The invention provides novel six and seven-carbon termini-differentiated polypropionate stereotetrads and stereopentads useful in syntheses of natural products. The invention also provides a novel alkylative sulfenylation-desulfonylation process that efficiently transforms enantiopure epoxyvinyl sulfones to syn and anti dienylsulfides in two operations.
Asymmetric Approach toward Chiral Cyclohex-2-enones from Anisoles via an Enantioselective Isomerization by a New Chiral Diamine Catalyst
作者:Jung Hwa Lee、Li Deng
DOI:10.1021/ja308623n
日期:2012.11.7
A 3-step asymmetricapproach toward the optically active chiral cyclohex-2-enones from anisoles has been developed. The crucial asymmetric induction step is an unprecedented catalytic enantioselective isomerization of β,γ-unsaturated cyclohex-3-en-1-ones to the corresponding α,β-unsaturated chiral enones. This new asymmetric transformation was realized by cooperative iminium-base catalysis with an
Syntheses of Highly Substituted Enantiopure C6 and C7 Enones<sup>1</sup>
作者:Jerry Evarts、Eduardo Torres、Philip L. Fuchs
DOI:10.1021/ja026760m
日期:2002.9.1
Enantiopure epoxyvinyl sulfones SS-9a, SS-9b, produced from Jacobsen epoxidation of 2-phenylsulfonyl 1,3-cyclohexa- and cycloheptadiene, are used as a template for the construction of substituted cycloalkenones and as chiral synthetic equivalents of enones a and b. The addition of carbon nucleophiles to SS-9a, SS-9b is high yielding and stereospecific. Enantiopure alpha,beta- and gamma-substituted cycloalkenones are easily constructed using a variety of methods.