Lecture 18: Radical Reactions

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Video in TIB AV-Portal: Lecture 18: Radical Reactions

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Lecture 18: Radical Reactions
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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: 01:30 - General Features of Radical Reactions 01:54 - Reaction of a Radical X with a C-H Bond 03:47 - Reaction of a Radical X with a C=C Bond 04:58 - Radical Mechanisms 06:40 - Halogenation of Alkanes 09:16 - Mechanism 1 27:05 - Mechanism 2 31:24 - Selectivity and Stability 43:52 - Radical Substitution of Benzylic and Allylic Hydrogens
Area Biosynthesis Chemical structure Chemical reaction Radical (chemistry) Electronic cigarette
Reactivity (chemistry) Molecule Computer animation Electron Radical (chemistry) Hydrogen bond Carbon (fiber) Chemical bond Spaltfläche Chemical reaction Radical (chemistry) Pipette
Setzen <Verfahrenstechnik> Compliance (medicine) Hydrogen Combine harvester Computer animation Electron Carbon (fiber) Chemical bond Radical (chemistry) Process (computing)
Reactivity (chemistry) Setzen <Verfahrenstechnik> Molecule Chain (unit) Computer animation Initiation (chemistry) Wave propagation Walking Chemical reaction Radical (chemistry) Process (computing)
Haloalkane Peroxide Radical (chemistry) Chemical reaction Chlorine Reactivity (chemistry) Molecule Computer animation Initiation (chemistry) Halogenation Functional group Human body temperature Mixture
Ionenbindung Chain (unit) Weakness Radical (chemistry) Chloride Radical (chemistry) Chlorine Molecule Electron Halogenation Methanisierung Human body temperature Process (computing) Setzen <Verfahrenstechnik> Dye Elektrolytische Dissoziation Peroxide Hydrogen bond Walking Carbon (fiber) Chemical bond Chemical reaction River source Hydrogen Computer animation Initiation (chemistry) Wave propagation Penning trap Thermoforming
Metal Chain (unit) Left-wing politics Walking Hydrochloric acid Chloride Chemical bond Radical (chemistry) Chlorine Molecule Combine harvester Hydrogen Computer animation Initiation (chemistry) Electron Metabolic pathway Wave propagation Mineral Stuffing
Setzen <Verfahrenstechnik> Chloroform Gravel Walking Chloride Carbon (fiber) Protonation Radical (chemistry) Chemical reaction Chlorine Methylchlorid Molecule Hydrogen Computer animation Methanisierung Wave propagation Active site Thermoforming
Bromide Concentrate Haloalkane Chemical reaction Propionaldehyd Chlorine Methylchlorid Organochloride Computer animation Methanisierung Functional group Halogenation By-product Chemical compound Active site Periodate
Rekombinante DNS Molecularity Computer animation Initiation (chemistry) Halogenation Wave propagation Chemical bond Storage tank Radical (chemistry) Thermoforming Biomolecular structure Butyraldehyde
Sunscreen Carbon (fiber) Radical (chemistry) Chlorine Food additive Origin of replication Hydrogen Cell division Computer animation Halogenation Thermoforming Biomolecular structure Stereoselectivity
Übergangszustand Activation energy Radical (chemistry) Chlorine Atomic number Whisky Origin of replication Molecule Halogenation Polymorphism (biology) Elimination reaction Periodate Area Octane rating Walking Chemical reaction Wine tasting descriptors Electronic cigarette Hydrogen Gesundheitsstörung Computer animation Match Metabolic pathway Chemical structure Extract Calculus (medicine) Stereoselectivity Biomolecular structure Isotopenmarkierung
Chemical element Ionenbindung Computer animation Yield (engineering) Glasses Common land Substitutionsreaktion Chemical reaction Radical (chemistry) River source Chlorine Chemistry
Conformational isomerism Area Biosynthesis Benzoic acid Vinylverbindungen Carbon (fiber) Chemical reaction Chemistry Ammonium Meat analogue Hydrogen Computer animation Halogenation Silicon dioxide Pain Biomolecular structure
so what looking like what it's looking like will see how dollars so we need everybody knows never mid-term coming up it looks like it's going to be read through Chapter 15 of them if there's all this area really hard winter and so you will know a lot of synthesis so last year we had back plus this stuff and and so last year we expect us to step and so I couldn't ask as much sentences because that takes time right whose most 2nd test so that means it's going to be more synthesis right so what you want do there's you wanted duel as much synthesis as you can so do do the saplings synthesis jumps straight at the end of each chapter there's a synthesis section mixes reactions from all the chapters you wanted do that those are the things you want practice and services pay paid questions anybody before we get started alright so Chapter 15 really different so we had a little bit terminology we're talking about the structure of radicals some terminology he bromide
I bromine and bromine a molecule
let's talk about some general features of radical reactions was in mechanisms in this chapter chained to possible mechanisms from this chapter and 3 possible reactions from this chapter so that the reader reactions were in a takeaway the news and said the says there's too much to possible mechanisms for this chapter of our rights so radicals undergo 2 ,comma reactions Iraq would signal bonds and they had 2 pipe bombs here's what they're pushing looks like you actually have seen this before it was in 1 of the chapters in 51 and when we were introducing reactivity talked about Homewood upon quake cleavage Maryland upon cleavage and I II really emphasizing it because I think this is a whole world unto itself radical chemistry the reaction the a really different starting lineups students from captain learned that OK so where would the Arab pushing is completely different so now remember doing this reaction were breaking the carbon hydrogen bonds home elliptically that means 1 electron goes to this carbon and the other electron is going a combined with the unpaired electron on tax and it looks like they're going to combining OK that's the way we do all the arrows for that and once you do there you get a C H 3 radical plus
