Hydroboration–oxidation reaction

[1] The process results in the syn addition of a hydrogen and a hydroxyl group where the double bond had been.

The reaction was first reported by Herbert C. Brown in the late 1950s[2] and it was recognized in his receiving the Nobel Prize in Chemistry in 1979.

This hydroboration is repeated two additional times, successively reacting each B–H bond so that three alkenes add to each BH3.

The reaction sequence is also stereospecific, giving syn addition (on the same face of the alkene): the hydroboration is syn-selective and the oxidation replaces the boron with hydroxyl having the same geometric position.

In the second step of the reaction sequence, the nucleophilic hydroperoxide anion attacks the boron atom.

N-Methylmorpholine N-oxide with catalytic tetrapropylammonium perruthenate converts the alkylborane into a carbonyl, thus a ketone or aldehyde product depending on what other groups were attached to that carbon in the original alkene.