facile and efficient method has been developed for the construction of multisubstituted α,β-enones through the direct selective iodosulfonylation of alkylynones with sulfonylhydrazides and iodine pentoxide. The present methodology offers a simple and attractive approach to various multisubstituted α,β-enones in moderate to good yields with excellent stereo- and regioselectivities under the metal- and
Rhodium-Catalyzed Intermolecular <i>trans</i>
-Disilylation of Alkynones with Unactivated Disilanes
作者:Tao He、Li-Chuan Liu、Le Guo、Bin Li、Qing-Wei Zhang、Wei He
DOI:10.1002/anie.201804223
日期:2018.8.20
of alkynes could provide rapid entry to synthetically useful 1,2‐bissilyl‐alkenes, but is currently limited to activated disilanes reacting in an intramolecular fashion. Reported herein is an efficient rhodium(I)‐catalyzed intermolecular disilylation of a wide array of alkynones with unactivated disilanes. Importantly, this reaction produces exclusively trans‐disilylation products, selectivity that
Zinc‐Catalyzed Dehydrogenative Cross‐Coupling of Terminal Alkynes with Aldehydes: Access to Ynones
作者:Shan Tang、Li Zeng、Yichang Liu、Aiwen Lei
DOI:10.1002/anie.201509042
日期:2015.12.21
Because of the lack of redox ability, zinc has seldom been used as a catalyst in dehydrogenativecross‐coupling reactions. Herein, a novel zinc‐catalyzeddehydrogenativeC(sp2)H/C(sp)H cross‐coupling of terminal alkynes with aldehydes was developed, and provides a simple way to access ynones from readily available materials under mild reaction conditions. Good reaction selectivity can be achieved
Organocatalytic Asymmetric Michael/Dieckmann Cyclization Reaction of Alkynones To Construct Spirocyclopentene Oxindoles
作者:Jiawen Lang、Yi Li、Tengfei Kang、Xiaoming Feng、Xiaohua Liu
DOI:10.1021/acs.orglett.9b02519
日期:2019.9.6
catalysis of a chiral guanidine catalyst and NaH. This protocol provides access to a wide range of synthetically useful optically active spirocyclopentenone oxindoles and their derivatives under mild reaction conditions.
Novel Stereo‐Induction Pattern in Pudovik Addition/Phospha‐Brook Rearrangement Towards Chiral Trisubstituted Allenes
作者:Jia‐Yan Zheng、Fan Wang、Yan Zhang、Zheng Zheng、Jia‐Hong Wu、Xiaoyu Ren、Zhishan Su、Wenchuan Chen、Tianli Wang
DOI:10.1002/anie.202403707
日期:2024.5.27
developed to synthesize axially chiral phosphorus allenes through a PPS-catalyzed asymmetric Pudovik addition followed by phospha-Brook rearrangement. Mechanistic experiments have demonstrated that the enantio-determining step is the 1,2-addition, with the subsequent rearrangement undergoing a central-to-axial chirality transfer.