Lecture 19: Stereochemistry of Radical Reactions & Free Radical Oxidation

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Video in TIB AV-Portal: Lecture 19: Stereochemistry of Radical Reactions & Free Radical Oxidation

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Lecture 19: Stereochemistry of Radical Reactions & Free Radical Oxidation
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This is the second quarter of 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: 00:57 - Radical Substitution of Benzylic and Allylic Hydrogens 05:05 - Stereochemistry of Radical Reactions 13:10 - Radical Addition of HBr to an Alkene 24:57 - Radical Initiators 26:12 - The Peroxide Effect 30:06 - Autooxidation 37:46 - Preventing Autooxidation: Addition of Antioxidants (Free-Radical Scavengers) 39:20 - Conjugation
Hydrogen Computer animation By-product Bromine Chemical reaction Wursthülle Radical (chemistry)
Carbonate platform Sense District Ionenbindung Biosynthesis Reaction mechanism Benzoic acid Radical (chemistry) Operon Ocean current Radical (chemistry) Wursthülle Lightning Chlorine Chemistry Ammonium Electron Colourant Common land Active site Benzene Mixture Process (computing) Oxide Substituent Setzen <Verfahrenstechnik> Molecularity Peroxide Carbon (fiber) Katalase Superoxide Hybridisierung <Chemie> River source Chemical reaction Electronic cigarette Gap junction Water Hydrogen Stream gauge Computer animation Initiation (chemistry) By-product Covalent bond Chemical structure Bromine Medical history Thermoforming
Ionenbindung Chain (unit) Weakness Reaction mechanism Growth medium Radical (chemistry) Molecule Electron Atom Process (computing) Setzen <Verfahrenstechnik> Octane rating Walking Hydrogen bond Carbon (fiber) Katalase Chemical reaction Oxygen Combine harvester Hydrogen Computer animation Initiation (chemistry) Wave propagation Covalent bond Bromine Thermoforming Dipolar bond
Übergangszustand Ionenbindung Reaction mechanism Rock (geology) Peroxide Walking Hydrochloric acid Radical (chemistry) Chemical reaction Wursthülle Electronic cigarette Stream gauge Computer animation Wave propagation Natural competence Process (computing)
Stop codon Resonance (chemistry) Lebensmittelhygiene Radical (chemistry) Food Reactivity (chemistry) Molecule Linoleic acid Colourant Butylated hydroxytoluene Explosion Conjugated system Synthetic rubber Oxide Metal Peroxide Gas Malerfarbe Carbon (fiber) Topicity Fat Oxygen Water Hydrogen Computer animation Resin Covalent bond Chemical compound Chemical structure Thermoforming Stuffing Biomolecular structure
Flüchtigkeit Resonance (chemistry) Carbon (fiber) Electronegativity Radical (chemistry) Soil conservation Electronic cigarette Chemistry Oxygen Paste (rheology) Molecule Systemic therapy Computer animation Electron Acetone Chemical structure Conjugated system Periodate Pipette
Chemical property Density Carbon (fiber) Hybridisierung <Chemie> Atomic number CHARGE syndrome Wine tasting descriptors Molecule Computer animation Electron Tidal race Molecular geometry Controller (control theory) Covalent bond Common land Orange juice Stratotyp Chemical structure Benzene Conjugated system Body weight Pipette
Ring strain Computer animation Tiermodell Covalent bond River source
Computer animation Ageing Covalent bond Chemical compound Verwitterung Conjugated system Stuffing
Computer animation Electronic cigarette
Bulgaria this chapter of 15 seems today and then we will start Chapter 16 everybody knows there will not be any Chapter 16 on right but we will be covering through Chapter 15 I will not be making mid-term deliberately accumulates in the final will be delivered between militants but of course when you're doing some business problems you need in all reactions that we work very hard questions before we get started anybody or something similar .period last I'm talking about radical substitution of events elegant Alec from hydrogen so Galileo and then sell it rumination there and yearbook uses to allow during agents for this they use bromine and lights for he's it's still running in light of the Roman letter and what we learned is that we certainly learned in Chapter 10 that there is a competing reaction for this where we do maker once and I will compound that's very fast reaction and competing and that's what we're going to learn is that in some cases it would instructed each team would be actually brought the aromatic ring and so we want we want to avoid these products from the side products forming this kind of thing so although the book is using this and a lot of different places I want you to use a different regions and that is and were almost starts the good news for that is
that we can never abbreviation Indiana that is India's not NBC OK so envious and Bromo sentiment is the reagent so rarely use and the and we use of peroxide so peroxide and is this is an initiator of life or at the end peroxide so the NBS is ah are a source of bromine and peroxide is a radical initiator and this is the region that I want you to use instead for Allergan pencil implementation so here are products going to be there only we're going to get any side products no side from the site product that we would get here would be 1 with the UN inside edition of bromine to the double bond which is not a radical program cut process alright and likewise when we have been selected for hydrogen is that we can remove but we will only get the pencil acquired so you'll appreciate the 2nd 1 more when we get into Chapter 18 been itself is not an ad from without a catalyst but other other rings have benzene rings with different substituent will add bromine to the ring and so we don't want these competing reactions to take place