86761-76-4Relevant articles and documents
A Simple Nickel Catalyst Enabling an E-Selective Alkyne Semihydrogenation
Thiel, Niklas O.,Kaewmee, Benyapa,Tran Ngoc, Trung,Teichert, Johannes F.
, p. 1597 - 1603 (2020/02/05)
Stereoselective alkyne semihydrogenations are attractive approaches to alkenes, which are key building blocks for synthesis. With regards to the most atom-economic reducing agent dihydrogen (H2), only few catalysts for the challenging E-selective alkyne semihydrogenation have been disclosed, each with a unique substrate scope profile. Here, we show that a commercially available nickel catalyst facilitates the E-selective alkyne semihydrogenation of a wide variety of substituted internal alkynes. This results in a simple and broadly applicable overall protocol to stereoselectively access E-alkenes employing H2, which could serve as a general method for synthesis.
Controllable, Sequential, and Stereoselective C-H Allylic Alkylation of Alkenes
Qin, Ling,Sharique, Mohammed,Tambar, Uttam K.
, p. 17305 - 17313 (2019/11/03)
The direct conversion of C-H bonds into new C-C bonds represents a powerful approach to generate complex molecules from simple starting materials. However, a general and controllable method for the sequential conversion of a methyl group into a fully substituted carbon center remains a challenge. We report a new method for the selective and sequential replacement of three C-H bonds at the allylic position of propylene and other simple terminal alkenes with different carbon groups derived from Grignard reagents. A copper catalyst and electron-rich biaryl phosphine ligand facilitate the formation of allylic alkylation products in high branch selectivity. We also present conditions for the generation of enantioenriched allylic alkylation products in the presence of catalytic copper and a chiral phosphine ligand. With this approach, diverse and complex products with substituted carbon centers can be generated from simple and abundant feedstock chemicals.
Catalyst-controlled reverse selectivity in C-C bond formation: NHC-Cu-catalyzed α-selective allylic alkylation with organolithium reagents
Pizzolato, Stefano F.,Giannerini, Massimo,Bos, Pieter H.,Fa?anás-Mastral, Martín,Feringa, Ben L.
supporting information, p. 8142 - 8145 (2015/05/20)
An efficient and highly α-selective copper-catalyzed allylic alkylation of allylic halides with organolithium reagents is presented. The use of N-heterocyclic carbenes as ligands is key to reverse the common γ-selectivity of this transformation and gives rise to the corresponding linear products with high levels of regioselectivity.
