Practice Assigning R & S

Assigning R & S with Two Chiral Centers
When dealing with compounds that have more than one chiral center, you should treat each chiral center separately. The compound in this example is 2-bromo-3-chlorobutane.

Assign the stereochemistry at carbon 2 first.

Rotate the compound so that the lowest priority group on carbon 2 is in the back. Determine whether the other groups are arranged in a clockwise (R) or counterclockwise (S) order.

Now assign the stereochemistry at carbon 3.

Rotate the compound so that the lowest priority group on carbon 3 is in the back. Determine whether the other groups are arranged in a clockwise (R) or counterclockwise (S) order.

Check my answer for this compound

Enantiomers   Enantiomers and Diastereomers   Optical activity   Organic

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