Hydroboration/Oxidation of Alkynes BHa(borane)adds to alkynes to give a vinylic borane Oxidation with H2O2 produces an enol which tautomerize to the ketone or aldehyde,depending on the structure of the alkyne An internal alkyne BR H OH 3 CHCH2C=CCH2CH3 日02 C=C THF H,O.NaOH 3-Hexyne CH,CH2 CH,CH CH CH2 CH2CH3 A vinylic borane An enol 0 3 CH CH2CH2CCH2CH 3-HexanoneHydroboration/Oxidation of Alkynes „ BH 3 (borane) adds to alkynes to give a vinylic borane „ Oxidation with H 2 O 2 produces an enol which tautomerize to the ketone or aldehyde, depending on the structure of the alkyne