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Lec 14. Alkali Organometallics (Pt. III) & Lec 15

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"quotation mark when we left off on now on Friday the women talking
alkali metal organic metallics alkalinity and potentially a local sodium potassium you won't see those without themes you'll see a lot of time and we brought this problem that alkali metal organic telex aggregator they always aggregating solutions they don't exist is monomers even in teacher which is coordinating solid this demand of lithium ion for extra electrons causes it to do this weird stuff so if you put the lithium in ths it adopts the human shapes structures that's the structure of the lithium and teenager it's equilibrium in ths with this dynamic form semantic Hubertus square so each Beutel lithium each carbon atom here has not just for bonds but find bonds to the carbon atoms as long as it doesn't violate the act will that's OK so you can see what's happening because of this demand the behind nuclear Felicity this common with him on the demand of lithium to satisfy the act will you get these weird aggregates so this is not the exception this is the and sort of stuck in this situation that we want to be truthful about our representations and so what are we going to do so let me show you some heartening stuff for for us is 0 pushes really back to study of a new straight wiser and the deals with the chemistry of the Analects so we're going there very soon get into the chemistry of bonds of the late so
a zillion things that are very similar ,comma and money point out that when you put in a little energy-related teacher ceiling with the with strong bases like lithium dies approval
image IED permeated the Alpha position and how are we going to represent this kind of lithium evenly over 99 per cent of the slick exists a diner in solution kind of like the 1 I'm showing you over there and so here's what is true if you take this new treaties with Ben's old bromide just to do an essay into 2 reaction where displays the bromide using the Lithuanian late so I guess we should draw out some sort of narrow pushing mechanism although that's not that important you could draw something like this some sort of mechanism how are we going to represent this this species this with the mean later on when in fact it exists over 99 per cent in solutions like this according to so this is
if you want to really describe what this ceiling looks like you're going to end up stuck doing something like this and I'm not going to draw the teacher molecules on those lithium so this is not a
Louis structure these are dated bonds because right of oxygen as 3 bonds don't have a positive charge since these are dated bonds in here and I'm ignoring the charges so this is what with the likes of like engages any stray wiser showed that even tho this is 99 per cent of your the late in solutions that small amount of monomer that's floating around is actually what's doing the chemical reactions another words if you want to draw the correct euro pushing mechanism you ought to be drawing them on land there even know that's not most of what what this late the nite looks like we're going to all Oregon metallic reactions calculations within the late drawing them on so never forget that these aggregates are present in entering your solution but when you draw Aero pushing mechanisms
just drop Mama and do the same kind of aero pushing the EU been doing since OPM organic chemistry found and that's going to be a rule for this class and I hate to use
this word ignore because I don't want you to ignore aggregation but I'll say for Aero pushing ignore aggregation just acknowledge that it's there mentally but when you push your heroes just roll the monomers and strong Mazari lithium from monomers of your green yard reagents from monomers looking mutilates This is the way we're going to do our aero pushing this class because on the 1 hand and again with wheat find some justification from this important study of strike while showing that it's the monitors that are doing the business work there because that's our for al-Khalifa for late I just felt among OK so it's going to cover the last little piece of a puzzle here for and this is really not an alkaloid alkali Oregon metallic but I want contrast calculate the ins and outs sodium so Bob with 1 class of organic Talic regions and that's not having on lithium a sodium on the carbon atoms it's having copper and so let's talk about 2 types of organic operating agency for the 1st time we call in or just simple organic copper compound and it looks like this so this would be a copper 1 with somehow Colgrove attached to it could be Beutel could be fennel so that's found a light-colored fennel copper and 1 characteristic of all of simple organic operators if they don't do much the death
of something very reactive to get it to be worth your while to make this