Ajax so whatever breaking bonds in radical chemistry we're going to break it publicly of 1 electron goes to ,comma 1 electron goes to the electron at belongs to hydrogen hydrogen teach electrons and compliance with this unpaired electrons to make a new once we have those 2 electrons we have a new bond and that's the bottom right here so that's 1 type of Arab pushing and then the 2nd time is where a radical attacks a carbon-carbon double what various evil types products so again we're going break the
5 on the carbon-carbon applied bond of holy place so 1 electron spin good this car the other electrons from this carbon on the right is going a combined and looks like it's combining midair to make our and again 96 so so that's Arab pushing and of all the mechanisms that we do in this chapter are going to be some combination of that era Persian so the radical goes right here so noticeable doing these radical processes here processes here
but we start with the radical wing of the radical we start
with the radical we end with a radically parts radical mechanisms have 3 parts so I'm very likely that I will put a radical mechanism or give you more details on Monday on and you have to put things into the right spots so there is an initiation that can be 1 step forward can be multiple steps there so there's initiation there's propagation and there's termination and so if I give you a radical mechanism on this upcoming midterm I will have this already written for you initiation will have propagation and I'll have determination and and there's reactions and there's problems and sapling Chapter 15 where they have categorize reactions as initiation propagation termination also you want to look for for that for you if you have the right reaction put it in the wrong spot we don't get points for its you have to be able to recognize of what type you have take a step you have so initiation reactive intermediates generated so initiation we start with something that's not a radical and we we break the Bonhomme politically and we make to radicals that's initiation and sometimes it takes a couple steps to do that propagation interactive reacts with the stable molecule to from another actor-comedian the chain continues until the supply reactants is exhausted or the reactive intermediates destroyed so these radical change so it's like every time the reaction we get 1 molecule reacting then it starts the chain again and so every time it does or does the process it does it it's another link in the chain and termination stepped aside reactions at story reactive intermediate and I intend to slow or stop the reaction so we'll see examples of each of these I 1st
want to talk about how intonation and look at that mechanism of chlorine or bromine will react
dockings in the presence of lighter he or added peroxide to give Al kill so this the 1st reaction but we want to talk about and this is an important reaction because it allows us to take out keen that it's completely and reactive and once we put a chlorine on that al-Qaeda now we have a functional groups and now we can do we can we could turn and other functional groups in all ways that we've learned so we have an alkyl halide we can give the exit from Chapter 7 Chapter 8 Chapter 9 Chapter 10 Chapter 11 and Chapter 12 right if we just have anything for example there's nothing we can do with it it does have a functional so this allows us to put a functional group on and on reactive molecules so here's an example here but this is nothing plus chlorine and you get you get a big mixture here on this year's high temperature starts this reaction Hi Chem White usually light of a specific foreign Ministry and so on the initiators and that we're going to be using in this class are usually peroxides so this peroxide is a a free-radical initiators or just a radical initiator CD the chlorine you need a high-temperature heat light now what I normally do on my exams as I will I will show each new and that's a trigger to view to make you think OK this means it's a reaction from Chapter 15 it's a radical ran that helped you out because I'm sure as of now president right now all these reactions or
swimming in your head right now find it hard to keep them straight in some ways the 2nd example uses bromine and this is light and temperature to get this reaction goes is not necessarily easy easy to do and this reaction is much more selective will talk about why coming up you actually on only get 1 product so chlorination on selected will see that coming out on probation much more selective are excellence is a radical chain-reaction and I would do the mechanism for
example 1 and then we're going to do an abbreviated mechanism for example to pursue both of them and I am I'm not going to show I'm not initial formation of all all these products I'm just going to show you a few here at the start of the run through online booking initiation it's where is where the radical was formed to start the process going in order for a free-radical chain reaction to happen you only need 1 radical to stop at that radical sticks around a long time but any of its there is going to create new radicals that reaction will keep going keep on going so it's not when you do a radical reaction you're not hitting it with light and all the radicals performing at the same time it's use it 1 molecule at a time in every time to complete the reaction you get another link in the chain so unfair erratic formed and this is going always be where we break a weak bond right so here's some examples from the top quarter of weak wants the notice spot associated entities are all really universally well here but foreign foreign-born 38 . . 