An iridium-catalyzed annulation of chalcones with sulfonylazides via cascade C–H amidation and intramolecular aza-Michael addition was developed, affording a variety of 2-aryl-2,3-dihydro-4-quinolones in moderate to good yields. This reaction features easy operation, readily available starting materials, and the cascade formation of two C–N bonds in one pot.
Cascade Reaction by Chemo- and Biocatalytic Approaches to Obtain Chiral Hydroxy Ketones and <i>anti</i>
1,3-Diols
作者:Raffaella Gandolfi、Giorgio Facchetti、Michael S. Christodoulou、Marco Fusè、Fiorella Meneghetti、Isabella Rimoldi
DOI:10.1002/open.201800056
日期:2018.5
biocatalytic cascade approach was applied for the stereoselectivesynthesis of hydroxy ketones and the corresponding 1,3‐diols. A new class of tridentate N,N,O ligands was used with copper(II) complexes for the asymmetric β‐borylation of α,β‐unsaturated compounds. The complex containing ligand L5 emerged as the best performer, and it gave the organoborane derivatives with good ee values. The corresponding keto–alcohol
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
Reaction condition controlled nickel(<scp>ii</scp>)-catalyzed C–C cross-coupling of alcohols
作者:Meng-Juan Zhang、Hong-Xi Li、David J. Young、Hai-Yan Li、Jian-Ping Lang
DOI:10.1039/c9ob00418a
日期:——
methodology employing a Ni(II) 4,6-dimethylpyrimidine-2-thiolate cluster catalyst under different reaction conditions. This catalyst could tolerate a wide range of substrates and exhibited a high activity for the annulation reaction of secondary alcohols with 2-aminobenzyl alcohols to yield quinolines. This work is an example of precise chemoselectivity control by careful choice of reaction conditions.
The effects of solvent on switchable stereoselectivity: copper-catalyzed asymmetric conjugate additions using D2-symmetric biphenyl phosphoramidite ligands
A highly enantioselective copper-catalyzed conjugateaddition of diethylzinc to acyclic aromatic enones was developed with phosphoramidite ligands bearing a D2-symmetric biphenyl backbone. This type of reaction demonstrated that toluene and THF solvents can completely reverse the absolute configuration of the products, thus simplifying the process of accessing either enantiomer (S: 92% ee, 94% yield;