around 80 years to await Penton also I'm thinking you know so painted known yet close to 100 degrees so yeah I mean it's even a bigger bigger dipole for there but the point is if you look at 153 versus 77 and it's a big difference so in other words ethyl acetate a polar molecule but it's not like for polar molecules and by the time we come to the Hamed's there really is no .period polar on if I wanted to make maybe a closer comparison to
Apple arrived at the last 10 maybe I could also say an indictment tho was that it might just be because let's see here we have war I guess that's that's a reasonable reasonable comparison here other questions I want to take a look at this point that what the IR spectra tell us about the behavior of some of these molecules in part so you can get used to recognizing them and in part that you think continued his theme of understanding their property Our so this
separated the forest for the trees we we talked before about all the remedial compounds we talk about September delegates we talked about and except destined for rides and and hydride we talked about ancestors and and Al hides an NSC aide said and the tone and standards in their relative Carbondale stretches and No . 8 you have a obedience somewhere around 17 100 wave numbers and they differ a little bit depending on the nature of the particular cotton yield compound so and another carbon meal typically around 1660 somewhere below 1700 is difficult typically out sort of take a middle ground of around 1660 and so if we compare this I always like to think of when I hold things in my head for understanding them I always like to think around 1 compound it's kind of the same that use on the theme of Talking about a philosophy Teradyne after former made so if I can't think of a typical the town whether it's like hacks and all owner acetone and I sort of think of a typical tone as having about 1715 wave numbers and so you think about this and you say Well this is saying is that the nite proves that the carbon-oxygen double bond stretch is weaker then head of 82 so I'd say week here CEO and you think about this resonant structure and its minor resident structure really helps explain and very nicely in other words of course it's not 1 of top 3 other it's bold and other relevant structures at the same time but if you look at this you say only I can understand we have some single bond character mixed in here with a double bond characters so instead of vibrating at a higher frequency like a stiffer spring it vibrates at a lower frequency ever so slightly lower like the last spring out we come over to ask there's typical as the Pentagon is a sort of generic compounds and generic values the typical Leicester's at about 17 30 find for the carbonyl spread so you don't see you don't see it very very different from the town just a little bit different but where you really start to see things differently by the time you get an acid chloride and Anderson and hydride and this is where I think it's really telling so you look at acid chloride and the
Carbondale stretch now isn't about 1800 and if you're working and I are expected it's 18 hundreds really distinctive another word 1720 1735 you'd say OK I can see differences I can read the scale but they're all sort similar and the sale of 16 of 50 1660 1678 say that significantly different than at the other end you looking it's 1800 that really starts to look different in 1 of the ways you can think about is there a couple of ways you can think about it so obviously the fact that
we're at 1800 means here we have a stronger CEO blond Montoya can think about is without residents you can say well chlorine is electronic you can say chlorine is elected negative and has appalling Elektra negativity of 3 . show and it's basically pulling electron density down and the big difference between chlorine an oxygen is not singin is the same role as as carbon oxygen can give good resonance overlap with carbon Lorain instead of being 2nd row with 3rd row it's 1 road down you can't get much polite bonded you end up with variable double bond character but a lot of that signal like from withdrawing character a lot of the inductively electron withdrawing and so you can think of the chlorine as calling electrons down from the oxygen making this bond stronger it's polling electron density down you have long pairs of electrons here pushing back here I like to win the back of my mind that PRI would write his resonance structure say elsewhere but in the back of my mind I kind of keep in mind the fact that if you take that kind of thinking to its logical extreme and say All right there there is a component of the chlorine pulling electron density away inductively you can think about this nonbonded residents structures here in this northern non-residents structure you have careful Bond character in other words this is a very minor contributor but is basically that oxygen pushing an extra electron density making that carbon bond even stronger if it's stronger you have it resonate at a higher frequency and so you end up at 1800 instead of 1700 wave numbers but also
