An Enantioselective Iodolactonization/Cross-Coupling Protocol for the Synthesis of Highly Substituted Enol Lactones
作者:Christoph Fricke、Michael Wilking、Constantin G. Daniliuc、Ulrich Hennecke
DOI:10.1002/ejoc.201800642
日期:2018.6.29
A sequence of catalytic enantioselectiveiodolactonization followed by Palladium‐catalyzed cross‐coupling provides rapid access to highly substituted enol lactones. With DHQD2PHAL as catalyst, moderate to very good enantioselectivities in the iodolactonization step can be obtained.
Borderline metal catalysts, Bi(OTf)3 and Fe(OTf)3, were proven to work as dual activators for alkynes and N,O-acetals via σ,π-chelation, which achieved a new carboarylation reaction of alkynylarenes with N,O-acetals.
Substituted acetate compounds represented by the formula ##STR1## which are useful as pesticides and pesticidal composition containing the substituted acetate compounds as active ingredients, as well as processes for preparing the compounds and the compositions are disclosed.
Stereoselective Ir(iii)-catalyzed dimerization reaction of enynes: an entry to functionalized polyunsaturated and cyclic systems
作者:Mehdi Ez-Zoubir、Florent Le Boucher d'Herouville、Jack A. Brown、Virginie Ratovelomanana-Vidal、Véronique Michelet
DOI:10.1039/c0cc00721h
日期:——
The Ir(III) complex [Ir2H2I3((rac)-Binap)2]+I− efficiently promotes the selective dimerization of 1,6-, 1,7-enynes and functionalized alkynes. This catalytic process results in the formation of head-to-head isomers with (E)-stereoselectivity. Subsequent Rh-catalyzed cycloisomerization under reductive conditions led to the corresponding 1,2-dialkylidenecyclopentane derivatives.
Catalytic reductive desymmetrization of malonic esters
作者:Pengwei Xu、Zhongxing Huang
DOI:10.1038/s41557-021-00715-0
日期:2021.7
carbons with a pair of enantiotopic functional groups is a practical strategy for the synthesis of quaternary stereocentres, as it divides the tasks of enantioselection and C−C bond formation. The use of disubstituted malonic esters as the substrate of desymmetrization is particularly attractive, given their easy and modular preparation, as well as the high synthetic values of the chiral monoester products