Catalytic Coupling between Unactivated Aliphatic C–H Bonds and Alkynes via a Metal–Hydride Pathway
作者:Yan Xu、Michael C. Young、Guangbin Dong
DOI:10.1021/jacs.7b02020
日期:2017.4.26
We report a Rh(I)-catalyzed site-selective coupling between ketone β-C(sp3)-H bonds and aliphatic alkynes using an in situ-installed directing group. Upon hydrogenation or hydration, various β-alkylation or β-aldol products of the ketones are obtained with broad functional group tolerance. Mechanistic investigations support the involvement of a Rh-H intermediate through oxidative addition of Rh(I)
The palladium-catalyzed denitrogenative indolization of N-aroylbenzotriazoles 1 and internal alkynes 2 produced the corresponding polysubstituted indoles 3 in good to high yields. For example, the reaction of 5,6-dimethyl-1-[4-(trifluoromethyl)benzoyl]benzotriazole (1j) with 6-dodecyne (2a), 4-octyne (2b), and diphenylacetylene (2f) in the presence of 10 mol % of Pd(PPh3)4 without solvent at 130 °C
Rhodium-Catalyzed Three-Component Reaction of Alkynes, Arylzinc Chlorides, and Iodomethanes Producing Trisubstituted/Tetrasubstituted Alkenes with/without 1,4-Migration
作者:He Meng、Shiming Bai、Yu Qiao、Ting He、Weiyi Li、Jialin Ming
DOI:10.1021/acs.orglett.2c02299
日期:2022.7.29
A three-component reaction of alkynes, arylzinc chlorides, and iodomethanes was found to proceed in the presence of a rhodium catalyst to give high yields of trisubstituted/tetrasubstituted alkenes. The usual arylzinc chlorides only gave trisubstitutedalkenes, generated through a migratory carbozincation–cross-coupling sequence, where 1,4-Rh migration from an alkenyl carbon to an aryl carbon occurred