The enantioselective tandemreaction of β,γ‐unsaturated α‐ketoesters with β‐alkynyl ketones was realized by a bimetallic catalytic system of achiral AuΙΙΙ salt and chiral N,N′‐dioxide‐MgΙΙ complex. The cycloisomerization of β‐alkynyl ketone and asymmetric intermolecular [4+2] cycloaddition with β,γ‐unsaturated α‐ketoesters subsequently occurred, providing an efficient and straightforward access to
Facile synthesis of substituted diaryl sulfones <i>via</i> a [3 + 3] benzannulation strategy
作者:Xiang-zheng Tang、Lang Tong、Hua-ju Liang、Jie Liang、Yong Zou、Xue-jing Zhang、Ming Yan、Albert S. C. Chan
DOI:10.1039/c8ob00662h
日期:——
base-mediated [3 + 3] benzannulation strategy for the conversion of 1,3-bis(sulfonyl)propenes and β,γ-unsaturated α-ketoesters to diaryl sulfones has been developed. This method provides facile, metal-free and efficient access to highly substituted diaryl sulfones in good to excellent yields. In addition, the sulfonyl group could be easily removed or converted to other functional groups via an organostannane
Pyrazolines and their intermediates, including all geometric and stereoisomers of the pyrazolines and intermediates, agricultural compositions containing the pyrazolines, and methods for use as insecticides.
Heterocyclic pyrazoline carboxanilide insecticides of the general formula:
including all geometric and stereoisomers thereof, as well as agricultural compositions containing them.
A chemo- and stereoselective 1,4-hydrosilylation of alpha,beta-enone esters was developed using triethylsilane and trifluoroacetic acid under indium chloride catalysis.