Synthetically Useful Alkene Isomerisation and Hydroboration Reactions

Abstract

Upon treatment with a palladium catalyst and hydrogen gas in the presence of caesium carbonate, a wide range of exomethylenic allylic alcohols were found to afford their corresponding trisubstituted isomers. Although hydrogenation was an unavoidable competing pathway, careful monitoring of the reaction progress allowed the desired isomerised products to be obtained in moderate to excellent yields and high (E):(Z) ratios.

Asymmetric hydroboration reactions of a range of γ,δ-unsaturated methyl esters were found to afford their corresponding chiral 1,3-diols upon oxidation of the chiral organoborane intermediates, in a novel tandem reduction-hydroboration protocol. Alternatively, the chiral β-hydroxy ester product could be obtained by maintaining the reaction mixture at –25 °C.

Date of Award	31 Mar 2012
Original language	English
Awarding Institution	University of Bath
Supervisor	Steven Bull (Supervisor)