59 bromine from 46 iodine bond 36 peroxide 51 this sister Udall peroxide dye to be approximately 38 and 1 something he's all have in common besides the fact that they have on small bond Association whether they they all have in common wall I think I I think I heard it on both of these Adams have long years in there right next to each other cases so that so that the day this has long presented on pears and they're right next to each other and so what happens with those long Paris as they want to they want they would tell each other and so they want move further away because there were a there's electron electron Paulson and when they moved further away that lengthens the bond and makes it weaker right so this goes only back to 51 a strong bonds are short bonds weak want a longer bonds so electron electoral process from those of Paris is getting 1 of the 1st things pulled away from each other it's going to weaken the bonds so that's what's going on so let's throw some appears on here say could be reminded of that having too much fun drove here so did the good things good points to make about them weak bonds here I like this is I can actually break he's a little faster than they can with the with the pen from the transparency about that Abkhazia will let alone prayers going on so that makes a good but there is a good point so what we have is to Padaro Adams and the other thing that's really good is that when I have my hand on my hand is completely covering this and it's not covering it all of the assessment and edging alike about this of taboo here said you had around bonded together both with pairs so that makes a a weaker and weaker Bond in a weaker bond is easier to break OK so what we have chlorine chlorine that's honorable on Greek bonds so the radical is forms and so we're going to make a chlorine chlorine bonds are going to break it down politically so chlorine so we start in initiation we start off with the neutral molecule that's not a radical and we end up with 2 radical and that's with starts the process rolling so how do we know something's initiation step we start up to something that's not a radical and we create new radicals that's how you know his initiation propagation so what's going to happen here is we have methane Salter on methane would draw out 1 of the bonds from FAA and the chlorine radical the reformed in the initiation there were going to do the same error person we did on the previous page but the chloride chlorine radical is going to abstract that hydrogen but remember when we do radical reactions within a break each bond of politically so we break the carbon hydrogen bonds
,comma gets 1 electron Heidi gets the 1 electron electron that hydrogen gets combines with the unpaired electron inclined to make a new hydrogen chlorine bond so we get hydrochloric acid is and there the methyl radical that we just for it's going grab so we're going to break this chlorine .period Bonhomme Oolitic please the electron from declaring on the left is going a combined with the unpaired electron on the mantel radical and we're going to get our and that's the other thing the going to see a propagation stuff so that someone chain that's 1 link in the chain and as you can see that what we've done here is we've regenerated the radical that we started with so this is going to come in and it's going there's art there's a link in the chain it's going to come in it's going to do it again it's going to keep cycling through so we region the radical we started with yet but the you cannot be sure that with that termination step of on the show that just a 2nd Serie regenerate the radical that he started with and the other thing I want you to notice is that we've always keeping the same number of articles in the propagation steps so in this 1 we start with the radical and we ended with a radical here we start with the radical and individual molecules end with a radical mineral or not the molecule without with all electrons so staring a radical and with the radical start with the radical and with the radical so wait years sorting those problems and settling into boxes that's what you're looking for the number of radical stays the same 1 here 1 year and 1 here 1 here In the 1st when we started with 9 and made 2 that's what makes that initiation stuff so no to found the number of radicals stays the same In propagation steps so that different 1 make sure that you look for them now termination this is really the opposite of initiation initiation you start with something that's not a radical idea break into 2 in termination you combine to radicals and you make it into something that's not an article that's termination stuff so that's what you look for when you're doing you're sorting so free what any radical that we have here came mind with any other article so for example we can have some we cannot claim radical to answer your questions combining with enough so it's like that we could have a that would give you the product they were going to get anywhere insist made by different pathways that metal chloride we clearly have to level radicals combining failed so that will give you a thing that we can also have to radicals recombined erases these ending being