very hot electronically and we're going to see that acid chloride so the most reactive member of the family would nuclear files so now you have the the
same type of principle it and hydride so just like the chlorine is pulling away electron density you have the ASO group is pulling away electron density and for that reason answered and hydride the carbon stretches also come at a higher frequency than you might expect for safety tone and arson and hydride show pairs 18 20 inch 1760 would be typical for a pair of hands in the eye on another word unit choose directly is not wine and at 1st you might say Oh well that means that there are 2 types of Carbondale groups it's not really that simple when you have
vibrations and their close together you get water called couple
vibrations when they're close to each other in space is kind of like splitting Indiana Morris spectrum and win the vibrations couple you have them working together in other words it's not 1 Carbondale stretching and the other Carbondale stretching but it's both of them stretching together and type of stress is 1 of them is an asymmetric threats and 1 of them is a symmetric stretched so you end up with 2 hands but but but but but but but but but all right and so I think what they claim are expected really you're telling us is that answered chlorides
and that hydride really special in their properties and their special in that you have a lot of extra electoral Felicity at the carbon meal in other words held high
in other words acid chlorides an incident and hydride reacts with many different electrify because that party also known as the polling away the electron withdrawing troops of the ASO groups are of the Chloride Group so to to put it bluntly if I take as a shield chloride and I poured into water but it says a lot about the latter's reacted violently in reaction gives the CD dances and ACL after Anaheim grinds also reacts with water but not as violently but they react others right reacts by contrast violently in the scenic and hydride hide Reliance's idolizes is a fancy way of saying Cleaves licenses by by water and where I really wanted compare compare this to start our fashion all the chemical reactivity of the
chemical properties of the carboxyl again a family where I really wanna contrast things to do is the start to contrast the
interstate asters and image so played together velocity in water there's no reaction at the at the Palermo later of how we can hide relies on velocity with water but it doesn't occur by just mixing at velocity and water had while apply that aching power over a very very very long period light years Europe could occur if you only if you
weigh only after last taken water but for all intents and purposes there is no reaction and that's a very good thing because ancestors and which our
right as the next molecule right Diamond Hill was set at nite these are the molecules of biology not at velocity and I'm at was set amid the blood of course testers make up your leopard that membrane in Europe that covers every cell in your body is made of liberate lipids made of long chain fatty acids that arrest applied to glycerol better hope to other fragments like single call and what would happen if at room temperature at 37 at body temperature Astor's reacted with water is yourselves would all be little also break apart so it's very fortunate that Astor's don't automatically adults without a catalyst or an enzyme react with water at any appreciable rain at room temperature of 37 Celsius and ends at the same time if I'd taken ended with water there's no reaction and again this is very very important because all of the proteins in your body are made up of added that if they were to react with water at the proteins would break down just be a pile of amino acids fatty acids and and glycerol and you wouldn't they you know that esters are also widely prevalent compounds not only naturally synthetic away your nylon backpack is made of a
Pollyanna that tennis made to mimic proteins and initially the proteins itself because stockings as I see you're wearing are used to being made are only available in silk and silk is expensive and fragile and at the time of World War Two was needed
for the war effort and so having synthetic substitutes was useful to Astor's again brand very good thing that polyamide it's like your backpack don't hide relies when it rains your folks would fall out and get wet and polyester is in addition to its polyester fabrics if you're wearing a polyester warm-up jacket there are made are used to make your water bottle and Europe plastic many of the enterprise polystyrene in Europe container of crime by your water bottles that you've the Aquafina or whatever horrible water they sell on campus here are are buried investors it again you'd be in a lot of trouble if they hide relies on their own while the at all you have with the man yes and we will talk about that in tomorrow's leaders next thing our subsequent talk here so yes indeed bastards and strong basis and they can make them react I wanna
