Lecture 23: Electrophilic Aromatic Substitution

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Lecture 23: Electrophilic Aromatic Substitution
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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: 00:47 - Molecular Orbital Picture for Benzene 28:23 - Some Chemical Consequences of Aromaticity 36:26 - Nomenclature 40:26 - Electrophilic Aromatic Substitution 44:09 - Chlorination & Bromination Benzene
Ionenbindung Blood vessel Chain (unit) Atomic orbital Complication (medicine) Aromaticity Atomic number Benzene Atomic orbital Deterrence (legal) Electron Fire Stratotyp Conjugated system Molecularity Pilot experiment 11 (number) Carbon (fiber) Hybridisierung <Chemie> Spawn (biology) Animal trapping Food additive Systemic therapy Computer animation Aromatic hydrocarbon Covalent bond Chemical compound Chemical structure
Stop codon Ice shelf Ionenbindung Resonance (chemistry) Meat Atomic number Benzene Reactivity (chemistry) Atomic orbital Electron Periodate Setzen <Verfahrenstechnik> Molecularity Pilot experiment Singulettzustand Walking Carbon (fiber) Topicity Hybridisierung <Chemie> River source Fiber Food additive Korken Hydrogen Computer animation Resin Covalent bond Aromatic hydrocarbon Iron Chemical structure Devolution (biology)
Famotidine Chemical property Resonance (chemistry) Atomic orbital Operon Aromatase Molecule Electron Nomifensine Spring (hydrology) Conjugated system Periodate Pilot experiment Stickstoffatom Octane rating Gas Walking Carbon (fiber) Sulfur Hybridisierung <Chemie> Protonation River source Lone pair Systemic therapy Hydrogen Feed (film) Acid Computer animation Initiation (chemistry) Chemical compound Covalent bond Aromatic hydrocarbon Proteinkinase A Chemical structure Cobaltoxide Base (chemistry) Handelsdünger
Ionenbindung Styrol Set (abstract data type) Heredity Benzene Chemistry Electron Nomifensine Phenol Suspension (chemistry) Ausgangsgestein Area Metal Substituent Potenz <Homöopathie> Stickstoffatom Gas Deep sea Erdrutsch Systemic therapy Lone pair Song of Songs Computer animation Functional group Chemical compound Aromatic hydrocarbon Chemical structure Thermoforming
Molecule Naturstoff Computer animation Recreational drug use Gasoline Lactitol Aromatic hydrocarbon Operon Chemical reaction Aromaticity Chemistry Food additive
Sense District Reaction mechanism Substitutionsreaktion Chemical plant Titration Chlorine Benzene Ammonium Electron Fire Isoliergas Chemical reactor Filler (materials) Octane rating Alkylation Walking Carbon (fiber) Chemical reaction Food additive Hydrogen Hypobromite Gesundheitsstörung Acid Computer animation Resin Aromatic hydrocarbon Iron Chemical compound Chemical structure Bromine
that's a really and started a fire on the police said Parliament's quietly on recent Fini's chapters 17 today and make a search operating their started the better fighter and quite did earlier want the lecturing up until the 11th hour on Friday right considering our finals on Monday and get this thing turned out did we look different molecular orbital picture of benzene we can explain its vessel stability so we toured the molecular orbitals for benzene using the Cross circle and circles is just an easy way to I'm John molecular orbitals specific compounds into oblivion the hearing here with 1 of its vertices and at each juncture we have like arrivals at the halfway point here we have the urinals before they combined to make the pie molecular orbitals and if we have a cold bonding shallots especially stable does that mean that every time we want to figure out some things aromatic or not we have to draw the molecular now that we can actually use Hubble's role which is a little bit of a shorthand way of dealing with this so what rules states any conjugated motto cyclic Pauline so there is plainer and has was due electrons with an equal 0 1 2 etc. will exhibit a special stability associated with their electricity where rents through a bunch of examples so you see what I'm talking about here systems with 4 electrons in Thai aromatic for the less stable than the open chain counterpart so we were right at the ring had something to do with it ,comma but did you know there's some complications here because we have to have a ring they have there has to be conjugated and and has to be playing OK so those things are all going to come into play so to be aromatic compound must satisfy all 4 rules were just going to go through all 4 rules here structure must be cyclic that's the 1st rule look for fish 2nd each item in the ring was Tavern hybridized the orbital so I know the words we have to have either as the three-year that ever the jurors the hybridization attempt on hybridized the structure must be cleaner to elaborate continues overlap apparel roles that's the tricky part sometimes with some of these rings and the localization by electrons over the ring must result in lowering of electron energy so if you have foreign post pry electrons it's in a aromatic and we have special stability over and above anything we can have her normal compound that's aromatic if we have something that's an entire American would have foreign pilot trounced and I would be extremely instability OK so those are the 2 things and everything else is neither aromatic her entire life just