How many stereocentres (sp3 carbons bearing four different groups) does the compound HOCH2-CH(OH)-CH(CH3)-CH2-CHCl-CH(CH3)-CH(CH3)2 contain? Give the answer as an integer.

JEE Main levelNumerical answerDifficulty 2 of 3st028

How many stereocentres (sp3 carbons bearing four different groups) does the compound $HOCH X_{2} - CH (OH) - CH (CH X_{3}) - CH X_{2} - CHCl - CH (CH X_{3}) - CH (CH X_{3}) X_{2}$ contain? Give the answer as an integer.

Numerical answer type, tolerance 0.5.

Test each sp3 carbon for four different groups.

CH (OH)

(C2) has

H

OH

CH X_{2} OH

and the chain: yes.

CH (CH X_{3})

(C3): yes.

CHCl

(C5): yes. The next

CH (CH X_{3})

has

H

CH X_{3}

, isopropyl and the chain: yes. The

CH X_{2}

groups and the isopropyl carbon (two identical methyls) are not stereocentres. Total:

4