A Versatile Route to 2-Substituted Cyclic 1,3-Dienes via a Copper(I)-Catalyzed Cross-Coupling Reaction of Dienyl Triflates with Grignard Reagents
作者:A. Sofia E. Karlström、Magnus Rönn、Atli Thorarensen、Jan-E. Bäckvall
DOI:10.1021/jo971737i
日期:1998.4.1
A general synthesis of 2-substituted cyclic1,3-dienes in two steps from alpha,beta-unsaturated ketones has been developed. Formation of a dien-2-yl triflate followed by a copper(I)-catalyzed cross-coupling reaction with a Grignard reagent gives 2-substituted dienes in fair to excellent yields. Alkyl, aryl, and allyl Grignard reagents can be used.
Enantioselective Halocyclization Using Reagents Tailored for Chiral Anion Phase-Transfer Catalysis
作者:Yi-Ming Wang、Jeffrey Wu、Christina Hoong、Vivek Rauniyar、F. Dean Toste
DOI:10.1021/ja305795x
日期:2012.8.8
A chiral anion phase-transfer system for enantioselective halogenation is described. Highly insoluble, ionic reagents were developed as electrophilic bromine and iodine sources, and application of this system to o-anilidostyrenes afforded halogenated 4H-3,1-benzoxazines with excellent yield and enantioselectivity.