organic operating region so coppers and not very interesting and contrast that with a cool break which is very interesting and very reactive his cooperate in organic growth rate typically looks like this and that's how you make your general coporate committed the same way you make fewer than coppery agent so on organic operating you take copper bromide calculus EMU mixing together but if you add a 2nd equivalent of the Youkilis thing at all here again a agent now you can imagine how this out can again added to copper and so now you have to welcome groups uncover and he's a very nucleophilic and not very basis and if you were
interested in CC bond formation as I am and that's an interesting set of property things that are very nucleophilic and free basic focus Cisco
and talk about how uh how to think about these and I gave you a peak when I showed you that little slide show the PowerPoint presentation on Friday I give you a little peak of what organic operators look like they're aggregates worse even than these Oregon a lithium species but we're going to draw these like this if you ever need to so that this little suffix ending here 8 coupe rate tells me there's a negative charge and copper that tells me that the bonds to copper nucleophilic so it doesn't actually look like this it exists as an aggregate but you can just pretend to look something like this where added a 2nd outfield group to my copy organic operated and others to act with on their and so those bonds a nucleophilic that organic operating region so we've seen other 8 complexes like a high during a war or a digital illuminate
silicon 8 it's the same idea you consistently Felicity out of the box 1 property of coup breaks I
think I can sum this up in a simple statement of what was the only 1 with all the things that you wish Oriental Lykins would do this is what organic growth still the do substitution reactions with local he lights be efficiently open up oxides to make C bonds which al-Khalifa games do not to be the 1 for conjugate addition reactions they do listen into primary actions although Errol pushing mistakes that you make with Arianna these are the things that organic good for the take some examples of some of the things that you can do with complete and and for the 1st
of the 4 of them from the people so oppose you
want to make a carbon-carbon bond there we have lots of techniques now evolved the transition metals and and palladium catalysis but in the days before palladium catalysis if you wanted to make a carbon-carbon bond here you can just do as into substitution that sense even with copper you can't but at least when you mix lithium diphenyl cooperating here you get a very efficient substitution don't worry about the mechanism it's not assent to again very efficient substitution of that bromide and it doesn't matter doesn't have to be sp to Cedric be help heal he lied if you want to so I'm just using the final group here to emphasize that that's something you couldn't do with other regions that kind of a substitution process that's to primary actions good greater good for that period of than to primary
actions are very unusual but if you take a break reagents so
here I have bromide how formed bonds to this end carbon and not directly here to this secondary physician you had some sort of an Alcock side nucleophile American testing to primary actions out of that still led heroes do eliminations so here if you wanted to substitute this come through innocent to prime action where nucleophile adds to the end and it is Eric Cooper a reagent they prefer to prime there is my fuel group adding to the end of if I drew some sort of a mechanism for this this would be completely fictional but if you wanted to have some way to think about this Whitharral pushing I wouldn't count you wrong if you did a narrow pushing reaction even if it's completely unrealistic this
All-Star office some copper bounced to the olefin but if you did this I wouldn't complain here's what I'm thinking when I say yes into prime in case you forgot what is destined to pass it's a new attack the double
bond of looking leading group system focus those 2 examples of reactions that the rates do they open up oxides and I'm not going to draw that this is 1 of those reactions they show you wince OPM organic chemistry when they're trying to teach you a lesson to Prime is the best reaction in the world who created great and opening up oxides informing C bonds and other and other types of organic metallics indicator last major classes of reactions that complaints are great at it as 1 for addition reaction kilometres help you contrast contrasted some patterns of reactivity here if you take a simple the known and you add Anelka lithium treatment of very pure green yard reagent that has no contaminating copper and there so stirred up by adding lithium that carbon atom inoculating has a very significant amount of an ionic of negative charge if you look at the formal charges of partial negative on them on the methyl carbon right there and that makes it 1 day at here to the carbon .period preferential edition for most simple Oregon metallics ought to the Kerviel carbon and so after a while I