so the authorities and the US instead so on test use NBS R O O R and heat or light light or heat 4 hello and then sold from a nation are now good news is only said last time we are not going to know that you don't need to know the mechanism for this reaction it's a complicated mechanism and has set official Garrett and enhance double-headed heroes so it gets a little involved in it's not something I want you to take your time for us so we're skipping the OK so no no mechanism for this reaction Our right on its again brief composted talk about the stereo chemistry and we're going to talk about the 3rd reaction that you need to know from this chapter so the 1st reaction bromine and your lights to taken out Keenan make it into and out of the reared in a form the most stable of radical also usually that's going to lead to the more substituted alkyl he lied and broke means much better than chlorine for selected in the 2nd reaction is elegant benzoate rumination were released India's peroxide and utilized but that's not the reaction number 2 you don't need another mechanism for reaction virtue related to a 3rd reaction from this chapter but 1st let's talk about history has revived as a player and as the June highrises Rossini mixtures are obtained in reactions for mysterious and that makes sense because these are as radical as S P 2 hybridize so we have a plane we have a key or on the top and the bottom with a single electron and some things in common and tackle toppings things continue community attack about we are going to get people so we won't be able to make sure the remember that right so here we have found a Cairo reagents a car reagents and we're going to form a secondary radicals we can go either here or here yeah platform a secondary radicals by loss of a secondary hydrogen we will not be a little more radical on-time arrival here and so then let's look at our intermediate it's a bit the radical intermediate we know that there is a S P 2 harbor last so carbon did carbon from the radical she and the 1st Adams are all in the same plane so let's Mercosur so so this carbon carbon that hydrogen and that carbon are all in the same plane and let's go around and didn't do that and also these guys are all in the same place we have our hybridized curable change the color so we can see it probably did not allow foreign on hybrids curable that contains a single electron that's the structure of the radicals and the roaming Kincannon with this radical is going to grab bromine from molecular bromine from of the ABI are OK and if it attacks at the top of the case In there's the productivity gap His roaming coming in from the top member once that bromine of bonds to the carbon it's not fuel not playing any longer and if it comes in from the bottom of the bromine consent from the bottom and this is the 1st time we've uses this word but is it's called the face bottom-placed top face and if it comes in from the and then this is what the product looks like and so
we we started with a current regions and there's no Cairo influence then that means that if we have a stereo center in our product and we did so there's a stereo center right there that that the mixture must be received so product tests during center therefore must be restored so you have your thinking you're going to get away with thinking about Syria chemistry and we're not done yet OK so deftly steered constantly have to worry about here so this is a Rossini mixture if we want to get a single insurer we have to have some Kiraly influence and that's what we saw with the circles of oxidation there was a catalysts that formed in that reaction so if we get a single image but unless we have that we don't have that we were going to get worse in next so in addition loss of optical Carretero occurs substitution occurs at a car center so just like in Chapter 7 we didn't want to use S and wonder if we did if we didn't want rationalization same thing here so if we start with something that's optically pure we have this ,comma coveralls center here optically pure I generally speaking making things the optically pure is a lot more difficult and if we tried to do this reaction with optically pure once we do that but some draw intermediate we have again a planar intermediate just like at the Essen 1 reaction occur cat and this is also playing an intermediate the only difference here is we have a single electron and hybridized to your and so on the intermediate is a car so a car intermediates it does not matter that we started off as something that was optically pure we get Rossin stations so we get lost said optical character and so when we do this reaction we're going to get you products From in a command from the top it's going to come in from the bar so what struck of them not just abbreviated the benzene ring with pH so here is the product of the Roman comes in from the top here is the product of bromine consent from the bottom so here's the bromine coming in from the bottom that's so something to keep in mind that when we're doing radical reactions we do I want to avoid a strike action if we have a snow Carroll said that we're trying to do substitution alright questions on stereo chemistry and yes this is not like that yes or not making of ammonium 1 euros although we were talking about ammonium ion attacking from the bottom that same terminology the I just haven't used it before a Western losing now seem like a good idea place the start came right recently received 3 reactions that you will need synthesis and this is number 3 radical addition are to announce Keno we know what happens when we had a we are him what type of player additions that work on it ,comma intimate chronicle the contrast