inside products that you get well the first one is not a site product this is the 3rd comes psychotic but certainly thing is not something that we're trying to make OK and so on you it's only if we don't get very much of this termination steps because let's imagine that we start off with 1 molecule of chlorine breaking OK so let's imagine we have just 1 molecule do this so we only have to right to Quarry radicals 1 of chances of those 2 chlorine radicals from the beginning to be stirring in reaction there going to be moving around doing this reaction over and over again determined in the propagation the chance of those to actually add into interacting colliding and recombining is very small so there will be a lot more propagation then there will be a termination but you still don't get sidetracked OK and so on that's why it's not a very complete and but it's not it's very it's not very clean reaction because them we don't want you know only no one's going to want to have to separate all these possible products use you see we have a lot here we have enough of chloride now and you can imagine she to form to methylene arm to form this 1 right here and we would just a radical would come in remove another Proton from methyl chloride that's how we will get some of this on to get this this is chloroform we would have I'm a radical ,comma remove another hydrogen from carbon here and we there without some form this you could do that 4 times you can replace all 4 hydrogen is with chlorine and here this product right here would be from the Ethyl Ethel that we find in our determinations step so you get a lot of more its kind messy reaction here so that the competing
propagation step here let me I'll show all show formation of the the dike thing here you can see what I'm talking about here if this comes in and grab a proton instead of from methane in the grabs a proton from methyl chloride then he formed radical analysts that radical gonna do that radical is going to and coming gravel instead come in right here where are we going to come in here is going to ground coriander take it died for other things must show that so kind of a messy reaction here notice my single-minded heroes here comparison of form so when we say we said about 80 per cent beginning
about 80 per cent methyl chloride in this reaction 20 per cent of these other little side parts they have to be separated 1 of the ways to get this reaction to go a little bit better and a little bit cleaner is to keep that keep the concentration of the site products while keep concentration well by using a large excessive nothing paroxysms methods of gas you would use a large excessive methane and then that will increase the amount of methyl chloride again and some of other little side products will be of much less question about that mechanism anybody alright so as we say in the next stages isn't a very good reaction because it's not very clean it's
not the best way to synthesize outfield nationwide there are better ways but it's so useful because it is the only way they converted the and the came into our reactive compound it's the only way that we know how to take in the AL came light propane anything now and nothing and I functional group on what's the point of chlorine or bromine on there now we can take that and do all the other reactions we know we can do without the but until we do that we were stuck so this is even it's not a very good reaction is the only way it's the only thing we have so another better way to synthesize alkyl chlorides we learned in chapter 10 right if we do this we will get a million little side products so that's what we would do if we want to make an alkyl halide but for killed bromides we would use on HBO so there are better ways what's the difference here are we starting with a compound that has that doesn't have a functional groups I know of where we're starting with a compound that's now Keenan has a functional group it has a functional group that can be converted into other functional groups so this is different it's a better way to make alkyl halide you are starting with material has a functional group right here there's a functional group that Elkins a functional groups and so it converting it to another function we have in our team have no function this has no functional groups so we can take days and remove that hotel is it has a at 15 so this is the only way that we have to put it .period Afonso group on and then once we do that we can convert into other things question so far anybody let's look at the 2nd mechanism this was a lot cleaner
so we take tertiary butane bromine light and heat In that store products a single product here we don't get a lot of different products here are so initiation a radical form we always break a weak bond we got a weak bond here did I not lead time start OK so the weeklong that's easy break week Bonhomme melodically we started off with unknown radical radicals now I again would make the point that not all of the bromine but not all of the molecular bromine bonds are going break just a few of them not all of event where we only really require 1 to break and that's enough to get all of our starting material converted into products so propagation and I drew some of these are ready to make it a little easier she probably drawing upon a little longer to go here futile radical plus HBO and amateur futile radical comes in it's through the same mechanism here grabs of growing so so we still have grown Bromo we still have molecular bromine so that the broadest bromine in here that hasn't been broken apart and this is going to come and get it coming grab a premier from that and when he does that informs our product and we always want for this it's going to it's going to regenerate the radical that we started with propagation so what the last here is going to be regenerating the radical that we started with and definitely wanna look for that so this 1 here that's what we started with and now it's been a cycle back through so most of the bromine is going to be broken apart this way not this way questions I hear a lot of time both
