Question

Consider the following reactions:[passage-footer]Out of the four choices (a),(b),(c), and (d), only one is correct or wrong.[/passage-footer]
Anti-addition takes place in:

Answer 1

Correct option is B. (III),(IV),(VI)
$$Reactant$$ $$Reagent \;mechanism$$ $$Product$$
a. cis (with two same groups) Syn [with two same OH groups] Meso
b. cis (with two same groups) Anti [with two same OH groups] $$(\pm)$$ or racemic
c. trans (with two same groups) Syn [with two same OH groups] $$(\pm)$$ or racemic

d. trans (with two same groups Anti [with two same OH groups] Meso

• All reactions are hydroxylation reactions. All of them are stereospecific, but if one product is formed they are regioselective. If more than one products in almost major amount are formed they are non-regioselective.
  Syn-hydroxylation occurs in ractions (I),(II), and (V); whereas $$anti-hydroxylation$$ occurs in reactions (III), (IV), and (VI).

Hence option $$(B)$$ is correct