finish 1 discussion of spectroscopic properties before moving on to chemical
reactivity and focusing on acid chlorides and hydride and I want I want to include maybe by talking about a single nite real here and nite trails in general so we talked about all the carbon yields to me said carbon-oxygen double monster center around 1700 wave of tripled on the course stronger than double bonds carbon nitrogen triple bond is centered at about 20 to fit anyway numbers usually shot in the eye or a spectrum of the long as we're talking about a Seder nite we'll all end also no reaction with water from the hinted that in the absence of strong acid a strong base and will be talking about that later I also want to give you a generalization remember we're talking about an Aymara before and I said I like to have a few baseline numbers in my head that methyl group whether it's on at scene of a single nite trailer next to any sort of carbon all these methyl groups are always about 2 ppm very close to 2 ppm in the one-day genome the 1st time in more March than the reason I like to keep that number in mind is that I can think of OK if we have a methylene so just like methylene an alkyl chain is a little further down the field a few more tents downfield International group venomous sign in an alkyl
chain is a little further down the field we can go a little further down the field so in general you can say
for a hydrogen that's next to what Cardinal or next to a nitrogen in general about let's say tuned at 3 ppm at 2 2 2 we find ppm depending on how you want to look at it in other words and naphthalene a H 2 is going to be a few tense further down the field of signs will be a few tense further down the field I don't want to get overly caught up on the Tomba's here 1st of all all I just want to mention a few things in the carbon 13 cotton meals in general are way down field of the animated region of the aromatic region so in general you can pick out carbon meals cotton yields in key towns in our behinds typically around 200 ppm a low but more to 20 190 somewhere around there typically the whole carboxyl like acid family were talking about 160 to 180 ppm of fin-de-siecle 13 and tomorrow the whole sort of carbon the whole ,comma Boccella gas and family and just for the sake of completion of the review nite trilogy of carbon-carbon triple bond it's kind of like an alkaline but you haven't Elektra negative ad so you're talking about 115 to 120 ppm yeah organic chemistry is about making stuff at least a
big part of it and there are chemical reactions take convert all all of the members although the carboxyl like acid family acid chloride acid and hide rides
Astor's carboxyl like NSC aides and the kids and even nite trails can be injured converted to other members of the family good tonight trails that Astor's to carboxyl like acids that acid chloride said acid and hydride now if I were to to say OK how many different just like Figure 1 reaction for each of these and I think I've named 6 members the family going into any other 6 members of the family I basically would end up having a minimum of 15 different reactions and their cost more danger convert these members of the family and so the 1st thing you might think is 0 my God this is overwhelming how can I possibly understand all of these reactions at all Of these reagents and the answer really becomes bike thinking mechanistic fully understanding the principles and understanding the general reactivity of different molecules so I wanna give you some of the generalization here before we dive into specific in so you can have some general member of the family nite trails the kind of also I'm gonna leave them out will talk about them at the at the end of the next lecture and we have some nuclear file a new willingness or anything new at the a sort of a very very generic type of of species water of course was a new H it was always H H in general a common theme is that the group on the carboxyl against acid under some conditions get replaced sticking get displaced by a nucleophile and if I'm going to write a balanced equation I would also say plus X minus were in excess of the Nets not meant to be
a functional equation at this point this is this is meant to be a generalization and now I wanna start to put structure and some specific status In so what I would
say Is this occurs with basic nuclear files at about so in other words species like al-Qaida outside of moral blindness hydroxide age-old Linus always each minus and let's say a means of all right it is all odds UNH but I'm not meaning specifically a secondary Amin I could mean of primary right could mean pneumonia more so in other words in general members of all the carboxyl like acid family in general 10 reacts with good news with basic nuclear files or we put electoral files at the end of course water Wyoming by good electoral files will grow like profiles are those ones that sends all will react vigorously rejected nucleophile so specifically in this family I'm talking about acid chlorides and acid and hydride but but but it was clear that sort of wonder 1 generalization that I make and the other a generalization that I would make that we only basic nuclear files also the water on the biweekly basic nuclear files what we