guess I don't mean to say after the work of others as the Alcock side that's the preferred site of addition don't expect to see 1 for we call this 1 2 edition on because normally we number the carbon Sinisi known system when get a red pen here this week conceded numbering and we can remind you so 1 term for this process as we call this 1 2 additions to this scene on system for changing the bonding to Adams 1 and 2 we also call this conjugate edition as the other catch phrase for this in contrast have we had a cooperated this with the entire methyl group operate now you see only the conjugate addition reaction here this is a function of the fact that there isn't enough we draw like this and there isn't a lot of negative charge on these carbons of the methyl group that is the very those metal carbon cuts are metal copper bonds are very nucleophilic on but they're not very basic and I don't know why I'm doing this that looks awful to me so in this case those methyl ,comma attacking in a conjugate addition faction to give you this cop late and the other the other copper stuff is so what's the remainder that's floating around before I reconnect things I've got metal copper remember I said that's not very active that's 1 of the by-products and I had this lithium floating around and you'll end up with an end up with we coordination of this 0 minus 2 copper and lithium species that floating around in solution OK so fantastic reaction it it I could draw an arrow pushing reaction were simply make the methyl copper bond attack and carbon for it's not really like that and in fact the crop the copper starts off bonded pie bonded to the EU known of 5 on the season 5 on the don't need to worry about that just if you want to do Aero pushing where you just take the metal copper 1 attack will accept that OK so and let's talk about 1 way to make those reactions even better and this is more of a recipe issue than and the narrow pushing a strategy for you and that is the tram silo card is known to accelerate these additions by cooperating agency we think that but people it specifically by Kubrick and suggested he was sense for the
effect here it's normally very hard to do conjugate additions when you have this kind of dies substituted beta carbon here for having those 2 substituent really slows down additions to it's
very hard but if you had to take your standard could breed addition lithium debut will cooperate and you add in some towns and team as chloride to that it's phenomenally accelerate an otherwise slow reaction so you can imagine that the silicon is free bonding to the carbonyl oxygen making the system more Elektra and again the Mac the precise mechanism while I don't want to go through that any details simply to say that generally when you see people doing on conjugate editions with any sort of scary challenges and there was cooperated sufficiently team chloride and there in order to help you accelerate the and the product is not go there with him late you get something called a silo leading all the and we'll talk more about Scioli monitors on
later which have their own benefits for gay civil but the last sort of dramatic example of the effectiveness of this combination of GMS
chloride ions and Kubrick's breaks as even he now also how the heights are so reactive which we talked about the rates of additional Aldo hides Rosinski tones we talked about on the thermodynamic ease with which you can print lies in hides and so it is very hard to keep nuclear files from attacking aldehydes and to get them to attack at that big position on any you know and if you use this combination of of team chloride and to cooperate you favor is still favor edition on to the beta carbon Over addition to the held up so that's phenomenal it's phenomenal that you can get that kind of selectively and not attack
that elderly get 1 last sort of not alkali Oregon metallic here in this this lecture that's called outliers immortality just to get you
so I hope we you see copper attached to carbon but you don't mistake that for the same reactivity is now collecting and that's been the point here don't mistake diabolical constraints organic listings that the activities very different years and 1 last type some of organic Talic and that zinc that has none of these basis city issues of but of again 0 of lithium reagent and sold this particular example convince you that the Al closings very different they must be very different from al-Khalifa this summer to by showing you on it's very easy to make ,comma to make
acid tells us cycle proper known 2nd alone he hates to exist as the you can buy cycle probe which you can buy has tells and they're very cheap and you can even buy the
on monolith Hoxie ad out of cycle known Mom and Teresina silently that OH this is probably commercially available as well whenever I see a cycle propane and I hope you're thinking is the saying I think those bonds of so much P character I want to start using the bonds is nuclear files their nucleophilic there's lots of people characters bonds and when I see a lone pairs here on these oxygen them thinking Gee those are donating here into this antibody warble and make it and precisely on this into hills along pairs on these oxygen arms are so bring up the nuclear Felicity these 2 C C bonds so if I motorcycle probing mind was nucleophilic NIC too long period biography