to the growing those animals substituted side so this we already know that stronger product here somewhere ,comma so this of course is Chapter 10 now if you do the same thing you take the same Keenan you take HBR are and you added as a radical initiator superoxide radical initiators and when I give this reaction on the radio and in Internet the end typically you need to know that he alive sometimes you don't but I will usually just just to make it easier for you if I'm if I'm wanting to do a radical reaction and I'm having to predict the product I always write each additional it's so that you'll know it's radical but you can certainly also do this with some heat but I will always use each new when I want you to predict a radical product and so this is the only the only difference hearing is is this radical initiator and what they want and what you end up getting a in Timor ,comma competition so on entire work on with that's really solely on the hand that sometimes we wanted terror ,comma competition so we have no sure reactions that do and Timor ,comma called this 1 would us with the other hide operation right both of those too intimate chronicle of hide erasing gives you Inter-American accommodation of water at this station you ,comma competition at HBO so was only to you that's all we're going to learn all year you will need those over and over again since it's so surreal it's really enforce the reaction so this is on mechanism types to that might be on the tip the tests
coming up so we're going to have a radical mechanism on the staff well so that have other mechanisms that are not radicals but that you have really a choice of 2 in this chapter reaction in which you were not learning the mechanism so this 1 is actually understood initiation same idea when we initiated the breakaway bond and weak bond we saw a chart with weak bonds in the notes for this chapter and weak bond is an oxygen oxygen bars so will start where Our retreat radical initiator and and that the name of this tells you what's the very 1st arrived at the wrong far we fix that yeah you don't want to do that don't do what I just did OK this is going to be 2 steps of initiations so what are you doing the initiation you break apart the weak bonding the radical initiator that's going to be the very 1st steps such as it's an easy way to remember that so rating is politically 1 electron goes to oxygen and 1 electron goes to the other oxygen so we're breaking out of bondage and we're going to form to borrow money are 0 or 0 . 2 and Copsey radicals then the autopsy radical and I'm missing women appears here so let's go ahead and those there were going to do is Morgana actually make coordinator bromine radical here so there on aura of radical is going to grab a hydrogen from HP Obregon a break the siege on bond politically when electrons in a combined time in media with that rapid the unpaired electron from oxygen and then we're going to have found former New oxygen hydrogen bond and this is bromine radical that's the 1 we're going to use for this reaction that's the 1 you're going to start with and the propagation and people keep reforming OK so that's initiation when we added free-radical initiators usually going to be sometimes it's even more than 2 steps writing just break the HBO gone by the way why don't we just break this 1 and have to address they we not yet what exactly and Wednesday to instead it's very appropriate that it's gonna put the pipe so that those 2 reasons yet exactly correct so that this is going to do is the 2nd 2nd type of process we talked about at the very beginning of this chapter the first one was obstructing an atom from another molecule in this 1 is adding into the double bonds so here's our bromine radical that we just made and it's add into the double bond so we're going to break the double bond politically when electrostatic combined with the bromine just like that we want a form the most stable radicals so that's why I'm breaking it that way so I want the radical legal on the secondary carbon not the primary and what you want a check for is that all of the Europe propagation stacks we start with 1 radical and we ended 1 at radical after each step if you start with something that's not a radical when you make to radicals well then it's not a propagation its initiation if you start with 2 radicalism you end up with no radical that's a that's termination so that's what that looks like and then I and this is the book's Oregon and to redraw the now on our job here is to regenerate our premier radical that we started with so the bromine radical that we use in the propagation isn't is really it's starting with the 1 that came from the initiator but we'll continue to fund the wrong in that way we continue from the bromine ions in the way that we got to show you right so we're going to come and grab hydrogen from HBO there's a hydrogen right there we just for many bond C H 2 R and regenerate our problems I always wanna that's what we started off well there it is right there we're agenda is at Annex 1 link in the chain and cycles through 1 out 1 molecule at a time of just like that very surprisingly fast many of these reactions that termination radicals destroyed by recombining could take any to radical we have here recombined them in the in the termination St so I village on the test I will ask 1 Termination saving the good everyone what you can have your cat termination reaction combined to close together can do that RE questions about the