as normal normal stability so wearing go through each of these rules 1 at a time if it satisfies the rolling move onto the next 1 of a doesn't satisfy rule then we are we stopped at sea the aromatic grandparents to decide whether something's aromatic grant aromatic we have to go through all of the previous roles so let's let's go take a look at the 2 previous examples again now that we have this new understanding of what accounts for the to so sigh computer dying marvel at their 1st rule structure must be cyclic OK all of these essential excellence for the little 1 here for role 1 all of these will do them all at the same time that all of them a cyclic roll over to each other in the ring was Tavern on hybridized the orbital alright this oversight of the dying is located in Manhattan as part of a double bond and that means it hasn't hybridized fuel tank there so these guys as the 2 as the 2 every single carbon as B to S P 2 S P 2 every single carpet so they all satisfy rule number 2 which means we get to move on to rule number 3 will number 3 structure must be plainer To Laughter Continues overlap of parallel the hurdles it sometimes can be difficult to decide what I would also tell you here's our rule of thumb for this class if all of the atoms in the ring R S P 2 hybridized and you have a six-member drink or below lower it's only when you get a larger rings that Adams can bend out of plenary when they're to harbor so that's going to make it a little easier for us our so number 3 is the is it plainer so this is a a member during were all the Anza sp to hybridize so it is definitely playing that means we can't select chances to electrons per bond so there's a lot of flora and high electrons which satisfies the Rule of Four imply where on equals 1 and so there this is 1 of the and intact aromatic so this is extremely unstable so this is the 1 we had to trap and frozen article an entire the entire OK so we know Bentsen's aromatic policy as as we go through we will whether it satisfies the rules so that the rule was place planar if all items in the ringers sp to high and its 6 bring below it is player so this satisfies rule number 3 and we count electrons there's 2 for every pie so we have 6 pilot problems and that satisfies 4 and close to pie electrons where equals 1 and so
therefore this is questions so far yet whenever you need it yes exactly as whatever you needed to people so if you have an even number of electrons it's going to satisfy 1 of these 2 equations always OK so even number electrons deleted before World War II and in Piura or for imposed to fight so it's whatever 1 it satisfies our rights however Cyclops a chattering isn't clear we talked about this at the very 1st created Chapter 16 is cycle opted player know something not later therefore it's neither aromatic her entire whenever we need to we need to satisfy all of the all 4 rules when he needs satisfy 1 2 and 3 and then we can electrons if we don't satisfy any that from the 1 2 or 3 minutes neither aromatic the entire amount so this would be a business I like a typical polling normal reactivity of a typical following I write cycle deck upon taking on his employer well that's the way Stronach will player isn't really Plater here's how you know that this decision is not playing draw the hydrogen is in on this year's problems here and you'll see a little problem I can't even drop what they're right on top of each other to even rather so so this rain when you get to larger rings can kind of band out of play narrative to account for problems like that this cannot possibly be playing because all sides hydrogen to the right on directly on top of each other so this is also not it has the magic number still for interest to finance the aromatic magic number but it and if it was planted it would be a lot but it is not playing so it is not insider aromatic the entire matter again typical Pauline so the question always comes out how are we supposed to decide on an exam whether these things the planar not out and and the answer to that is that I will stick with 6 six-member during below typically so they now as otherwise they it might not be obvious at all what's going on here are about 18 annually in this we know it has special stability a in you can see that and so it's certainly it's entering certainly never to all the 2 hybridized of 3 might not know because it's a large ring is cleaner and if we draw the hydrogen in here we can see that there's actually room for them not like in the previous example there's definitely room for these hydrogen here so this is plain if we count up the electrons we have 18 electrons you know and and how do you know whether it's sad said the rule is in a multiple of 14 is not a multiple of 4 so it's going satisfied on and plus 2 5 where any calls for therefore it is here so now everything on the previous slide that we're scratching our heads on this is explained take questions anybody you are right bionic Sequent Pauline's can also be aromatics and there's other things really bring types that we need to consider it what's good here really follow the same steps here I step 1 for each of these Is it entering yesterday is yesterday yesterday is yesterday was that the easiest 1 OK number 2 oral all atoms in the ring as he to hybridize have this first one no