that super-duper nucleophilic so you treat this with zinc chloride despite some zinc chloride sink it typically is a hydrate dry it offered under vacuum and he did what you'll find is when you mixing chloride in areas that bond that
C bondage straining nucleophilic will attack zinc chloride and so you get this very weird looking structure and I'll start off by drawing a like drawing the initial intermediate bond but this doesn't just sit there like this the important thing is that 1 of the chloride pops off madam acquired popping off and then coming back in and displacing silicon that's not a one-step process it's 3 steps don't worry about the number of steps ultimately what you get is this very strange-looking reagent to it at 1st glance looks OK that this nice sort of feel age structure in man
you can Imagen what I'm going to do with those carbon heels in just a 2nd but what's amazing about the structures that looks kind of like late but it's not an e-mail late there's an ACH 2 were
troubles ages so we can clearly see that another word I've got nucleophilic bonds and about Elektra Philip cobbles built in the same region what is amazing is that these bonds are not so nucleophilic that they go around attacking other carbon heels al-Khalifa lithium's attack esters in Carbon these carbon zinc bonds are so on reactive but they don't go around attacking the carbon in other molecules that floating rate of more than 1 of these in solution he squirms in bonds don't go around attacking the extra bonds your coverage you can isolate the statue reagent were sold 1 of his Alcatel's ingredients great for if super-duper
activated elder Hydesville attacked them if you have palladium complexes floating around in will attack these bonds will attack the palladium complexes and you can
transfer those alkyl groups to palladium that's where they tend to be useful just to convince you that these types of bonds on we are not at all nucleophilic in basic like Anelka with him so much much much attenuated reactivity it's it's extraordinary that you can add esters in the same part as those of kills Inc bonds OK so that's all we're going to say about alcohol sodium to calculate potassium calculate the amount help Alcalde coupe rates Alcatel's zinc species on and you should be on getting lots of practice using those as nuclear files to attack the torment of a major switching gears now and start talking about high bonds is nucleophile we spent all kinds of time talking now about the economy about lone
pairs nuclear files or bonds to lift you unit as nuclear files so change what we're doing what so under title
adding a lecturer files to carbon-carbon pie bonds or conversely like I said we're going to talk about pie bonds as nuclear files and is the most important carbon-carbon bond forming reactions were the import most important class and bonding reactions in the field of organic chemistry or maybe I should say organic synthesis
of case or we're just going to talk about over and over again over and over and over when
tugboat that that's what we want to talk about the someone start up by late Friday helping us establish a picture and enamel picture of the pie bond more various types of buy bonds and what I want to do is I want to contrasted these types of Pi systems the street every pie bonds and we're going to see all kinds of reactions were these acts potentially nuclear files we were going to see a lot of invited some sort of an electrified cargo can iron and I think about that editions that explains electrical like aromatic substitution in whole so many reactions at that explains what I want you to do what I want you to avoid doing this and it doesn't matter what the Electra Eliza could be a proton like an acid could be a couple can find could be aluminum plate that's not the most nucleophilic part and basic part but the molecule we've said this over and over when reacted calmly held I want you to use these and that's what I want you to use and unlike the same you might think think they give you the same thing all they gave me the same sort of resolution but this despite bond is not as nucleophilic is that those those long pairs and familial sees pairs and it if that were true for oxygen it's doubly true for any right that's the nucleophilic part than any that's the basic part of inning not the pipe so use the lone pairs of course was commenting on how long pairs on carbon so a double bond you're going to use the pipeline snow choice with that because you keep that in mind the stomach and other trajectory here the 1st of what will
