An efficient cyclo-codimerization between 1,3-diene and non-activatedterminal acetylene has been attained by the catalysis of [Rh(COD)(DPPB)]PF6 to give 1,4-disubstituted cyclohexa-1,3-dienes under mild conditions.
Isotope effects and the distinction between synchronous, asynchronous, and stepwise Diels–Alder reactions
作者:Daniel A. Singleton、Brian E. Schulmeier、Chao Hang、Allen A. Thomas、Shun-Wang Leung、Steven R. Merrigan
DOI:10.1016/s0040-4020(01)00354-4
日期:2001.6
variety of symmetrical or nearly symmetrical Diels–Alder reactions are studied by a combination of experimental isotope effects, theoretical calculations, and rate observations. Becke3LYP calculations predicted highly asynchronous transition structures for Diels–Alder reactions of bis(boryl)acetylenes, dialkyl acetylenedicarboxylates, triazolinediones, and dialkyl maleates. Rate observations and kinetic
In situ formation of alkenyl- and alkynylboranes for Diels—Alder reactions by boron—silicon exchange with alkenyl- and alkynylsilanes
作者:Daniel A. Singleton、Shun-Wang Leung
DOI:10.1016/s0022-328x(97)00001-6
日期:1997.10
A variety of alkenylsilanes underwent transmetallation with BBr3 to afford the corresponding alkenyldibromoboranes in solution. Similarly, the transmetallation of alkynylsilanes with BCl3 afforded alkynyldichloroboranes. A number of the alkenyl- and alkynylboranes are novel and useful Diels-Alder dienophiles. An ionic mechanism for the transmetallation is proposed. (C) 1997 Elsevier Science S.A.
The Chemistry of 1,3,5-Hexatriene
作者:G. F. Woods、N. C. Bolgiano、D. E. Duggan
DOI:10.1021/ja01612a023
日期:1955.4
Phenylcyclohexadienes
作者:Patrick J. Grisdale、Thomas H. Regan、J. C. Doty、John Figueras、Jack L. R. Williams