Direct synthesis of pyrroles via 1,3-dipolar cycloaddition of azomethine ylides with ynones
作者:Zheng Wang、Ying Shi、Xiaoyan Luo、De-Man Han、Wei-Ping Deng
DOI:10.1039/c3nj00067b
日期:——
A direct and facile synthesis of multi-substituted pyrroles via AgOAc-catalyzed 1,3-dipolarcycloaddition of azomethine ylides with ynones is developed, providing the corresponding adducts in moderate to high yields (up to 89%).
Electrochemically Mediated Oxidation of Sensitive Propargylic Benzylic Alcohols
作者:Chad E. Hatch、Maxwell I. Martin、Philip H. Gilmartin、Lu Xiong、Danielle J. Beam、Glenn P. A. Yap、Matthew J. Von Bargen、Joel Rosenthal、William J. Chain
DOI:10.1021/acs.orglett.1c03860
日期:2022.2.25
The electrochemicaloxidation of sensitive propargylic benzylic alcohols having varying substituents is reported. We describe the preparation and characterization of N-hydroxytetrafluorophthalimide (TFNHPI) and pseudo-high-throughput development of a green electrochemicaloxidation protocol for sensitive propargylic benzylic alcohols that employs TFNHPI as a stable electrochemical mediator. The electrochemical
Multisubstituted pyrazole synthesis via [3 + 2] cycloaddition/rearrangement/N H insertion cascade reaction of α-diazoesters and ynones
作者:Peng Zhao、Zi Zeng、Xiaoming Feng、Xiaohua Liu
DOI:10.1016/j.cclet.2020.11.053
日期:2021.1
Al(OTf)3 as the catalyst are described. A series of 4-substituted pyrazoles were obtained via [3 + 2] cycloaddition, 1,5-ester shift, 1,3-H shift, and N H insertion process. Deuteriumlabelling experiments, kinetic studies and control experiments were carried out for the rationalization of the mechanism.
Enantioselective conjugate additions of in situ generated 2-alkoxycarbonyl-3(2H)-furanones to three distinct types of π-electrophiles (terminal alkynones, α-bromo enones, and α-benzyl nitroalkenes) are reported. Catalysis by a nickel(II)–diamine complex provided alkynone-derived adducts with high enantioselectivity, preferentially as the Z-isomers, and completely suppressed the undesired O-alkylation
An efficient N,N’-dioxide-scandium(III) complex catalytic system has been developed for the asymmetric dearomatization of β-naphthols through conjugateaddition to alkynones. A variety of Z-predominated β-naphthalenone compounds were obtained in moderate to high yields with excellent enantioselectivities (up to 98% ee). Moreover, a possible transition state was proposed to explain the origin of the