and I wanted distinguish additions to Carbondale because we wanted to sell much detail about the correct correct trajectories tradition Kerviel's we said there was this thing called a birdie done its angle it honors the fact that pie star looks like this Price this sort of phasing picture that looks like this and famine nucleophile trying overlap with this empty piste orbital if you're a nucleophile adding this to some sort of pie stock and I'm going to arbitrarily phase my nucleophile have some empty orbital like this that's unhatched I want to minimize my interactions with these hatched lobes of stop at those destructive bonding interactions I wanted told myself around so I don't have any interactions
come with these opposite the phased orbitals and the only way to do that is to attack was 109 degrees angle the
brigade and its angle but things are totally different when we had a lecturer files to see see bonds so if you're an electrified while not adding the piste are it is for an electrified all its opposite this thing is that nuclear policy blunders the nuclear file and saw hydrolysis if I draw the sort of orbital picture all decompose this pie into our arms into into the the individual P orbitals now if I want to maximize the interaction of this pipe bond which is now the film orbital in the nuclear file and have some sort of fictitious empty orbital here now I do want to maximize the interactions between both of those lows the prediction is the 1 electoral files attacked Barnes they should approach from the middle you simultaneously will get bonding from both of these carbon atoms to both of those
carbon that you can't avoid that is close to you discovered and you're also going to be someone close to them and and both of those
interactions are going to lead to bonding combinations of cases a trajectory difference between adding Elektra files to pylons presenting nucleophile 5 or so 109 degrees angles here whereas here you approach in the middle of the double bonds that's the expectations OK so long let's for a brief moment back to an old idea what I wanna do is I want to contrasts to different types of elimination geometries for you and will take this sort of fictitious example here of glory have tended doesn't have to be a chloride leaving the believably doesn't matter could be proved needed water ready to leave but if you contrasted these 2 types of geometries for elimination of the choir group the 1
on the right hand side the 1 on the left hand side which 1 is better which 1 is going to eliminate chloride faster if I think about where
sigma star is located for this carbon going on over here I would expect this 1 over here on the left-hand side to be faster than this 1 over here on the right-hand side so I hope you already know the into eliminations were favored over certain type eliminations so what we're really saying isn't this has a lower energy trade missions state the transition state in order to eliminate here is lower in energy than this other transition state so this transition state is lower in energy to give you that but we're
also saying but even I could do in theory something like this think get to something that looks very similar Boggess identical what I'm really
actually saying is that if we think about the opposite reaction and I think about nuclear files adding the that transition stay I'm also saying that that transition state is lower in energy either the transition state lowered energy or it's not that means for both the forward and the backward reaction this transition state is lower in energy than the 1 where I attack like this and I want 1 attack with with some sort of a nuclear file on a piste star that lone pair that appears on the neighboring island doesn't appear into the nuclear file it appears on TV to the nuclear file it's the same transition state for pushing out a leading group or for adding and so here's the big point that I'm making right here's the take-home lesson from this incident and
whenever I have some sort of a double bond and I have a nucleophile that's poised nearby and to make this interesting all make this a
metal but to make this metal carbon bonds the nucleophile if the metal carbon bond is on top of this price system in attacking it from the top what that means is that this pipeline will be nucleophilic on the bottom face that's a that's a consequence of this scary electronic relationship that I showed you above if I nucleophile detecting pipe bombs from the top faced that nuclear fissile Felicity will be realized this is really just a resonant structure all that nuclear Felicity will be realized on the bottom face that's the important point and it's all related to this in
many mind thing that I should you approve was takes an example that Saturday that become useful in organic synthesis or any consequence and it's only going to
give you an example I'm going to try to draw out of it as best I can some sort of a cyclo hex e-mail system edge-on because I want to see both bases and that the top and bottom phase of the cycle Lexington and of course it doesn't make a difference being what is the topic the bottom unless I have some substituent there so just to help me keep it straight on a primeval group on the top face in this cycle exit sign of a reaction occurs like Intel Ehrlich arise from the same faces the medical or the opposite faces the methyl and of course Al-Qaeda Andre nucleophilic so suit this up and we put some nucleophilic bond here that small nucleophilic let's make that 10 there is a long nucleophilic bond you should not be
