How can I draw a perspective formula for ( R )-1,2-dibromobutane?

1 Answer
Jul 26, 2015

Here's the method I would use.

Explanation:

Step 1. Draw the butane chain.

Butane chain

Step 2. Add wedges and dashes to #"C-1"# and #"C-2"#.

Wedge-dash

Step 3. Add the #"Br"# to the solid bond and #"H"# atoms to the other bonds of #"C-1"#.

1-bromo

Step 4. Arbitrarily add the second #"Br"# to the wedge on #"C-2"# and #"H"# to the dash (I have a 50:50 chance of getting it right).

1,2-dibromobutane

Step 5. Assign stereochemistry to #"C-2"#.

This is the #S# structure. I got it wrong!

The correct structure must be

Correct