Herein we disclose an asymmetric allylation of 3-hydroxyisobenzofuran-1(3H)-ones with boron allylation reagents to construct chiral phthalide derivatives. The simple Bi(OAc)3/chiral phosphoricacid catalytic system proves to be efficient in this method, delivering the desired chiral 3-allylisobenzofuran-1(3H)-ones in good yields (up to 99%) and high enantioselectivities (up to 99.5:0.5 e.r.) under mild
Enantioselective Iridium-Catalyzed Phthalide Formation through Internal Redox Allylation of Phthalaldehydes
作者:James M. Cabrera、Johannes Tauber、Michael J. Krische
DOI:10.1002/anie.201712015
日期:2018.1.26
An inside job: Enantioselective phthalide synthesis was achieved through internal redox allylation of o‐phthalaldehydes. Oxidative esterification is balanced by reductive carbonyl addition to achieve an overall redox‐neutral process. This method enabled formal syntheses of ent‐spirolaxine methyl ether and CJ‐12,954.
An Indium-Mediated Allylative/Transesterification DFT-Directed Approach to Chiral C<sub>(3)</sub>-Functionalized Phthalides
作者:Roya Mirabdolbaghi、Travis Dudding
DOI:10.1021/ol301566f
日期:2012.7.20
A one-pot synthesis of chiral C-(3)-substituted phthalides via an indium-mediated allylation/transesterification reaction is described. The development of this reaction was facilitated through the applied use of DFT calculations to rationalize the stereoselection of a chiral In-mediated process. It was discovered that the enantiomeric excess of this reaction depended upon the steric size, chain length, and substitution of the aldehyde employed.
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.