surprised after I went through this despicable over here about the fact that if I probably make that Bonda reacted with any kind of an electrified but
suppose I prove made bond course I can tell impregnating values protons make this deuterium to nullify prove make their bond my expectation should be that if this is donating from the top face and I'm not going to actually move those electrons but if Visteon cotton bond is really nucleophilic an Israeli Supreme love it if it's really donating into that that price system and suiting up the basis city nuclear Felicity the pylon it on the happening on the bottom face opposite this hydrogen bonds among the top place and that's exactly true when you look at duration of this exact substrate what you find is that the deuterium gets picked up on the bottom face amount is going to drive D instead of just the sort of isotopic symbol
some of those on the top on deuterium is on the bottom when you get this phenomenally stable beta
understand all all-cargo can with this long nucleophilic tin bond there and this acetate is floating around looking for something to attack energy right there that you now it's not an innocent to substitution but that acetate is going to attack that tenants and pop off and so the finals compound that you get out of this is that the deuterium is going to be on the opposite face of the methyl is this is really powerful useful stuff and we're going to see now is a zillion reactions of al-Sistani's analysis I lanes and Howell any metal you want where there's this facial selected the medals on 1 face electrify was on the opposite faces just keep that in mind but from there is another example of exactly so maybe you don't care about probe nation reactions who cares about that
prove nation isn't very interesting process I would agree with that it's extrapolate this a little bit principles we take analysis I Lane you had
some magical way to make this optically pure and doesn't have to be magic and now what you're really interested in is a canister CC bond formation and Soviet my electoral violence you taken apart side missed blocks to rein coordinated that taking into it required so that now that the Sox arenas very clear very electrical and very easy to attack so you see attack your expectation should be is that the Electra file should come in from the bottom face opposite the silicon that's true that's what you see here is intermediate that you get if you will of years this Koble cat iron
I love that Cobble cat that beta silicon silicon carbon bonds next door donating in the NTP will role in stabilizing and I just made a new CC bond on the bottom face that system it's the bottom face
a battle attacked the apartheid and opened it up and I'm not going to go through all the steps here to exchange but ultimately after you do the work up what you get all of is this new carbon-carbon bond on the bottom face opposite where the silicon was OK so keep that that feature in mind we have nucleophilic bonds next apply systems they're going to make those pies systems more nucleophilic than normal and there's a facial selectively to keep that in mind focus now come back and simple mechanisms that I kind of hope you already know but maybe not in the detail and I'm going to show you so at some point during the time of year for the 5th month in soft more organic chemistry started learning about a zillion reactions were you add electrified Ulster on allergens like B R 2 were sealed to Europe HCl missiles come back and look at those reactions that I hope you already know which include missile start off by I'm going to try to drown out the here the money during a 2 2 draw this Alpena John so we can clearly see on the balloting has 2 different faces associated with the sun and trying to envision Alpena Johnson others top facing a bottom face to that cancel fired bromine to this to yield the end up making the dive bromide all want to die bromide and we know that these reactions involved the ammonium ions what does ammonium the promoting a
means of bromine that to bonds this 1 just happens to be a three-member Iringa the ammonium ion always if you just had to bonds to bromine it would be a morning line and in the spring monument just happens to be
