title: Preparation of Polyfunctional Organozinc Halides by an InX3- and LiCl-Catalyzed Zinc Insertion to Aryl and Heteroaryl Iodides and Bromides.
abstract: A catalytic system consisting of InCl3(3 mol %) and LiCl (30 mol %) allows a convenient preparation of polyfunctional arylzinc halides via the insertion of zinc powder to various aryl iodides 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 corresponding zinc reagents in the presence of In(acac)3(10 mol %) and LiCl (150 mol %) in 70-80 % yield.
authors.affiliation: Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, Haus F, 81377, München, Germany.
authors.forename: Andreas D
authors.initials: AD
authors.lastname: Benischke
authors.affiliation: Laboratoire de Chimie Moléculaire, CNRS, Ecole Polytechnique, Route de Saclay, 91128, Palaiseau, France.
authors.forename: Grégoire
authors.initials: G
authors.lastname: Le Corre
authors.affiliation: Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, Haus F, 81377, München, Germany.
authors.forename: Paul
authors.initials: P
authors.lastname: Knochel
keywords: cross-coupling; indium; lithium chloride; organozinc reagents; zinc