Nickel Nanoparticle Catalyzed Mono- and Di-Reductions ofgem-Dibromocyclopropanes Under Mild, Aqueous Micellar Conditions

• Published in: Angewandte Chemie International Edition Vol. 59; no. 40; pp. 17587 - 17593
• Main Authors: Wood, Alex B., Cortes-Clerget, Margery, Kincaid, Joseph R. A., Akkachairin, Bhornrawin, Singhania, Vani, Gallou, Fabrice, Lipshutz, Bruce H.
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 28.09.2020
• Subjects: Chemistry; Chemistry, Multidisciplinary; Physical Sciences; Science & Technology; nickel; nanoparticles; reductions; DEHALOGENATION; CYCLOPROPANATION; CHEMISTRY; COUPLINGS; ADDUCTS; micelles; water chemistry; ALKYL-HALIDES; WATER
• DOI: 10.1002/anie.202006162
• ISSN: 1433-7851

Mild mono- and di-hydrodehalogenative reductions of gem-dibromocyclopropanes are described, providing an easy and green approach towards the synthesis of cyclopropanes. The methodology utilizes 0.5-5 mol % TMPhen-nickel as the catalyst, which, when activated with a hydride source such as sodium borohydride, cleanly and selectively dehalogenates dibromocyclopropanes. Double reduction proceeds in a single operation at temperatures between 20-45 degrees C and at atmospheric pressure in an aqueous designer surfactant medium. At lower loading and either in the absence of ligand or in the presence of 2,2 '-bipyridine, this new technology can also be used to gain access to not only monobrominated cyclopropanes, interesting building blocks for further use in synthesis, but also mono- or di-deuterated analogues. Taken together, this base-metal-catalyzed process provides access to cyclopropyl-containing products and is achieved under environmentally responsible conditions.