The ketone shown (drawn without stereochemistry, so every product configuration is allowed) is reduced with $NaBH X_{4}$ and then protonated. Counting all configurational isomers (geometrical and optical together) of the constitution of the alcohol obtained, how many stereoisomers does it have? Give the answer as an integer.

Numerical answer type, tolerance 0.5.

Answer: 8

The ketone is 3,4-dimethylcyclohexanone (numbered from the carbonyl). Reduction gives 3,4-dimethylcyclohexan-1-ol, with stereocentres at C1, C3 and C4. The ring is not symmetric, so there are no meso forms and the count is

2^{3} = 8

(checked by stereo-enumeration).

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Answer: 8

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