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A free ligand for the asymmetric dihydroxylation of olefins utilizing one-phase catalysis and two-phase separation

✍ Scribed by Yong-Qing Kuang; Sheng-Yong Zhang; Ru Jiang; Ling-Ling Wei

Book ID: 104251042
Publisher: Elsevier Science
Year: 2002
Tongue: French
Weight: 81 KB
Volume: 43
Category: Article
ISSN: 0040-4039
DOI: 10.1016/s0040-4039(02)00624-x

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✦ Synopsis

A free cinchona alkaloid derivative, which can be recovered and reused in the same way as the reported soluble polymer-supported cinchona alkaloid-derived ligands, was applied to the homogeneous asymmetric dihydroxylation of olefins. The molar ratio of ligand/olefin was 5%, being much lower than that required for the corresponding soluble polymer-supported ligands (10-25%). Yields of 82-93% and ees of 89-99% have been obtained.

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