presented that gives direct access to 1,1-disubstitutedtetrahydroisoquinolines. The reaction is a titanium(III)-catalyzed reductive umpolung process in which nitriles act as effective acylation agents. The method is highly chemo- and regioselective and is demonstrated in 20 examples. It is well-suited for the large-scale synthesis of functionalized tetrahydroisoquinoline products, which is exemplified in
Electron-rich triarylphosphines as nucleophilic catalysts for oxa-Michael reactions
作者:Susanne M Fischer、Simon Renner、A Daniel Boese、Christian Slugovc
DOI:10.3762/bjoc.17.117
日期:——
and intermediate Michaelacceptors such as acrylamide and acrylonitrile and for converting less acidic alcohols like isopropanol. With stronger Michaelacceptors and more acidic alcohols, the impact of the more electron-rich catalysts is less pronounced. The experimental activity trend was rationalized by calculating the Michaelacceptor affinities of all phosphine–Michael acceptor combinations. Besides
The Cobalt Carbonyl-catalyzed Hydroesterification of 3-(β-Cyano-ethoxy)propene with Carbon Monoxide and Methanol
作者:Akio Matsuda
DOI:10.1246/bcsj.42.2596
日期:1969.9
The cobalt carbonyl-catalyzed hydroesterification of 3-(β-cyanoethoxy)propene with carbonmonoxide and methanol occurred in the presence of a small amount of hydrogen at a moderate temperature, methyl 4-(β-cyanoethoxy)butyrate being produced in a much larger amount than methyl 2-methyl-3-(β-cyanoethoxy)propionate. The double-bond isomerization leading to the formation of propionaldehyde dimethylacetal
An Enantioselective Cross-Dehydrogenative Coupling Catalysis Approach to Substituted Tetrahydropyrans
作者:Ansoo Lee、Rick C. Betori、Erika A. Crane、Karl A. Scheidt
DOI:10.1021/jacs.8b03063
日期:2018.5.23
An enantioselective cross-dehydrogenative coupling (CDC) reaction to access tetrahydropyrans has been developed. This process combines in situ Lewis acid activation of a nucleophile in concert with the oxidative formation of a transient oxocarbenium electrophile, leading to a productive and highly enantioselective CDC. These advances represent one of the first successful applications of CDC for the
An approach to hyperolactone C and analogues using late stage conjugate addition on an oxonium ylide-derived spirofuranone
作者:David M. Hodgson、Elena Moreno-Clavijo、Sophie E. Day、Stanislav Man
DOI:10.1039/c3ob41251b
日期:——
A stereocontrolled synthesis of norphenyl hyperolactoneC together with its utility as a direct precursor to the anti-HIV agent hyperolactoneC and analogues by addition of organolithiums, are described. Preliminary studies to access this key building block in a catalytic enantioselective manner are also reported.