A synthetic route to chiral C(3)-functionalized phthalides via a Ag(I)-catalyzed allylation/transesterification sequence
作者:Roya Mirabdolbaghi、Travis Dudding
DOI:10.1016/j.tet.2013.02.002
日期:2013.4
A Ag(I)-catalyzed synthesis of chiral C-(3)-substituted phthalides (8a-f) via a Sakurai-Hosomi allylation/transesterification reaction is described (ee <= 86%). A notable feature of this reaction is that it utilizes ortho-substituted aldehydes, which are a class of compounds that generally afford poor levels of stereoinduction when applying most known catalytic asymmetric allylation approaches. It was also found that elongation of the n-alkyl chain length (R-1, up to n=6; R-2=H) of the starting alkyl 2-formylbenzoates (7g-i) improved the enantiomeric excess (ee) of the product. Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved.