Stereoselectivity in the Synthesis of Enol Esters from Chloromercurio Aldehydes and Acyl Chlorides
作者:Wakichi Fukuda、Hozumi Sato、Hiroshi Kakiuchi
DOI:10.1246/bcsj.59.751
日期:1986.3
Reactions of chloromercurio aldehydes with acylchlorides gave a variety of (Z)- and (E)-enol esters. The Z/E ratio of the enol esters is dependent on the structure of chloromercurio aldehydes but independent of that of acylchlorides. Z-Rich enol esters were prepared by acylation of 2-chloromercurio aldehydes derived from propanal, butanal, and 2-phenylethanal, while E-rich 1-acyloxy-1,3-butadiene
[Pd(μ-Br)(P<sup><i>t</i></sup>Bu<sub>3</sub>)]<sub>2</sub> as a Highly Active Isomerization Catalyst: Synthesis of Enol Esters from Allylic Esters
作者:Patrizia Mamone、Matthias F. Grünberg、Andreas Fromm、Bilal A. Khan、Lukas J. Gooßen
DOI:10.1021/ol301563g
日期:2012.7.20
to be highly active for catalyzing double-bond migration in various substrates such as unsaturated ethers, alcohols, amides, and arenes, under mild conditions. It efficiently mediates the conversion of allylic esters into enolesters, rather than inserting into the allylic C–O bond. The broad applicability of this reaction was demonstrated with the synthesis of 22 functionalized enolesters.
发现二聚体Pd(I)络合物[Pd(μ-Br)(P t Bu 3)] 2具有高活性,可催化不饱和醚,醇,酰胺和芳烃等各种底物中的双键迁移,在温和的条件下。它有效地调节了烯丙基酯到烯醇酯的转化,而不是插入烯丙基C–O键。通过合成22种官能化的烯醇酯证明了该反应的广泛适用性。
Polymeric compositions having inherent electroconductive properties and unsaturated electron-donor and electron-receptor polymerizable monomers for producing such compositions in the form of blends of homopolymers of such monomers or as copolymers of such monomers.
Total synthesis of acosamine and daunosamine utilizing a diastereoselective intramolecular [3+2] cycloaddition
作者:P.M. Wovkulich、M.R. Uskoković
DOI:10.1016/s0040-4020(01)96700-6
日期:1985.1
acosamine (4) has been accomplished via a diastereoselective intramolecular nitrone-olefin cyclization. In the key step the chiral nitrone 12a cyclized to give two isoxazolidines 13a and 14a in an 82:18 ratio. Further elaboration of 13a led to daunosamine and acosamine. The effects of olefin substitution on the diastereoselectivity of the cycloaddition was also examined.
Unexpected Formation of Aryl Ketones by Palladium-Catalyzed Coupling of Aryl Bromides with Vinylic Acetates
作者:Mickaël Jean、Jacques Renault、Philippe Uriac、Marc Capet、Pierre van de Weghe
DOI:10.1021/ol7015065
日期:2007.8.1
A palladium-catalyzed coupling reaction of aryl bromides with vinylic acetates in the presence of tributyltin methoxide has been described. Unexpected formation of aryl ketones was obtained. Preliminary mechanistic studies indicated that the reaction proceeded by the addition of the aryl moiety in the coordination sphere of palladium to a ketene.