talked about this with key tones and without the heights were talking about things like alcohols and water all right for all
ages and water and also that they can react but we less reactive Electra filed at the waterline mean by less reactive electoral Wild well I mean the members of the family said don't react with these that don't have that electron from withdrawing group that don't have that problem deals shifted up the 100 their ballots in the IRA spectrum so we're talking ancestors the acid Hamid's a nite to Real's the 18 and they can do this if they have some help with strong acid catalysis at the end of what we're going to see In the next lecture is that a strong acid can probe made the carbon yield of and faster wore a carboxyl like said war in and work in progress made a nite Trudeau group and take something that only a week electoral and turning it into a strong electoral filed In a mechanism that we end up going parts of the generalization serves as a framework and now I wanna go on go on some specifics and to talk about specific reactions of acid chloride and acid and hydride and sold by way of a specific example altogether Sotelo chloride what a writer balanced equation here at City of chloride let's look at its reaction with a simple that belong landing in Cincinnati OH chloride can react with 2 molecules of Madeleine Maine 2 years ago bullish sentiment organic chemistry always is that about balancing the equations but I will balance said and Diamond Hill ammonium chloride diner full immunity hydrochloride MPEG-2 and to lost CL minus as
assault 1 I want us to to be able to do because this is the archetype for all of our thinking about this chemistry I want us to be able to think and understand our way through these mechanisms and particularly to
get the big picture because sometimes the details aren't going to be that important soldiers arrested till chloride we know that that Carbondale is electrical and we know that Diamant methyl Amin is nuclear like it has a long parable lecture finds it once it's willing to share those electrons we can attack very much like the thing we saw in the mean information chemistry we can attack this extra Elektra fell like carbon meals and at this point like this I write this as
irreversible is always a little bit of a judgment call but if you have something where you're really take this I can write
the 1st step is reversible although honestly American it's what about it so I'm just going to write this right this 1 was OK so at this point tho the big picture of the big idea is now just as in the mean formation at this point formed detector he evil species we formed a task Tunisia and death and the next step
relayed from the big idea here the
next part of the yes Hopes did I forget nature of life during an extra here you may hear not when we're all old "quotation mark OK I was I was meaning to I'm sorry people I was meaning to draw dime so time let's do 2 molecules we that go with that kind of thing that let's do 2 molecules of dying only react to form the dimer for 1 minute and I met a woman in world-record time almost all ride and let's have our 2 mouthfuls of on the nitrogen with a hydrogen alone add to the Carbondale attacks to give the territory intermediate and that figure .period about this is our territory and rolling through media is going to be unstable just as we saw in the main formation where they have Miami now is not a stable compounds not and I solve all found that same theme emerges here the question of what the year-ago SAY going into our global it's great flowering just as in the meaning formation of the factory Heberle intermediate is unstable I'll be a good person for 1 moment here and adroit in all of my charges and all of my lone pairs of electrons detectors growing your media can break down it doesn't sit around getting kicked out chloride fluoride is a good leaving group but fluoride gets expelled but remember this
nitrogen in here didn't have it is not the enemy nitrogen it is not a basic nitrogen it is not
nasty through 3 nitrogen it doesn't want to have a proton on it it is very acidic and it's going to give up that Proton to anything that's basic and we have done that Colombian President and so are dying at alarming is the strongest base in the house and I methyl meaning there is going to pull off that protons to give you you're dimensional Saturday was dying methyl ammonium fluoride and my guess is already written my fluoride soldiers found demonstrate exploration and say plus the diameter of the product and if I were to not have that extra equivalent of dynamical Amin around halfway through all of my died baffled means the remaining die methyl meeting would be proud native has the hydrochloride now the reason I'm saying not to to get too bent out of shape on this
mechanism the big picture nucleophile attacked we get attacked the during the tendering evil intermediate breaks
