How can I draw all possible stereoisomers for 2-bromo-4-chlorohexane?

1 Answer
Aug 27, 2015

Answer:

Identify the chiral centres and then draw all the possibilities.

Explanation:

Step 1. Draw the bond-line structure for 2-bromo-4-chlorohexane.

Bond-Line

Step 2. Identify the chiral centres.

The chiral centres are #"C-2"# and #"C-4"#.

Step 3. Calculate the number of possible stereoisomers.

The maximum number of stereoisomers is #2^n#, where #n# is the number of chiral centres.

Here, #n=2#. and #2^2 =4#, so there are four possible stereoisomers.

Step 4. Draw the stereoisomers.

If we indicate the stereochemistry of the bonds to the heteroatoms by wedges and dashes, the structures are

Wedge-Wedge

Wedge-Dash

Dash-Wedge

Dash-Dash

Step 5. Check for meso isomers.

There is no internal plane of symmetry, so there are no meso isomers.

The above structures are all unique stereoisomers.