What is the order of speed of SN1 and SN2 for the following molecules?
My idea:
For SN1 I think it is C>A>B>D
C - the carbocation has resonance
A - I believe the double bond acts as an electron donating group and helps stabilize the positive charge on the carbocation.
B - just a secondary carbocation
D - vinylic carbocation are highly unstable
For SN2 I think it is the same order C>A>B>D
C - the allyl group is completely planer and as a result it allows the nucleophile an easier approach to the alpha carbon
Honesty I'm not confident between B and A
A - while the CH2=CHCH2- group isnt planer I think the double bond allows for a more linear geometry of the group and a more condensed electron cloud which results in a smaller steric interference and an easier approach for the nucleophile.
B - all carbons in the propyl group are sp³ hybridization therefore the electron cloud is less linear and condensed resulting in a larger steric interference than compound A
D - vinylic carbons dont react in substitution since the nucleophile has to go through the plane of the electron dense double bond to attack the alpha carbon
What do you guys think is this correct?