Polymer-bound lithiumamides were used in an aldol reaction. The introduction of a spacer between the polymer backbone and the reactive site was important to enhance yields of the aldol products. The polymer-bound reagent was repeatedly used in the same reaction after the conversion to the lithium amide.
Cross-linked polymer-bound lithium dialkylamides were employed in crossed aldol reaction of various carbonyl compounds with aldehydes to afford the corresponding beta-hydroxycarbonyl compounds. The introduction of spacer chains to the polymer-bound lithium dialkylamide between the base moiety and the polystyrene backbone effectively enhanced yields of the desired aldol adducts. Sometimes better yields were obtained by using the polymer-bound reagent having an appropriate spacer-chain with those obtained using lithium diisopropylamide under homogeneous conditions. Repeated use of these polymeric reagents was demonstrated with no loss of efficiency. (C) 2004 Elsevier Ltd. All rights reserved.
Engineered Artificial Carboligases Facilitate Regioselective Preparation of Enantioenriched Aldol Adducts
作者:Duncan S. Macdonald、Xavier Garrabou、Cindy Klaus、Rebecca Verez、Takahiro Mori、Donald Hilvert
DOI:10.1021/jacs.0c02351
日期:2020.6.10
the binding and activation of specific aldol donors, as well as their subsequent reaction with diverse aldehyde acceptors. Broadening the substratescope of this evolutionarily naïve catalyst proved much easier than previous attempts to redesign natural aldolases, suggesting that such proteins may be excellent starting points for the development of customized biocatalysts for diverse practical applications