down proton shuffle around you textbook writes these 2 steps in reverse or more specifically your textbook on closely related reactions and the homework right that the probe nations that advertise for his immediate I don't think that makes as much sense on the basis of acidity don't get bent out of shape about it 1 way or another the picture nucleophile attacks territory Negro intermediate flakes down Proton shuffle around the the shuffle around for him and it's not that big a deal other big-picture items from a sympathetic to interview chemists often want to go ahead and not waste valuable Amin sometimes they'll analyzes of data that sacrificial at tertiary Indian like triathlon meaning for parenting is added as a basis all )right parenthesis parenthesis period in here is added as a sacrificial base so you can use only 1 equivalents other means of but some of the Our this scene basic principle of reactivity of massive chlorides of applying at all other species whether rates a strong base would its basic
nucleophile most likened the USA weekly basic nucleophile like alcohols and water acid chloride still react vigorously
so for example if I take Denzel we'll chloride and I take ethanol the reactors like I said acetylcholine ride reacted to form following water they react form and asked the Apple bends away then again if I want a balanced equation HCL would be a byproduct very often in this chemistry as well often yield use pure Dean as a base but of the period being triathlon means can be used as well the isopropyl at million well to react with the HCl of just sense of writing a balanced equation if like take liberties we'll chloride plus ethanol the plus Fiorentina on didn't go ahead and get Ethel Denzel late last year in the numerator chloride In the prep at every level in the laboratory would probably carry out in a curious worked out in a separate Tory final in which she would extract the Ethel bends away into you're organic phase you would wash away the
period biennium hydrochloride sold immediately estates and then we would drive the organic phase over Max sulfate and Delta
concentrating on the left you can imagine all sorts of other reactions of acid chloride we already saw the audacity 0 chloride reacted with water to
give acidic said you could use some sodium hydroxide in there to get ethyl acetate out of their sodium of sodium acetate
out of there you could react sodium acetate which acid still chloride to get acidic and hydride and so maybe I will just very quickly sketched out these reactions as an fluoride was staged to all those who receive advance the what's CDL as your chloride and you should be able to think your way through mechanistic equally all of these tests until chloride .period to hydroxide and those ascertained and I plus water it's chloride an and I'll just try 1 more balanced equation in city of chloride last let's say sodium acetate just for the hell of it all right in the counter ion euros still wants to assume economy drive for us and for our right and despair as all of the reactor is sound there actually all the same basic principle once you get the the idea of a nucleophile tapping your acid chloride to form detector here on intermediate detect intermediate breaking down and some Proton shuffling around you wind up comfortable with all of this chemistry and you see that it's really really falls into the same category I wanted to mention 2 last points 1 of these is the trends we've been talking about recent that animosity of chloride is more reactive were in general ,comma right answered rides or more reactive than an arrived rides and those who are more reactive than esters and those the more reactive than this and that makes sense if you consider the PKK and all conjugate acid of the leaving that no other words HCL is the conjugate acid of chloride as a leading group it's PTA is negative 7 In other words chloride is a very good leaving group even in this era in this edition elimination and the group the PKK of carboxyl like the conjugate at base of carboxyl late leaving Group Anand hydride is on the order of the Board of while it's much less of a good leaving group in chloride remember
this is additional emanations chemistry not us into displaced the chemistry it's still a good enough leaving by the time we
come to an alcoholic conjugate base of Alcock side leaving the was talking to pay 16 of the 17 here now were not so good and by the time we come to In meeting as a leading group you worried about the Pentium which number used new textbooks about 38 cents and now
we've done we've basically spanned 5 orders of magnitude here in our in our peak hour power Skip Spence they are almost 50 orders of magnitude here 45 orders of magnitude in our chemistry here are the