mechanism anybody if from separately as the the the Jakarta when the team that's pointed to the greater number of marriages to form a secondary radical rather than to form the primary radical White of so why knowing you are doing weird said while the let's right would still the missing here why no secondary product and if we reform secondary products if reform this radical 1 this radical because it's not as stable as a secondary radicals there's a big difference and so on because
the transition state leading to the secondary radicals it is lowering energy the transition state leading to the primary radical I mean with the transition state looks like we use him as possible at the transition state is gonna look like the eve of the religion of the product whatever its closest energy to and since this is an end-of-term reaction is gonna look closest to the product which is a radical of anything that stabilizes the product radicals can also stabilize the transition state soon and killed peroxides Indian is a radical initiators of about a different ones he created because increase radicals were approximately the reaction would not occur recognition is Army commands it readily undergo also so there is only getting just a little bit more reactions here this is a 44 k counts for you might recognize that region is 1 of the regions that is used in the sharpest station the case of at a guarantee there's some sort of a radical process during the reaction widened show you the mechanism actually radicals are reacting in a lot of those reactions from Chapter 12 but the way too complicated for this class so that's 44 what do you do demonize these numbers no I'm not big on numbers just just I was only recognizes the got the 2 had multiple pairs right next to each other and that's going to make for a weak bond and is there sound pennzoil peroxide 32 accounts for more and this is 8 AID and don't have the it's very low also don't I died I forgot to look at the number for that aso besides international it's another common initiated so we call this the peroxide effect if we if we don't act rocks the polar mechanism we get more ,comma competition if we peroxide we get in Timor ,comma competition the radical process not policy we call this on the product side effect and this effect occurs only with state-of-the-art knowledge HI wife and the reason is that if you calculates and the be change for each reactions of radical addition of HBO are the 1st propagation step is XO 2nd propagation state please step as acts 1st propagation stepper ACL is out like so thoroughly 2nd propagation status and and for each and the 1st step an exaltation 2nd step it turns out that for the 1st obligations that the 2nd propagation stepped in both steps are not Axel political reaction doesn't go and you get a polar mechanism to shed so only when all of the propagation status Our an excellent 3rd Kim propagation compete with termination so notice in termination reaction were taking to radicalism combining them to make a bond is at Exeter at end of we just making the 1 operating by excellent so we have this act so thoroughly termination step which is competing for propagation but have we had any of these Dexter and ultimately doesn't go so HBO is the only 1 interviews for this reaction no cases 8 a giant hydrochloric acid applied Arroyo against only ionic petitioner occurs To the American even if you have peroxide in parts of suspicious said they're not not not react even if you are Horowitz in
strong line right here midterms steerage serial up through here the last part of this chapter is a little bit topical and letting go quickly through the testing rights intermediate stops right there OK I oxidation of still oxidation when it went organic compounds are exposed to air react slowly with oxygen peroxides this is known oxidation it's responsible for the slow deterioration of air and food rubber and paints some some sort something Johnston to defeated more than others rent is a big 1 who was a big 1 that's all caused by auto oxidation if you can't you keep outside for for a long time and it's all crackling right you know these things like that these things break apart Benson ,comma very easily autopsies composite form especially stable radicals so that's something we want to look for so you can imagine and live in the presence of oxygen and this guy right here conformance there seems stable radical right tertiary Denzil radical could be better right so that's going to be especially prone to arm oxidation In machete would Idaho outside looks like this a very reactive and potentially explosive so turn this nice benign compound into a peroxide and proxies of course are going to be especially reactive compounds with hydrogen atoms on a carbon adjacent to an oxygen is also prone to oxidation In so you've used I die the the last rites that you have to be really careful with Dieter Lisa you have to use it up pretty quickly and and if you don't use it up pretty quickly then you have to go will form peroxides a peroxide so this is dire I don't outside extremely explosive of there's going explosions without either that's been left out too long under the data in the lab will use the finding in a metal came with a very especially on hydrous sees the you'll find it in and out here with a very small opening in the top Rose like that so that not very much air gets in there because we don't want this to happen about when this has formed and people had not been careful there's been a very serious explosions I want particularly heard about where it took and moved an entire wall over 6 feet and that's what the explosion itself and things like that and the other thing that's very prone to oxidation are polyunsaturated fats polyunsaturated fats and and so this is well linoleic acid better be careful with these guys this is linoleic acid I don't said but also not very very healthy for years so let's