stop here but take no so you stop here it's a normal Pauline it's not aromatic it is not entirely Our right now let's look together let's look at the 2nd 1 in our lands in the ring as the 2 high-rise if I answered that question in chapter 1 you would say no when Nafta we did Chapter 16 we realized that if this is residents stabilized and I'm just going to draw 1 resident structure there are many but if this is residents stabilized notice once we draw the resin structure here that we started off with something that in Chapter 1 we would have expected this carbon to be as 3 hybridized now we move this over to this residence structure we see now others a double bond there so it can be as the 3 but idolized has to be a speedy so the answer to this 1 is all atoms are ST to hybridize all Adams heaven and hybridized fuel so so what that means is what that really means what all scroll down will scroll back up again is is is this is what it looks like right here if there wasn't a resonance stabilizes would be as 3 so in order to become a residents stabilized and there's a real hybridization has to take place here that carbon starts off as as P 3 but ends up as as too and when it goes from S P 3 as to it takes that long period puts it in a few orbital that curable
notices parallel to all these so we can get overlap only around so this 1 8 8 gets a lot back from that little maneuver here so we can now we overlap all the way around here Top and Bottom overlapping here having fun without him there yeah out just like that OK so that's what happens there so was so let's keep let's go back and I'm so we passed through members 3 are we in hospital number 3 with council member to our happens in real number 3 is a and what's are ill effects if all Adams a as 2 hybridize and it's 6 Marina below its pointer so yes a to check for number 3 then we count electrons so we have to gone and long hair is going into what P or Wilson recounts 6 altogether 6 is a magic number so this is a 6 pints electrons that satisfies our foreign plus to here for ceremony therefore it has special stability now don't get me wrong this fiber of during it's in an iron it's not as stable as benzene but it's especially stable Fernando especially stable for persons so far are really about this next 1 here are all atoms in the ring and as the 2 hybridized yet ,comma Kennedy's sp to hybridize who hasn't if orbital is plain error latches we've got our arms and there was this really do a 1 2 3 here is definitely playing opposite the six-member renewable Welch is so that we can electrons 2 double bond for apply electrons OK that's not a good 1 that's a for in Hi electrons where N equals 1 therefore this is entire therefore extremely unstable low-temperature attracted trapped in frozen are gone it's 1 of those OK so extremely unstable and tired here we have here we have a a seven-member ordering so now it's going to start to get tricky whether we decide whether something is aromatic meat whether it's plain or not but I well tell you for this 1 here is that all that is certainly a recipe to hybridized this is and if we cannot electrons we have 6 pilot from 6 is a magic number that is foreign post to by electrons where and equals 1 and therefore this is it is not as it is not as stable as benzene but is X really stable Carver Place a very unusually stable carbon caps all right and I wanted to do was undertaken to ones here you know we've been going through by checking the rules you can also do the of frost circling draw the molecular Robles was looking let's take a look at these 2 here analysts was too fast circle on the next page just to show you that's what really what's going on here as were checking these roles as a shorthand way of undoing the frost circles so trust circle we draw the out with the vertices down so that's what I've done near the halfway point that way .period is is actually a little bit of all here it's not doesn't illustrated that it doesn't go through these bonds here it goes a little bit about and so what we're doing here is we're combining 5 atomic orbitals there when we do that we get 5 molecular orbitals never has to say this shame so there's 1 2 3 4 5 so there's 1 you decide on the topic above this line is on Thai bonding Vullo this line is bonding and what we want Ferreira to cities of filled bonding shall yes show me a on not not when there's an odd number like this there's no way to do that right now I and that's getting like really hardcore Pete Carroll outside the scope of this class OK so this is so-so which combine 5 the term girls by molecular-level Samuel electrons we have for this 1 we have for right let's fill up our and molecular orbitals 1 2 lowest energy 1st cared the span degenerate orbitals we all want each we do we have a filled bonding shelf unfiltered bonding shelf it's going to be entire alright if we go down here we have the same thing everything's exactly the same were combining 5 key atomic In rumor only looking at the Pine molecular orbitals without looking at Sigma we get fired we have to force 6 electoral most energy 1st fans generals get 1 each and we start to fill up that's when 2 this is 3 this is foreign and we go back and fill 5 and 6 fielded bonding shell especially stable so pretty amazing that medical
