Classify the configuration of product of a symmetric carbon atom. Consider the replacement of a group X by Y in the following reaction.
Process for A, B and A+B as under
(A) A-retention of configuration A+B racemisation, B-Invention of configuration
(B) A-Inversion of configuration, A+B retention of configuration, B-recemisation.
(C) A+B - Inversion of configuration, B-retention of config n; A-recemisation.
(D) None of them
