Scalable Negishi Coupling between Organozinc Compounds and (Hetero)Aryl Bromides under Aerobic Conditions when using Bulk Water or Deep Eutectic Solvents with no Additional Ligands. Issue 19 (6th April 2021)

• Record Type: Journal Article
• Authors: Dilauro, Giuseppe; Azzollini, Claudia S.; Vitale, Paola; Salomone, Antonio; Perna, Filippo M.; Capriati, Vito
• Is Part Of: Angewandte Chemie international edition. Volume 60:Issue 19(2021)
• Page Start: 10632
• Page End: 10636
• Publication Date: 2021-04-06
• Subjects: cross-coupling reactions -- deep eutectic solvents -- heterogeneous catalysis -- organozinc compounds -- water chemistry; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.202101571
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Pd‐catalyzed Negishi cross‐coupling reactions between organozinc compounds and (hetero)aryl bromides have been reported when using bulk water as the reaction medium in the presence of NaCl or the biodegradable choline chloride/urea eutectic mixture. Both C(sp 3 )‐C(sp 2 ) and C(sp 2 )‐C(sp 2 ) couplings have been found to proceed smoothly, with high chemoselectivity, under mild conditions (room temperature or 60 °C) in air, and in competition with protonolysis. Additional benefits include very short reaction times (20 s), good to excellent yields (up to 98 %), wide substrate scope, and the tolerance of a variety of functional groups. The proposed novel protocol is scalable, and the practicability of the method is further highlighted by an easy recycling of both the catalyst and the eutectic mixture or water. Abstract : Coupling runs across water and DES: Scalable Pd‐catalyzed Negishi cross‐couplings between (hetero)aryl bromides and organozinc halides have been developed either by using bulk water, or the choline chloride/urea eutectic mixture as a reaction medium. These processes proceed under mild conditions, short reaction times in air, in the absence of additional ligands, with high chemoselectivity and a broad substrate scope.