For 2,3-dibromobutane, CH3-CHBr-CHBr-CH3, which statements are correct?

(2R,3R) and (2S,3S) are enantiomers.

(2R,3S) and (2S,3S) are diastereomers.

(2R,3S) and (2S,3R) describe the same compound.

(2R,3R) and (2R,3S) are enantiomers.

(2R,3R) and (2S,3S) are enantiomers.

(2R,3S) and (2S,3S) are diastereomers.

(2R,3S) and (2S,3R) describe the same compound.

JEE Main levelOne or more correct optionsDifficulty 2 of 3st030

For 2,3-dibromobutane, $CH X_{3} - CHBr - CHBr - CH X_{3}$ , which statements are correct?

The molecule has a symmetric constitution, so there are three stereoisomers: the chiral pair

(2 R, 3 R) / (2 S, 3 S)

and the achiral meso form, written

(2 R, 3 S)

or equally

(2 S, 3 R)

. So A and B are correct.

(2 R, 3 R)

and

(2 R, 3 S)

are stereoisomers that are not mirror images (diastereomers), so C is wrong.

(2 S, 3 S)

and the meso form are likewise diastereomers: D is correct.