came up with this I think are we can also and we can also and extend this to Hatteras cycles so I had the cycle is of paramount as any evidence of carbon hydrogen and so like things like oxygen nitrogen sulfur there's a bunch of different ones you can also have on there's Boris cycles and we can also extend this issue Hatteras cycles so let's look at that on the next page German which of the following year in cycles are alright so we knew what we should recognize this first one this is parodying rightly use that a lot in Chapter 9 This is serious and you you we've heard that ths Tatra Hydro for so we hydrogenated this double bond this double 1 that would add 4 hydrogen stature Hydro fear and so that's where that comes from and so let's see if the fretted about so reducing their reducing steps step 1 is everything entering yes yes and yes step 2 is every Adams as feed to hybridize certainly from purity initiatives for for all well I mean think about it if we want to draw resident structures for this which we do if you look at that oxygen right now but that oxygen right now as part of a double bond so it has to be asked to hybridize right so definitely all Adams sp 2 Harvard eyes and and likewise with parolee wants to do the same thing so with their newfound knowledge from Chapter 16 we would we would absolutely some say that that nitrogen and that oxygen or to Harvard L right so we determined that although we determined that all of these are unnecessary to hybridize all have rings the six-member during below so automatically 9 that's the number 3 is is it clear yes they all play OK and so here's what's happening here when we do this when we drew these residents structures or scroll down and all scroll back up again here would be the oxygen after Chapter 1 we would expect S P 3 but then we realized we get to Chapter 16 it can be as the 3 it it's residents stabilized so without oxygen does is it puts 1 will parent key orbital and it becomes sp to hybridize and and for all this the same thing it it before the Highbury hybridization it's S P 3 but it really greatly benefits from that resonance stabilization and also others can enable these compounds to be aromatic so so that's a good that's a good payoff and so on once that happens now we have this long hair overlapping there just like that here is here is appearing the long is not part of that is not a system it's factually perpendicular this isn't and as feed to an orbital does not it does not contribute chairman is then so we kind of have to know where the lone pairs are so as as you can see for around fury 1 long periods is part of their the the rating and 1 care is not OK so this it does not contributed to the undue localized electrons in the ring and this is important when you're starting to close or doing this next step which is counting electrons number 4 for all of these so far during the duration of that has to long hair swirling account 1 of long years for for this aromatic ring here so this is turning out to be aromatic consistently 6 by electrons and likewise here this long period here is going to kick into makes 6 pilot from so that's aromatic for nitrogen we certainly don't count that won't care because it can contribute to this spring system here because it's perpendicular and neither can act so that what that means is that you're referring several accounting and 1 of the lone here so let's count electrons for purity
and we don't count the lone pair at all it's not involve services 6 pilot therefore aromatic Syria angrily counting 1 long hair so this would also be 6 pilot for therefore for parole again 2 4 6 6 pilot programs therefore hearing questions so I think the Hatteras cycles are the most tricky but of course and most of Europe by operators and inheritors cycles played for predominant depraved favored fertilizer sales of nets we need to know what's going on here with these guys my some chemical consequences of aromatase yes will fearing yet going ahead and throw that in there you guys want to draw that I loved doing that this for the student but that is Bahrain chemical consequences earned 2 season's top answered some comments usually is selling because the Kon-Tiki bases the aromatic other problems are much less acidic than expected because the proclamation to swap ceremony also Ramona Proton and then it's going to make the compound entire it's that that's going to be much much much less acidic than alright so some things to consider Our isolates compared this guy here PKA those protons verses a similar system only 1 of these protons the difference in PKA PKA is 15 year over here he did 45 so we're not just talking 30 times more acidic we're talking tender the 30th time sources that would be a really hard thing to explain before each cover Chapter 17 and so let's look at the conjugate it's always a good idea when were comparing the city's look at the conjugate base here's our country amazing you recognize that molecule From the previous page this is our resident stabilized residents stabilized class so that Carter could face a much much much more stable and you would typically expect because of their emergency and that's why it's 10 of the 13 times were sitting on over here we just have resonance stabilization there's nowhere Madison are excellent so so very surprising results but cycles of interesting Aceves properties based on merit to save the cons gasses and basis for role it is much less basic purity alright so let's look careless try here so talk about basis city we're talking about how willing is this nitrogen to donate its electoral how willing is security to donated electric we know appeared in donate electrons beside over Oregon chapter 9 but how about her role the 2nd 1 and only electrons we think but joint like France is no longer this so it's not going want to do that so PKA conjugate acid there's minus 3 . 8 and PKA of the college the acid it is about 5 so that means that this is a much stronger base and so the reason is that is that the lone pair is part of Iraq by system so
