Selective C-C bonds formation, N-alkylation and benzo[d]imidazoles synthesis by a recyclable zinc composite
作者:Guanxin Zhu、Zheng-Chao Duan、Haiyan Zhu、Dongdong Ye、Dawei Wang
DOI:10.1016/j.cclet.2021.06.060
日期:2022.1
reaction, dehydrogenation and heterocycles synthesis, instead of noble metals. The uniformly dispersed zinc composites were designed, synthesized and carefully characterized by means of XPS, EDS, TEM and XRD. The resulting zinc composite showed good catalytic activity for the N-alkylation of amines with amines, ketones with alcohols in water under base-free conditions, while unsaturated carbonyl compounds
Iridium and copper supported on silicon dioxide as chemoselective catalysts for dehydrogenation and borrowing hydrogen reactions
作者:Guanxin Zhu、Zheng-Chao Duan、Haiyan Zhu、Minghui Qi、Dawei Wang
DOI:10.1016/j.mcat.2021.111516
日期:2021.4
benzotriazole-pyridinyl-silane ligand (BPS) was designed, and the corresponding iridium and copper catalysts were synthesized and thoroughly characterized by means of EDS, TEM, and XPS. The resulting iridium composite revealed excellent catalytic activity for the reaction of tert-butanesulfinamide with benzyl alcohols, while copper catalyst could realize the synthesis of unsaturated carbonyl compounds through
one-pot, two-step process was disclosed for production of chiral α,β-epoxy ketonesfrom benzaldehydes and acetophenones catalyzed by imidazolium-modified poly(l-leucine). Two effective reaction systems with complementary high enantioselectivities (up to 98% ee) or satisfactory yields (up to 89%) have been developed. Importantly, the poly(aminoacid) catalyst can be easily recovered and recycled for ten
An Asymmetric Organocatalysis Approach to the Prenylated Alkaloid Family
作者:Matthew Rees、Nigel S. Simpkins、Louise Male
DOI:10.1021/acs.orglett.7b00193
日期:2017.3.17
Michael addition of a proline-derived triketopiperazine (TKP) to β-substituted enones and acrylamides, mediated by a cinchona alkaloid catalyst, delivers products possessing a bicyclo[2.2.2]diazaoctane structure in high yield and enantiomeric ratio (er). Further modification of the amide products toward polycyclic scaffolds resembling members of the prenylated alkaloid family is also demonstrated.
Brønsted Acid Enhanced Rhodium-Catalyzed Conjugate Addition of Aryl CH Bonds to α,β-Unsaturated Ketones under Mild Conditions
作者:Lei Yang、Bo Qian、Hanmin Huang
DOI:10.1002/chem.201201348
日期:2012.7.27
With a Brønsted acid as the solvent, the rhodium‐catalyzed direct addition of arylCH bonds to α,β‐unsaturated ketones was realized undermild reaction conditions (see scheme). The acid may assist by interceding in the conflict of the two proton‐transfer events and averting the substrate inhibition involved in this type of CH addition reaction.