I will do all identify the effective annual if it means 1 of 2 things I the school quickly or administered about that that's looking too much like a dark rooms from the time of the better OK we generate the radical that we started with alright termination radicals destroyed during destroyed by recombining recombine any radicals here you feel it here's 3 possible and by the way on the test I will have an initiation section I will have a propagation termination and what I always do on the test as they say show only 1 termination that's all I want to see you don't have to draw all 3 I just want see 1 so everyone is thinking like investments which you can quickly direct so possible mechanism radical held the nation's
5 will have some sort of out they will have read the bromine and chlorine in line with the new ball that's 1 possible mechanism for furniture sorry I want to say something about selectivity very selective with bromine right in terms of the bromine is a much more selective reagent think Lorena Oregon explain why that it's bucket so let's look at it we've got 1 tertiary hydrogen let's remind ourselves of the church had tertiary hydrogen is a charter to assure hydrogen as a bonded to a tertiary carbon that carbon responded to 3 other carbon tertiary car and we have now many primary hydrogen 9 equivalent to tertiary heritage are primary divisions 9 primary origins so we've got 91 ratio of 2 of primary to tertiary origins and we still get no primary hydrogen is extracted we get no product that comes from a primary hydrogen being extracted so statistically you are 9 times as likely but you don't get you know what did not get any don't get any primary hydrogen instructors so you don't get any of this product to this product would result from a primary hydrogen being struck is any 1 of those lines would give you this plan and you don't get any of that so that's pretty big extra that None of that product is for us so we need to really explain why there's
there's 2 factors that we need to talk about explained his number 1 is a relative stability is of the radicals forms and I'm so we have a tertiary radical more stable than secondary radical more stable than primary more stable than that radical OK so if we remove 1 of those primary Huygens were forming
a primary radical and so maybe not surprising in that we don't get any that form the lockers we know their primary radicals very unstable similar to cover Karen primaries variance stable and the other thing it's not obvious is that we have to look at the ease in which the different regions are removed and in order to do this you can look at the bond dissociation energies and energy of activation so we actually have to do some calculations were not any calculations but I want to show you that with the relative rates of heightened abstraction by halogen atoms for bromine primary as 1 to 82 to 1 thousand 640 so terse tertiary area for me it tertiary radical is 1 thousand 640 times more likely than forming a primary with a brilliant and since we only have a 91 ratio there's not a chance statistically that we're going to removing 1 of those primary origins the selectivity for tertiary is way too great of chlorine on the other hand religious relative rates will have 1 from primary 2 . 5 and OK so if we did this exact same reaction with chlorine we will get some of the primary prize Friday and that's because there's only afford 1 on selectively for tertiary over primary dates for no 1 and we have 9 times the number of primary problems so we will get primary here so much more and much less selective I you're beginning to see why I'd I tend to favor bromine because he a better living where it works better in this reaction is better a lot of different reaction to attend a favor supplies of roaming I had so much more selective it seems like it's just should have to do with copycat instability but it's not remember were doing other things in this reaction so and if you can be sure that if you compare transition states and activation energies for the extraction of a hydrogen atom by Brawley radical forces according likely you will find that number 1 extraction of a hydrogen atom by bromine is Endo through Wall extraction of a hydrogen atom by chlorine is ex-soldier makes this sounds crazy difficult it's really not that bad on a number to the transition states for the editor maker from a nation of a larger to energy difference and those for the acts of terror coronation even tho In nationally on the page
but even all the energy difference in the products is the same involving is Ivan while wrapping around that right so let's see if I can explain this graphically here for you so what we stand on the previous page in this construction of a hydrogen atom by bromine is end-of-term acknowledge structure of a hydrogen atom by acquiring his excellent so here it is How came and chlorine XO Thurman so that this radical here is down here and then if we do bromine its end of the effects of this radical is hiring energy OK so let's labeled this is an excellent atomic reaction and this is the end of the week reaction the rate of reaction is going to have to do with the height of energy very little we know about the structure of the transition state in acts of military action doesn't look more like the reactants for that reaction on the part it's constant energy to or starting off with 1 thing we're starting off with 1 thing we have a variant of the wreck reaction on the difference in the area between these transitions status so close because it looks more like the young than it does the radical very very close so what that means is that when you do the coronation you're going to be equally likely to take all 3 of these pathways and yes the red the red halfway down here is low on energy but these are all very close by so they're all accessible Over here we have an and action by him as possible we know that in and of direct reaction to the transition state looks more alive the products of that reactions and so since there is a big energy difference here between these 3 products has also been the big energy difference here between the transition states and so you can start