strained in cycling so these reactions go through this cycle of ammonium ion the strain site click around bemoaning alliance under-strength ammonium here 2 monster bromine so how do we push heroes for this the way you push heroes for this on is that we have to show that it's the pie bond that's attacking this bond it's a weak bond it's easy to attack it's got a low-lying Sigma star that makes it easy to attack the challenges that it as you take these electrons away from 1 of these 2 carbon atoms you're going to leave the couple cat eyes and a couple can is not going to be happy if you start taking away electrons from say this carbon well isn't there alone hair that's right here In fact 3 lone pairs the poised and ready to start adding that Koble Caroline as we develop it so it shouldn't be surprising to you that as you're attacking this you could come back in with the lone pairs and make a 2nd bomb and so that's this is the traditional way that we depict please please br ammonium ions and so if we have some sort of a bromide here that's left over the 2nd part of this mechanism is to come back in an attack on either side that would give you 1 intermarriage the the other Fietek missile get wanting to at the other side of the other 99 as long as those are the sort the same but the bottom line is that brominated should give you an AT an overall and the addition of bronze where the 2 bromine atoms end up getting an added from the opposite face what about rest of the way in which the so the 2 bromide an advantage which other and of course if the molecule can spin around that central bond and the students clear only when you draw like that you think you can see the interrelationship is a disturbing piece of information that is actually disturbing so this is not the correct mechanism in reality but this is how I would like you to draw I'd like you to draw up the way you've been drawing it since 1 but in case anybody ever asks you cheated anybody ever teach you the correct mechanism for rumination on at least you can say you've seen it somewhere it turns out that in reality bromine forms of high complex with all things before there's any Scotland bromine bond formation it turns out there's an initial complexation and probably this is we don't have good Lewis structures to depict
things we have to draw things like data bonds sometimes people drug use -dash bonds to get this Pike complex sometimes still on policy also known as a k a the charge transfer complex this is so what is this
charge transfer complex a charge transfer complex basically means that the pie bond is donating into to this bromine bromine bond and it just sits there with this pie Bondo meeting and addressing the star orbital liberally and there's no there's no dissociation of bromide initially initially they just sit here like this and then this bromide gets pushed out to the Supreme Coordination and we're not going to draw that we're going to continue drawing this is exactly the way the EU grumble for someday you're going to run into some reaction you can't explain I hope you'll remember
this picture of ruminations so keep drawing halogen nation reactions with C 2 and B R 2 in the same way that you don't just use the zeros here to
push this don't draw it 2 steps on but if you ever need to you can fall back on the picture it is further rumination on her coronation double bonds of Soviet literary rates of rumination on allow kids in methanol it's going to talk about how the structure of the Al-Qaeda influences the reactivity and toward electrified also something joyous series about Keane's here and All-Star with ethylene gas pathetically on reactive Oliphant awful awful and low reactivity Oliphant there's no substituent on I putting in a single alkyl group unmarried 100 fold rate acceleration just by having a simple kill and if you want some
way I'm not going to go back through explain this to you but it's in on it's exactly the same as that carbon so well it's the same type of ideas that carbon silicon the Covington bond these
bonds these these Proton common bonds are donating enterprise .period they're still being up the nuclear Felicity that private so that's of the effect of having these bonds nearby knew little of they soon about this piled on nuclear Felicity and you don't have those bonds on ethylene cost when I look at it and eternal offended a CC double-bond end an alkyl chain I'm thinking that looks on reactive to me the visitors relative rates of rumination how fast these pipe bombs attacked bromine this terminal looks on reactive to me when I think of reacted outing they think of internal things that have to alkyl substituent son that's a more typical of the type of substrate feel useful and and this is
another factor of 10 factor 20 actually closer to effective 20 In reactivity having to alkyl groups is even more reactive dismantling the double bond to the middle of beauty it makes it that much more