let's look about it and think what's happening here so we've got a little late gasses Leach ,comma hydrogen in that molecule is going to be easily Morocco will agree that most of the most stable radical you could form from that molecule wearing the emitted carbon numbers starting from program as to the please this guy right here right L at 1 side outlook on the other right doubly elderly very different oxidation right there very very prone to oxidation and so on but that doesn't look like a product that we have a major show you very quickly how you formed the linoleic acid Hyder peroxide so what you do this do not need to memorize this this is just for your own betterment as a human being in your own safety because you're going to be careful about this stuff finding polyunsaturated fats are really good for you but he needed to make sure that you don't keep them too long so that's where going Oregon and abstract that hydrogen that's what we would get and they are likely remind this is this when you and how will the radical you have to draw the resident structure and this is not just in this last part of this chapter this is when you're doing hourly from nation's make sure you draw the resin structure and you will get products from both present structures so we know that Alec radicals are resident stabilize reducing that at the beginning of chapter 16 also and there was something in lab last week for a did that will do that again this week and so went on to I'm just going to go like this and I'm just going to do resonance stabilization I didn't show you the pushing for this but we did talk about this at the very beginning of this chapter and I know what that dies it is not the issue this radical what's good about that we just did what does that mean that radical more stable so we're actually in this restive structural making it ripe for stabilizing Dad double bond amendable water conjugated remember conjugation and stability wouldn't talk about that morning Chapter 16 which would start remaining here but and this is now conjugated so it's not only Allah but it's conjugated use double bonds are conjugated so this is now Ltd plus conjugated and so that is going to insert what's going to happen is that Saddam the oxygen in the air In oxygen in the air is a dire radical at Bowman Gray here just like
that right and then we get this and that's going to grab a hydrogen from another molecule the when change the color student will better skin that and hydrogen from another molecule of our H which is another molecule of the linoleic acid and so on was that's 1 of the reasons why I manufacturers unlike to add saturated fats or hydrogenated fats partially hydrogenated fats and hydrogenated fats and because if you do that you get rid of this guy right here there more shelf-stable young and to keep them refrigerated or other costs that the polyunsaturated fats are definitely much better for you and so 1 of the things that I think manufacturers do is In oxidants so they need recognize some of these BHT BHA are added and and the reason that we use these days that this 1 for example and forms a really stable radicals so it removes the radicals that start to form To keep the food safety and this particular 1 is very stable as it's so hindered if we give we actually drew out all those church future she would see this is a unhindered the Nazi radical so it tracks and the radicals the form and that's why we have those on on intact OK questions on Chapter 15 anybody yeah we just start to save this and go ahead so won't
1st this 1 here Taliban movement
not involved that's the part of the test yes if you if you if you're making a resident structures in the earlier part of the chapter its tested on you would want to draw residents here yet are right that student chapter 16 who wears Chapter 16 so scary for a minute there OK now the 1st the 1st Chapter
16 and say I will I will know that nobody talked about that so of some of the 1st part of this chapter especially if you had my past before I talk about condemnation this is actually the 1st place that's talks about ,comma conservation and so there's actually some chapters in the end some problems in the end of this chapter that had been destroyed resident structures like we did back in Chapter 1 pesos seems in some ways a little late to do it that's why introduce it a little bit earlier so this is all about conjugation residents and dying it's conjugation occurs whenever appearance can overlap on 3 or more adjacent Adams OK so we say that we know that all that's too we know conjugation makes things more stable but lot and that's because there's resonance stabilization so although this is a minor resident structure we are and actually moving electrons around to help stabilize this molecules so 1 and gets the negative charging 1 and gets the positive charge we ran across conjugated carbon meals when we did the IRA chapter and so that would look something like this we can move electrons this way on top of oxygen were moving on to oxygen were moving in that direction because oxygen for election negative in the carbon it's at the other end so that's where we're doing way and this is going to be important when we get into that 51 C and talk about carbon chemistry we also know about I will occur Catalans there a resonant stabilized but today so there's a resident stables alone ,comma Catherine we also know that will radicals wasn't just mentioned also resonance stabilized we're looking Arab pushing but that's exactly what you would get so you immediately on the lookout for these need to be on the lookout for I will occur cannons Ehrlich radicals and just remember that you need to draw the structure and and Alex program lines also although the removal of electrons in a different direction here are right so when it turns out that these conjugated systems are more stable than on conjugate we talked about already when periods overlap electron density the pipe bombs is spread over a larger volume this lowers the energy and stabilizes the bicycle so if you look at what this 1 looks like these to resident structures here if we had to draw all the furor but also this is what they look like In order for this volatility Continental's pure all have to be adjacent to each other parallel to each other if they're not parallel to each other than they can overlap
