Question

Predict the order of reactivity of the following compounds in SN1 and SN2 reactions

C6H5CH2Br , C6H5CH(C6H5)Br , C6H5CH(CH3)Br , C6H5C(CH3)(C6H5)

Answer 1

in nSN1 the 3 degree halide is most reactive therefore C6H5C(CH3)(C6H5)Br is most reactive .in case of 2 degree halide the one with 2 phenyl group is more reactive due to carbocation stabilisation by resonance .the 1 degree halide is less stable .hence the order is
C6H5C(CH3)(C6H5)Br> C6H5CH(C6H5)Br>C6H5CH(CH3)Br>C6H5CH2Br