Question #3d213

1 Answer
Dec 15, 2016

There are 4 stereoisomers of 2-bromo-4-chloropentane.

Explanation:

The formula of 2-bromo-4-chloropentane is

#"CH"_3 stackrelcolor(blue)("*")("C")"HClCH"_2 stackrelcolor(blue)("*")("C")"HBrCH"_3#

The two chiral carbons are marked with an asterisk.

The maximum number of stereoisomers is #2^n = 2^2 = 4#.

The various possibilities are shown below.

Bromochloropentane

Compound #bb"A"# is #(2S,4R)"-2-bromo-4-chloropentane"#.

Compound #bb"B"# is #(2R,4S)"-2-bromo-4-chloropentane"#.

#bb"A"# and #bb"B"# are enantiomers (nonsuperimposable mirror images) of each other.

Compound #bb"C"# is #(2R,4R)"-2-bromo-4-chloropentane"#.

Compound #bb"D"# is #(2S,4S)"-2-bromo-4-chloropentane"#.

#bb"C"# and #bb"D"# are enantiomers of each other.