to see now that we've probably elimination this lower energy pathways of is so solo and these are much too high for it to overcome that energy barrier OK so all the molecules take pathway this is a big energy difference here here there's not it's a small energy difference so we would definitely want a label that a little better here and label that so Thurrock reaction therefore the transition state resembles there were only looking at 1 step here Jesus is resembles our reactants more than products In an end Derrick reaction to the transition state resembles products more than reactants and so if you look here and this is a really small energy difference between these guys the tour to tiny little arrows are never going to be all see those that very small energy difference it is less than 1 takeout from so 3 very accessible transition states and so you're going to get you going to get out of a big matches here and here are these guys here this is among a large energy difference and what we have here this is about I may be exaggerated a little bit more and this is to house from all and that's enough that you and so if you if you had to take out from all if you got tertiary if you got tertiary versus primary that's 2 cows from posts to retire K calls all that's a really large energy difference for transition states so too when we had the larger energy difference here this 1 has a much bigger energy difference therefore the rates the reactions will be markedly different and this is a really good example of the points that we're talking about a reaction it does not have to do with the intermediates these intermediates and these areas have the same energy difference on it and if it was only because of that and we would have the same product outcome whether release from inquiry it has to do with the height of the transition state here that's what that's whiskey currently here's an example here to show you what this means the difference lies in Seoul activities so here we have rumination period chlorination with brominated we get 1 product 82 per cent With I'm chlorination we had 26 per cent this product 22 per cent this product 22 per cent and this product 14 per cent this product and 17 per cent and you can actually predict these person percentages by taking into account the differences selectively chlorine versus the number of hydrogen is inhabited actually calculate these differences the textbook we had had you do that on this text but doesn't have signed off on that and have learned that you'll be
glad about that we're very glad that the yield in glass far-right
questions Bond brominated about for chlorination of that's reaction number 1 from this chapter radical substitutes events elegant Alec Bedser that's reaction number 2 in this chapter and we are going to skip the mechanism here but you need to know the reaction for sentences why am I having the mechanism it's a confusing mechanism in has single-handed arrows and double-headed arrows it's just so hard to wrap your head around when you're just starting again chemistry for the 1st time and I know that because I remember having to memorize and then a lot of mechanisms that I didn't really need to memorize OK so I'm I'm I'm having selectively having you memorizes things as little as possible so we're skipping the mechanism and you don't know to communities need to know that the common elements of radicals are both more
stable than tertiary radical we know the more stable the radical the pasta can be formed so I hired him wanted to be the benzoate Grella carbon can be preferentially be substituted in analogy nation reaction so again beat these guys are more stable than tertiary so that means that if you have a choice between removing a tertiary hydrogen or silica Alec then silica Alec Baldwin so bad here's some examples here the odd we can make this radical right here we will form of primary radical only for that 1 and then if we carried out on we will get over a substituted principle so the bromine will go in the band's opposition no where else can you put that probably if we have a and then we can put that we have a choice between vinyl hydrogen or OK so here's vinyl right here are eager for an area that not only got out of that we for right so that's way better so that means that from we confirmed our radical and we can convert that into our overall so who sees the competing reaction that conform with this things to who sees another reaction it's competing with that From Chapter 10 yeah ad and then you don't rumination about clean is extremely fast reaction you guys did this in the lab you have asked there's really so how are we going to do this when we can do this just as fast OK so I'm really give you different region for this were not going to use this really really give you a special reagent for this that I want you use instead and that's because we have competing reactions here we can't
with bromine we can form up ammonium ion let's remember this we don't forget there's this is Mitchell to material right not to bring up an unpleasant subject but we nobody likes taking tests they graduate school I'm in chemistry you take 1 year of classes and then you working a lab for the rest of the time .period earned a Ph.D. and I remember thinking at the time I've only got 1 more year of classes in the I cannot do this for 2 years I've discussed so burned out taking tests so I haven't had a ticket ascension into beautiful thing because nobody likes taking tests are right so they whoever that's pain so that's competing reaction that's a competing very fast reaction and so really what's not use bromine for this even though obstinate uses it's a lot synthesis I want you to not use this region in so that that's a reason why I will stop right there and I will we will finish Chapter 15 next time so this
is the reagent I want you to use instead