only sort of of in in this next part carboxyl against and the reason I haven't immediately included ministers there's 1 special caveat you'd say for many purposes and see Fisher's terpretation transistor fication actors carboxyl a gasses are the same but in the case of all this so often you will have a base the probe made carboxyl like acid to give you a carboxyl late and then you went up really since the carboxyl aghast that is acidic you really have to think about it moved to wine which is just not a leading group so there's certain cases where you're talking about say an estimable react within the meaning if warm but a carboxyl like acid is just going to do proton transfer with me last year he the hell out of the thing to 200 degrees are the the last thing I wanted to is talk about the reactivity of England rides and really for many many purposes the reactivity of and rises is like that of chlorides acid chlorides except they don't sizzle with water so there's less reactive sulfide take a seat at the end of my driver and I Madeleine being that the general right of balanced equation idea design that set up thing and I also get was going full ammonium acetate by the way you will often see this written as a seat again hydride too old and sometimes you'll see a written here as an ABC group but handsome just like year as a way now for the same reason and the same idea we talked about when we were talking about the chemistry of acid chloride because you're using a 2nd equivalent of Amin as a base in this chemistry because it's getting program mandated by the acidic gasses byproduct of
reaction often you will use a sacrificial bases like purity it's
all right a balanced equation at this point use this shorthand for a CD can hydride so alright acidic and hydride was met on the eve of cluster period leading what you would see reagents written above an arrow goes to war the please see St. part here and then if I want to write a balanced equation in India .period unionists take as my says guide product and all Of these principles
of reactivity then applied to things like alcohols as well so take a seat again hydride and
ethanol and again I'll just use this common shorthand for acidic and hydride plus ethanol just as we saw it reacted with water to give acidic gasses acidic and hydride reacts with ethanol to give at velocity and again there are many ways you could right after last Tate Aldus right here only the it was the wage of alright so I
think that gives us a kind of an overview of the reactivity of the
mostly active members of the family audiences chlorides and hide rides as well as the general properties of the family will talk about the reaction of acid catalyzed reaction with weak nuclear files for as is and carboxyl like acids as well as the effect of a strong nuclear files like faces on them next time
Chemische Reaktion
Chemische Bindung
Fülle <Speise>
Elektron <Legierung>
Bukett <Wein>
Weibliche Tote
Physikalische Chemie
Setzen <Verfahrenstechnik>
Gangart <Erzlagerstätte>
Spezies <Chemie>
Amine <primär->
Dipol <1,3->
Chemische Struktur
Sammler <Technik>
Aktivität <Konzentration>
Chemischer Reaktor
Eliminierungsreaktion <alpha->
Chemische Eigenschaft
Kettenlänge <Makromolekül>
Hydroxybuttersäure <gamma->
Single electron transfer
Quelle <Hydrologie>
Bukett <Wein>
Gekochter Schinken
Advanced glycosylation end products
Funktionelle Gruppe
Containment <Gentechnologie>
Aktivierung <Physiologie>
Gangart <Erzlagerstätte>
Hope <Diamant>
Organische Verbindungen
Chemische Forschung
Chemische Verbindungen
Chemische Verschiebung
Gesättigte Fettsäuren
Einsames Elektronenpaar
Potenz <Homöopathie>
Substrat <Boden>
Chemischer Prozess


Formale Metadaten

Titel Lecture 08. The Chemistry of the Carboxylic Acid Family.
Serientitel Chemistry 51C: Organic Chemistry (Spring 2012)
Teil 08
Anzahl der Teile 19
Autor Nowick, James
Lizenz CC-Namensnennung 3.0 Unported:
Sie dürfen das Werk bzw. den Inhalt zu jedem legalen Zweck nutzen, verändern und in unveränderter oder veränderter Form vervielfältigen, verbreiten und öffentlich zugänglich machen, sofern Sie den Namen des Autors/Rechteinhabers in der von ihm festgelegten Weise nennen.
DOI 10.5446/19412
Herausgeber University of California Irvine (UCI)
Erscheinungsjahr 2012
Sprache Englisch

Inhaltliche Metadaten

Fachgebiet Chemie
Abstract This is the third quarter course in the organic chemistry series. Topics covered include: Fundamental concepts relating to carbon compounds with emphasis on structural theory and the nature of chemical bonding, stereochemistry, reaction mechanisms, and spectroscopic, physical, and chemical properties of the principal classes of carbon compounds. Index of Topics: 2:00-Carboxylic Acid Derivatives 5:54-Nomenclature 17:44-Acid Chlorides and Anhydrides 22:28-Boiling Points of Esters Versus Alkanes 26:22-Resonance Structures 28:59-Properties of Amides 35:12-IR Spectroscopy 43:51-Reaction of Acid Chloride and Anhydride in Water 45:05-Reaction of Esters and Amides in Water 51:58-NMR of Carbonyls 54:51-Carboxylic Acid Derivatives and Nucleophiles 58:08-Weakly Basic Nucleophiles 1:00:49-Balanced Equation Example 1:05:19-Student Question 1:09:28-Acid Chloride Reaction Example 1:14:11-Relative Reactivity of Carboxylic Acid Derivatives 1:17:44-Anhydride Reaction

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