The reaction of alkylidenephosphoranes with acyl chlorides proceeds by transylidation. Starting from an alkylidenephosphorane containing an chiral P-atom and an optical active acyl chloride, partial kinetic resolution of the organophosphorus compound is observed. The reaction of 1-carboethoxyethylidenenaphthylphenylmethylphosphorane with an optical active acyl chloride proceeds by simultaneous kinetic
Reactions of Grignard reagents from 1-halogenoallenes. Allenes—XXXIII
作者:P.M. Greaves、S.R. Landor、M.M. Lwanga
DOI:10.1016/0040-4020(75)80150-5
日期:1975.1
Grignardreagents have been prepared from 1-bromo-3,3-dialkylallenes in ether or tetrahydrofuran. The allenic acids, 4,4-dialkylbuta-2,3-dienoic acids together with 4,4-dialkylbut-2-ynoic acids are formed with carbon dioxide to the exclusion of acids with a terminal acetylene group. Two coupled products, 3,4-diethyl-3,4-dimethylhexa-1,5-diyne and 3-ethyl-3,6-dimethylocta-4,5-dien-1-yne, which are formed
From allene to allene: a palladium-catalyzed approach to β-allenyl butenolides and their application to the synthesis of polysubstituted benzene derivatives
作者:Shengming Ma、Zhenhua Gu、Youqian Deng
DOI:10.1039/b513371h
日期:——
carbonates catalyzed by Pd(OAc)2-TFP has been developed; the products were applied successfully to the Diels-Alder reaction with electron-deficient alkynes to afford polysubstitutedbenzenederivatives with an excellent regioselectivity.
Copper-Catalyzed Cyclic Oxytrifluoromethylation of 2,3-Allenoic Acids to Trifluoromethylated Butenolides
作者:Qiong Yu、Shengming Ma
DOI:10.1002/chem.201302169
日期:2013.9.27
Rounding up: An efficient copper‐catalyzed cyclicoxytrifluoromethylation of 2,3‐allenoic acids under mild conditions, providing a straightforward approach to β‐trifluoromethylatedbutenolides has been developed. Based on the successful trapping of a CF3 radical intermediate, a mechanism involving π‐allylic copper(III) or radical intermediate is proposed.
Copper(II)-Catalyzed Reaction of 2,3-Allenoic Acids, Sulfur Dioxide, and Aryldiazonium Tetrafluoroborates: Route to 4-Sulfonylated Furan-2(5<i>H</i>)-ones
作者:Kaida Zhou、Jun Zhang、Guanyinsheng Qiu、Jie Wu
DOI:10.1021/acs.orglett.8b03718
日期:2019.1.4
A copper(II)-catalyzed three-component reaction of 2,3-allenoic acids, sulfur dioxide, and aryldiazonium tetrafluoroborates under mild conditions is developed, leading to 4-sulfonylated furan-2(5H)-ones in good yields. Not only sodium metabisulfite but also 1,4-diazabicyclo[2.2.2]octane-sulfur dioxide (DABCO·(SO2)2) is workable under the conditions. This transformation proceeds through a radical process