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OChem... help again :-/
- Thread starter JustwantDDS
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First, CH3 group is not a leaving group so it can't be displaced. Only the chloride can leave.
Even if CH3 could leave, there would be more steric hindrance than on the other end. CH3 is a larger group than Cl. So it would still react this way. (But it's a moot point since CH3 is not LG.)
Even if CH3 could leave, there would be more steric hindrance than on the other end. CH3 is a larger group than Cl. So it would still react this way. (But it's a moot point since CH3 is not LG.)
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yeah i know Cl leaves...but rearrangement? or is that not possible at all with Eliminations?
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E2 is a concerted reaction thus it does not go rearrangements. It still prefers forming a double bond towards more substituted side unless there is a bulky base present
E1 = rearrangement
E2 = no rearrangement
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wouldn't this be an E1 reaction?
my understanding was, was that a reaction would undergo E2 with a bulky nucleophile, or with an alkoxide (given that the leaving group is on a tertiary or secondary carbon)
also, was there heat involved?
my understanding was, was that a reaction would undergo E2 with a bulky nucleophile, or with an alkoxide (given that the leaving group is on a tertiary or secondary carbon)
also, was there heat involved?
No the OP is right. He showed the Cl leaving. The problem with the reagents is though that you are using a very strong base in this case, NaOH. Once chlorine decides to leave, OH sees its moment of opportunity and attacks one of the hydrides before the molecule would have time for rearrangement. Usually with strong bases you see E2 without the formation of a carbocation. You would want to use a weaker base to go through with E1. Hopefully that clears it up for you.
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Thanks! So E2 doesnt really rearrange because of the base strength....right?
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Rearrangement can only happen because a carbocation is formed.
In E2 reaction, since the reaction is concerted the carbocation never forms.
If it is a strong base, E2/ will happen. A strong base AND a strong nucleophile will do E2 and SN2 (favors one or the other depending on the electrophile)
E1 generally doesn't happen often. It is usually a side-product of SN1 reaction.
Maybe with a weak base/nucleophile and a tertiary carbon with heat.
In E2 reaction, since the reaction is concerted the carbocation never forms.
If it is a strong base, E2/ will happen. A strong base AND a strong nucleophile will do E2 and SN2 (favors one or the other depending on the electrophile)
E1 generally doesn't happen often. It is usually a side-product of SN1 reaction.
Maybe with a weak base/nucleophile and a tertiary carbon with heat.
