Consider the following reactions :

Which of the following are stereospecific reactions ?

Options

A. `(I),(II)`
B. `(I),(II),(III)`
C. `(III),(IV),(V)`
D. All

Answer

D

Explanation

All these reaction are hydroxylation reaction. 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 reaction `(I),(II)`, and `(V)` , whereas anti-hydroxylation occurs in reactions `(III), (IV)`, and `(VI)`
`{:(,"Reactant",underset("mechanism")("Reagent"),"Product",),("a".,underset("same groups)")("cis(with two"),underset("same OH groups]")"syn [with two","Meso",),("b".,underset("same groups)")"cis (with two",underset("same OH groups]")("Anti (with two"),(pm)"or racemic",),("c".,underset("same groups)")("trans (with two)"),underset("same OH groups")"Syn [with two",(pm)"or racemic",),("d".,underset("same groups)")"trans (with two",underset("same OH groups]")"Anti [with two","Meso",):}`