properties and this is what it would look like so they're all straight up and down parallel you till 1 like this you're not going to get conjugation and we we can say the same thing for all of these thoughts jumped over to this last 1 here and that's I change things a little bit where the weight learn things that Strobel hybrid for this last 1 where at Anderson also that in there yes OK hybrid rice and dried fruits it turns out that this is what it looks like we have overlapped all Waycross we're personal negative charge on the left Furcal negative charge on the rights that would be our hybrid Eriksson now there are going to tell you now and tell you that we lied to you in Chapter 1 a little better control told the little falsehoods chapter on are excellent so let's look at this take the orange Chapter 1 of the hybridization discarded when st threat but now look at that present structure right there what's the hybridization occurring now and in the present structure as the 2 and I'm so so it's not that that's not as free as the 2 OK so all the atoms across here as the 2 hybrids we all have to be a speed to hybridize in order for the zone electrons overlap and they all have to be parallel to each other in order for those electrons to overlap so this is going to look like this all overlap all away
across just like that if this if it's something was going on in this molecule and this common criteria on what's going to happen is if this is going to be coming as the 2 and this was not in a position if this was a position where is curable was not parallel with those in there wouldn't be it would be conjugate have to be parallel to the country are excellent the urinals overlap the density to the pipe is spread over a larger volume to a deal localize nonbonded electrons or electrons in was must be pure was that can overlap and that means that they're going to have to beat parallel this also means that the hybridization of anatomy is different than would have been predicted using the rules outlined in Chapter 1 has just demonstrated conjugate systems must be clear to overlap of Urals Oryx and here we have and this is benzene and we have 3 different drawings of benzene here this is the the orbitals notice they're all parallel to each other so we don't overlap on the spot we get overlap on the bottom it looks like this we should definitely all of those market that's all there was a double bonds there are conjugated and so the ring is plainer this allows for continuous overlap of adjacent urinals I can write it said so now if we make this to carbons larger so this is a six-member bring this isn't a member bring it seems like this would be the same as that right but the problem is when you get to these larger rings the bond angles change and this molecule here is not between and so what that means is that of these double bonds are not conjugated in this race there's no conjugation with double bonds these are all pondered this is not an that's because the P or bowls uncannily parallel to each other so we've drawn into alone so here's on the bottom here that would be there is a double bond there so there's overlap here and then we moved over to this double bond so that would be their notices perpendicular there's no sideways overlap those someone's were not conjugates of each double bond is what we call isolated so it is adopted term shape term shaped drain To minimize range therefore the double ones conjugated so we would actually call them on isolated double bonds
wounded in the head and killed a girl and the will not serve conjugated items for conjugated therefore double bonds are not 100 now I can't think current difficult to picture picturing strain here on I have these Adams I have and likely models in my office when you walk the combined take a look at them and identified in and remember if I remember only reminds me or bring them on Monday we have
to warn excellence talk about relative
stability is conjugated died little very soon we would call the stuff these 2 double bonds they're not conjugated so we would call them isolated these double are conjugated reverie alternate double single double single for conjugation user conjugated we know it's more stable weather conjugated because the residents but how much more stable so 1 of the ways we can figure this out as we can hydrogenated with the catalyst in endowment both go to the same compound so just like we did without teams if people don't have the same compounds of the both the products of the same stability demanded that allows us to estimate is we have dealt at age not I'm for the isolated is minus 61 the Council from all for the
conjugated this minds 54 and so what that means is that we have increasing energy going this way this is the energy of the art kind an end to the isolated is here releases 61 K Kallstrom all the conjugated only relay 54 so that means it has to start off at a lower energy here's 54 K Kallstrom so it's more energy than the isolated dying because it releases less energy 1 on hydrogenated will stop there will continue this on 1