you lose electricity when nitrogen is promulgated for on parenting and that won't hair is In a speech to rules is perpendicular to the aromatic price systems so it's not involved at all but no effect at all when sets for the lone pair it is not part of the aromatic system the it is still aromatic after its 1st the price so that helps us and knowing that about area to see is going to help us make good decisions about the compounds like this will do we will come back to this in chapter and 25 In 51 say so on maybe flagged this to come back and look at this right before we study chapter of the 25 barring another really interesting compound is this compound here it's a cycle and the China worldwide and it's actually ionic this is an ionic compounds where we have a joint as it was like that it's actually on and so was the the structure of this in it's really cool because what we have here is this 7 terrain and we saw on a previous page this is their area and then there's the Carolinas bromide so so much power inheritance of you this compound found that bond it those electrons are transferred completely to the bromine so that the size this compound could be Ireland so this is aromatic it's I actually got a special name it's called Ettrick Killian liar and don't need to know that but it sounds cool and I believe this is a really deep deep deep blue collar and I'm so the payoff here is sound is not aromatic in its covalent form so some really cool interesting things on acid-base chemistry based on the rotisserie but we are going to skip this challenge question I think we might do at the review might do next week but on China by as much time as I can right now for Chapter 18 so this slide right past very briefly we're going to talk about nomenclature so since there's no riding on this page well against supplementing of time delay that there's some merit raise you need to know the name of the rain that we won't we use as a parent so if a benzene ring as a metal attached to toluene if event has an item group taxes nitrobenzene pretty straightforward here event as an OCA analysts all favor as any to attach to animal and it hasn't always attaches phenol this is styrene we saw this way back in the spectroscopy chapter this is Ben Salah hired suspend sewer gasses and the suspense electronic surveillance you just need to know the name of because we're actually going to use the names in nomenclature we talked about over the matter terrible did Chapter 16 but I'll remind you of all 4 auto means there is that once you relationship this is the 1st to substituent song benzene ring terror as this is that we can use P 4 short there's I 1 relationship between the 2 substituent and demanded there is a on 1 3 relationship and that is Our so I if we numbered starting from final we do because that's the parent 1 2 3 4 5 6 we can use numbers or we can use of automatic so this would be offered a position this would be mad and this would be pair if 1 of his assistants can be ,comma
name the name is used as a parent and that incorporated Institute is given the 1 position that the benzene ring as 2 or more substituent substituent odd numbers as more than 2 if there's to EU can use characters 3 groups on the benzene ring you don't use often carry you only use or don't care when there's 2 just skylight system trams we only use that just were talking about so this 1 for example here of all word don't throw final or you can write it as to Bromo both of those are acceptable means for that compound by the 2nd 1 here has 3 substituent so we can't use author or pair this would be 2 3 died for inland not or demented died 4 0 here worth matter declaration analysts but kept so let's put a big action that that's as much as we're going to get into nomenclature benzene rings that are excellent as saying that we're going to start Chapter 18 today which I'm thrilled about and now this is a good time to ask questions while receiving any money I rights it's a beautiful thing on the last chapter
guys this exciting on your you're almost
two-thirds of the way down was the question where all right
there yeah so gasoline with questions about what if you have a larger rings they usually will try to build and out of linearity if there's going to be entire amount we don't see too many entire aromatic large rings because they usually can be bend way so that all the bits of the not playing so lover of ring is not going to become if it has a choice of being cleaner an operator is not going to be appointed to be Ontario it will avoid an entire city at all costs because remember all molecules are trying to get more stable are we altering again were stable preacher right OK so we are absolutely blown away by the stability of aromatic compounds we think but now that they don't do anything they do there's a lot of reactions that they do and that's important because a lot of drugs containing aromatic raise a lot of important natural products contain aromatic rings so we need the government to chemistry so they do do chemistry it's just different chemistry so
