Chemistry Forum

Draw the mechanism of the reaction of (R)-2-bromooctane with NaCN in HMPA solvent.

SN₂ conditions:
good nucleophile, poor base
good leaving group
2o
alkyl halide so not too much
steric hindrance for backside
attack.
E₁ conditions:
weak base, poor nucleophile
good leaving group
polar aprotic solvent
2o
carbocation
will make most stable alkene
E₂ & SN₂ conditions favored. E₂ will be major product.
good nucleophile and strong base
good leaving group, can make products without a carbocation
steric hindrance in SN₂ rxn will make it.
SN₂ conditions:
good nucleophile, poor base
good leaving group
2o
alkyl halide so not too much
steric hindrance for backside
attack. polar protic solvent helps
solvate leaving group