Regiodivergent Stereoselective Access to Fused Alkylideneazetidines
作者:Arif Music、Andreas N. Baumann、Michael Eisold、Dorian Didier
DOI:10.1021/acs.joc.7b02786
日期:2018.1.19
simplification of 2H-azetine synthesis, a regiodivergent approach to fused 2- and 3-alkylideneazetines was designed via the intermediate formation of unprecedented vinylazetine structures. Concise sequences to the latter are described from which an expected unsaturated fused ring system was isolated with very high yields and regio- and stereoselectivities by [4 + 2] cycloadditions.
Direct catalytic cross-coupling of alkenyllithium compounds
作者:Valentín Hornillos、Massimo Giannerini、Carlos Vila、Martín Fañanás-Mastral、Ben L. Feringa
DOI:10.1039/c4sc03117b
日期:——
A catalytic method for the direct cross-coupling of alkenyllithium reagents with aryl and alkenylhalides is described. The use of a catalyst comprising Pd2(dba)3/XPhos allows for the stereoselective preparation of a wide variety of substituted alkenes in high yields under mild conditions. In addition (1-ethoxyvinyl)lithium can be efficiently converted into substituted vinyl ethers which, after hydrolysis
Phenyl- and vinyllithiums having an alkyl substituent at their ortho- and cis-position, respectively, readily added to alkynes in the presence of 5 mol% of Fe(acac)(3). The reaction of o-(trimethylsilyl)phenyllithium with alkynes gave benzosiloles through an addition-cyclization sequence.