Synthesis of (tetrahydrofuran-2-yl)acetates based on a ‘cyclization/hydrogenation/enzymatic kinetic resolution’ strategy
摘要:
A variety of (tetrahydrofuran-2-yl)acetates and (pyrrolidin-2-yl)acetates have been prepared by hydrogenation of 2-alkylidene-tetrahydrofurans and 2-alkylidenepyrrolidines, which are readily available by cyclization reactions of 1,3-dicarbonyl dianions (free dianions') or 1,3-bis-silyl enol ethers ('masked dianions') with 1,2-dielectrophiles. The enzymatic kinetic resolution of (tetrahydrofuran-2-yl)acetates with recombinant esterase Est56 proceeded with excellent enantioselectivities (E > 100). (c) 2006 Elsevier Ltd. All rights reserved.
Steering Reaction Pathways: From Benzyl Claisen Rearrangements to Powerful Ionic Shifts
作者:Viviana Valerio、Claire Madelaine、Nuno Maulide
DOI:10.1002/chem.201003591
日期:2011.4.18
Take a walk on the wild side: A novel benzylClaisen cascade rearrangement of keteniminium salts is described. The reaction leads to α‐arylated lactones under metal‐free conditions (top scheme; Tf=trifluoromethanesulfonyl). It is further demonstrated that the cationic intermediates involved can be steered away from pericyclic reaction manifolds into powerful ionic shifts through reaction design (bottom
[EN] METHOD OF PREPARING (3R, 3aS, 6aR) -3- HYDROXYHEXAHYDROFURO [2, 3-b] FURAN AND RELATED COMPOUNDS<br/>[FR] PROCEDE DE PREPARATION DE (3R, 3AS, 6AR) -3- HYDROXYHEXAHYDROFURO [2, 3-B] FURANE ET DE COMPOSES APPARENTES
申请人:UNIV ILLINOIS
公开号:WO2004033462A2
公开(公告)日:2004-04-22
A method of synthesizing (3R, 3aS, 6aR) -3- hydroxyhexahydrofuro [2, 3-b] furan (I), and related compounds, in high yield and high enantiomeric selectivity is disclosed. Also disclosed is a method of manufacturing (5S) -5-(benzyloxymethyl) -5H-furan-2-one.