question_answer

How many chiral stereoisomers can be drawn for 2-bromo-3-chlorobutane?

A)  2     

B)  3     

C)  4     

D)  5

Correct Answer: C

Solution :

The structure of 2-bromo-3-chlorobutane is \[C{{H}_{3}}-\overset{*}{\mathop{\underset{\begin{smallmatrix}  | \\  Br \end{smallmatrix}}{\mathop{C}}\,}}\,H-\underset{\begin{smallmatrix}  | \\  Cl \end{smallmatrix}}{\mathop{\overset{*}{\mathop{C}}\,}}\,H-C{{H}_{3}}\] (\[{{C}^{*}}=\] asymmetric carbon atom) The number of chiral stereoisomers \[={{2}^{n}}\] (where, n = number of asymmetric carbon atoms) \[={{2}^{2}}=4\] The structure of these isomers are as