Exploring Regioselectivity and Stereoselectivity via GC Analysis of the Product of the Hydroboration-Oxidation of 1-Methylcyclohexene

Hydroboration-Oxidation reaction is both regioselective and diastereoselective. It is regioselective because it places the alcohol at the anti-Markovnikov position, and it is diastereoselective because the reaction proceeds via syn-addition of the -H and -OH groups across the two alkene carbons. By the hydroboration/oxidation of 1-methylcyclohexene and analyzing the product using an appropriate chiral gas chromatographic method, students were able to determine the ratio of Markovnikov to anti-Markovnikov products and also calculate the ratio of trans diastereomer to cis diastereomer, thus confirming the regioselectivity and stereoselectivity of the reaction. The GC provided an additional visual experience towards understanding the concepts.