reactive and if I rearrange my bewteen still for carbon atoms in the right way Nigerian higher reactivity and you can have all kinds of explanations for this the way to think about this this arrangement so these both have 4 carbons and look at the reactivity here Is it here if I think about what this age common bond is doing this kind of soaking up the reactivity over here and there's a ch bond over 3 of them on the siege on the where the setting up the other carbon reactivity but you'll be higher reactivity if both of these substituent are suiting up the same carbon but if you want to draw some kind of a resident structural help you see that both of these are cooperating accelerating and gleeful city in this country have been missing since this higher rate of additions and then the fastest of all these would be a try substituted often is an important point here is that not all of they're not equally reactive if you got some complex substrate and you want to do a selective approximation of a of a internal offenders eternal thing you will probably be able to get a high yield that so different levels of nuclear Felicity when you add a lecturer files orphans depending on the substitutes that renewal of the common killers couldn't go and talk about the intermediates involved here so this idea of brominated double bond or found that 1 of of the more people who work of for
the Sony Johnson's a reaction like this finally I know it's not like this with this cycling br ammonium business I like and I just make up a free cargo
Caroline like that I don't know whether it's going to this sacred Ramon mind is all-weather instantly attacking having a free of closing chapter on this whole show you how you check what you do is you look at the percentage of it really is going through this this kind of cycle were ammonium ion the 2 bromine will always add ante to each other because the leading group was on the opposite face of for the Nuclear files attacking someone to give you a series of all events and we can see how the substituent did affect whether you're going to the
site could Ramon EMI so in simple internal often you get 100 per cent in the product out of this unity edition of the of the 2 bromides I tell you that
100 per cent of that was going to the site with br ammonium mind but if we put a cargo can find stabilizing group we can tip the balance right if we stabilize this and now we can start to season Koble Kanye information some of it goes to the site would bemoan and some of the goes the free carbofuran remember these are the 2 choices by the longer coming back in attacking the noncallable can iron as the as the bromine answers for the double 1 simply attacking the bromine and leading a free ,comma and so when we have them over appears 1 of our substituent we see only 83 per cent in the addition another awards some of this is going to the free Koble can I like this and if we really substitute if we added a 2nd Substitute to really help stabilize this cargo Caroline at that center now we see only 68 per cent in 2 editions of 60 per cent of it for a lease for a
significant fraction of this is still going to the sacred br bemoaning mind even know we generate in theory of very stabilize Koble can were still getting a very significant amount of the cycle of ammonium ion formation so cycle
bemoaning mind formation is the rule I'm even when you can form stabilize cobbled cards the gunmen who wouldn't stop right there and will come back and say I feel like I'm going to say almost all the same things when we had HBR HCl and acids to double bonds
Single electron transfer
Chemische Reaktion
Quelle <Hydrologie>
Chemische Bindung
Elektron <Legierung>
Fülle <Speise>
Bukett <Wein>
Advanced glycosylation end products
Nachwachsender Rohstoff
Elektrolytische Dissoziation
Organischer Halbleiter
Funktionelle Gruppe
Weibliche Tote
Aktives Zentrum
Setzen <Verfahrenstechnik>
Gangart <Erzlagerstätte>
Hope <Diamant>
Initiator <Chemie>
Spezies <Chemie>
Substrat <Chemie>
Organischer Halbleiter
Heteroatomare Verbindungen
Chemische Forschung
Immunglobulin D
Organischer Stoff
Chemische Forschung
Chemische Verbindungen
Konkrement <Innere Medizin>
Chemische Struktur
Systemische Therapie <Pharmakologie>
Aktivität <Konzentration>
Einsames Elektronenpaar
Email <Beschichtung>
Orphan Drug
Eliminierungsreaktion <alpha->
Chemische Eigenschaft
Chemische Struktur
Kettenlänge <Makromolekül>
Chemischer Prozess


Formale Metadaten

Titel Lec 14. Alkali Organometallics (Pt. III) & Lec 15
Serientitel Chem 201: Organic Reaction Mechanisms I
Teil 21
Anzahl der Teile 26
Autor Vranken, David Van
Lizenz CC-Namensnennung - Weitergabe unter gleichen Bedingungen 3.0 Unported:
Sie dürfen das Werk bzw. den Inhalt zu jedem legalen und nicht-kommerziellen 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 und das Werk bzw. diesen Inhalt auch in veränderter Form nur unter den Bedingungen dieser Lizenz weitergeben.
DOI 10.5446/19212
Herausgeber University of California Irvine (UCI)
Erscheinungsjahr 2012
Sprache Englisch

Inhaltliche Metadaten

Fachgebiet Chemie
Abstract UCI Chem 201 Organic Reaction Mechanisms I (Fall 2012) Lec 14 and Lec 15. Organic Reaction Mechanism -- Alkali Organometallics (Part 3) & Addition of E+ to C=C Instructor: David Van Vranken, Ph.D. Description: Advanced treatment of basic mechanistic principles of modern organic chemistry. Topics include molecular orbital theory, orbital symmetry control of organic reactions, aromaticity, carbonium ion chemistry, free radical chemistry, the chemistry of carbenes and carbanions, photochemistry, electrophilic substitutions, aromatic chemistry.

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