Abstract
The synthesis of optically active β-benzyl-γ-butyrolactones from butynediol via four transition metal catalysed reactions is reported. Key reactions are the hitherto unknown enantioselective hydrogenation of 2-benzyl-2-buten-1,4-diols using Ir(I)-phosphinooxazoline catalysts and the regiocontrolled oxidation of the resulting 2-benzyl-1,4-butanediols to the β-substituted butyro-lactones.
Key words
(+)-β-benzyl γ-butyrolactones - butynediol - enantioselective hydrogenation
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2 Current address: The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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