MHT CET202620 April 2026Morning ShiftChemistryHaloalkanes and HaloarenesActual
Which among the following is NOT a feature of SN ^2 mechanism ?
Options
- ASingle step mechanism
- BBackside attack of nucleophile
- CFormation of planar carbocation intermediate
- DInvolves simultaneous bond breaking and bond forming
Correct answer
C. Formation of planar carbocation intermediate
Step-by-step solution
The S_N2 mechanism is a single-step concerted reaction where bond breaking and bond forming occur simultaneously. It involves the backside attack of the nucleophile on the substrate, leading to the inversion of configuration. The reaction proceeds via a transition state and does not involve the formation of any intermediate. The formation of a planar carbocation intermediate is a characteristic feature of the S_N1 mechanism, not the S_N2 mechanism. Answer: Formation of planar carbocation intermediate