Lipase-catalyzed transesterification as a practical route to homochiral syn-1,2-diols. The synthesis of the taxol side chain
作者:Donghyun Lee、Mahn-Joo Kim
DOI:10.1016/s0040-4039(98)00147-6
日期:1998.4
syn-2,3-Dihydoxy-3-phenyl-propanoic acid methyl ester (1a) and its simple derivatives (1b-e) are efficiently resolved in LPS-catalyzed transesterification, leading to the synthesis of the taxolsidechain and analogs from both resolved enantiomers.
Osmium-Catalyzed Olefin Dihydroxylation and Aminohydroxylation in the Second Catalytic Cycle
作者:Peng Wu、Robert Hilgraf、Valery V. Fokin
DOI:10.1002/adsc.200505252
日期:2006.6
Two catalytic cycles operate in the osmium-catalyzedolefindihydroxylation and aminohydroxylation. Slow hydrolysis of the Os(VI) monoglycolate (or monoazaglycolate in aminohydroxylation) intermediate often results in the addition of another molecule of olefin thereby shunting the catalysis into the second catalytic cycle. As a result, both enantio- and chemoselectivity are reduced. A series of new