1-Ethylcyclohexene is treated with $BH X_{3} \cdot THF$ and then $H X_{2} O X_{2} / NaOH$ . How many distinct stereoisomers of the alcohol product are formed in significant amount? Count enantiomers separately; the product has two stereocentres.

Numerical answer type, tolerance 0.5.

Answer: 2

The product is 2-ethylcyclohexan-1-ol. Syn addition of H and B gives only one relative configuration (trans-OH and ethyl). The planar alkene is attacked on both faces equally, so the one diastereomer forms as two enantiomers. The count is 2, not 4.

Practice Organic Reaction Mechanisms II: Electrophilic and Radical Reactions More on Hydroboration, oxymercuration, halohydrin formation

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1-Ethylcyclohexene is treated with BHX3​⋅THF and then HX2​OX2​/NaOH. How many distinct stereoisomers of the alcohol product are formed in significant amount? Count enantiomers separately; the product has two stereocentres.

Answer: 2

More questions on Hydroboration, oxymercuration, halohydrin formation

1-Ethylcyclohexene is treated with $BH X_{3} \cdot THF$ and then $H X_{2} O X_{2} / NaOH$ . How many distinct stereoisomers of the alcohol product are formed in significant amount? Count enantiomers separately; the product has two stereocentres.