We report that the nucleophilic acyl substitution reaction of aliphatic and (hetero)aromaticamides by organolithium reagents proceeds quickly (20 s reaction time), efficiently, and chemoselectively with a broad substrate scope in the environmentally responsible cyclopentyl methyl ether, at ambient temperature and under air, to provide ketones in up to 93 % yield with an effective suppression of the
Preparation of Polyfunctional Organozinc Halides by an InX<sub>3</sub>- and LiCl-Catalyzed Zinc Insertion to Aryl and Heteroaryl Iodides and Bromides
作者:Andreas D. Benischke、Grégoire Le Corre、Paul Knochel
DOI:10.1002/chem.201605139
日期:2017.1.18
of zinc powder to various aryliodides in THF at 50 °C in up to 95 % yield. The use of a THF/DMPU (1:1) mixture shortens the reaction rates and allows the preparation of keto‐substituted arylzinc reagents. In the presence of In(acac)3 (3 mol %) and LiCl (150 mol %), the zinc insertion to various aryl and heteroaryl bromides proceeds smoothly (50 °C, 2–18 h). Alkyl bromides are also converted to the
functionalized diheteroaryl and diaryl ketones was developed using Ru-catalysts of minimal stereogenicity. Various ketone substrates with structurally and electronically similar groups attached to the prochiral centers were reduced successfully in good to excellent enantioselectivities and yields. This protocol provides practical and efficient access to chiral diheteroarylmethanols and benzhydrols,
Kinetically Controlled, Highly Chemoselective Acylation of Functionalized Grignard Reagents with Amides by N−C Cleavage
作者:Guangchen Li、Michal Szostak
DOI:10.1002/chem.201904678
日期:2020.1.13
(iPrMgCl⋅LiCl) permits excellent substrate scope with respect to both the amide and Grignard coupling partners. These reactions enable facile, operationally simple and chemoselective access to tetrahedral intermediates from amides under significantly milderconditions than chelation-controlled intermediates. This novel direct two-component coupling sets the stage for using amides as acylating reagents
Compounds of formula (I) which are optionally substituted 2-(&ohgr;,&ohgr;-diarylalkyl)-4,5-dihydro-1H-imidazoles and 2-(&ohgr;,&ohgr;-diarylalkyl)-1,4,5,6-tetrahydropyrimidines and salts thereof with inorganic and organic acids have interesting pharmacological properties. Thus, the compounds are useful in the treatment of type 2 diabetes.