here reactions renewed talk about in this chapter
In this order so what does benzene due basically the most characteristic reaction is leptophilic aromatic substitution there we could also do nucleophilic aromatic substitution we're going to talk about that next week that's a new part of Chapter 4 of the new part of this 4th edition I will give you plenty of problems to cover that if you if you don't have the 4th edition is not a big deal but most characteristic reaction is for the benzene ring to act as a nuclear file that would be a leptophilic aromatic substitution when keep doing the same thing OK these guys are the elective files are generic electrified the plants so what happens when we do bromine and FEB are afraid that is they brominated ship so we're using the same old worsen using the same wherever were not getting the same product that we got from Chapter 10 OK there's titration government denied tration were going to do so nation so this is something pretty new worlds Menadue Frieda crafts alkylation Friel crafts installations there's real across alkylation and only a few across insulation so we have gone out of a possible let's see how many do we have here 5 but 1 of these mechanisms will be on the final they're all they're very similar and the only thing that's different is when we make the and the electrified after we make electrified while the rest of the reaction is the same not that guaranteed have 1 of these guys on the final mechanism Bahrain but still little review here chlorination bro relation of benzene in Chapter 2 alright so we needed we made a 1 Dybul compound in way we remember that and that was elected filler conditions via of ammonium ion if you have no idea what abroad line is you do crammed everything the day before the midterm jails and it's all gone OK so that's Chapter 10 now what do we do the same thing with benzene wine I will tell you why no elective condition why don't we get elected village edition it makes it makes is Eratosthenes Torricelli interim riders is not an error to city is gone if we did that reaction there is no reason for that reaction to happen it's an uphill reaction and so what we do instead is a leptophilic aromatic substitution show they share 1 word ,comma that's the only thing that's the same that's a better that's a much better product because we're still Our psychotic which we never worry that except for the 1st time we do reaction is aged people the are of electoral feel like aromatic substitution non-electrical condition all right so they do the mechanism really did mechanism for all reactions on the on the front page that we just had and then we're going to talk about so well there's a lot more to this reaction and the these reactions than that so often the mechanism in the 1st step is to make the the electrified also bromine on its own is not elected Philip enough so we have to kind of stupid to make it more electrical wiring reactors stupid up spending so stated right it wiser reactive it's not souped up so we had to do that there's a remedial we are Lewis acid bayern would like to to very much like to have a electrons in its so Soto it's a nice Lewis acid so you know Lewis acid-base reaction there will be a negative charge on iron it will be a positive charge of bromine and in what that does for us is it polarizes the I am really polarizes the sponsored makes it elective Philip when we do that so it polarizes this 1 that makes it more electrifying alright right in the 2nd step benzene attacks elective ultimate resident stabilize ,comma Qatar and this will be the same for all the fire reactions on the previous page this will be the same the 3rd step the 3rd part of the dates of the actual be same so the only difference is going to be this parts of Asia it's really not as much as you think it is so so what strongest right right so this is going to have a it's going to attack the bromine were going to break the bromine bromine von this is the slow rate determined steps we're breaking a rotisserie and making a cop accounting so makes absolutely good sense that this is the rate determined steps so just like collectively conditions from Chapter 10 1 side gets the positive charge and 1 side gets the bromine In whenever the bromine are usually put a hydrogen on that run on that carbon to show so I don't accidentally maker of make and structures they sold draft weekend off 3 resin structures here so we're doing terrible things were breaking error Tuesday were making further but it's not as bad as it could because we do have a resident stabilize Purwakarta here so that's helping so 3 nights present structures residents stabilized Kettering but in the last sentence ever going to regenerate the aromatic ring on you by using doing you 1 reaction and we'll do that next time I because of the great we can try to figure out what that's going to be yourself