How many optically active stereomers are possible for butane-2,3-diol

Options

A. 3
B. 4
C. 1
D. 2

Answer

A

Explanation

No. of asymmetric or chiral carbon =2 , Therefore no. of optical isomers = `2^(n) = 2^(2) = 4` , No. of optically active stereomers = `4 -1 = 3`, because meso compound is optically inactive due to internal compensation.