Investigation of Nitrile Hydration Chemistry by Two Transition Metal Hydroxide Complexes: Mn–OH and Ni–OH Nitrile Insertion Chemistry

• Published in: Organometallics 2018-12, Vol.37 (24), p.4675-4684
• Main Authors: Anderson, Nickolas H, Boncella, James M, Tondreau, Aaron M
• Format: Article
• Language: English
• Subjects: INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
• ISSN: 0276-7333; 1520-6041
• DOI: 10.1021/acs.organomet.8b00687

Herein we describe the synthesis of a series of nickel complexes, including the formation of [( iPrPNHP)­Ni­(PMe3)]­[BPh4] ( iPrPNHP = HN­(CH2CH2(PiPr2))2). The ability of this phosphine complex to perform the 1,2-addition of H2O to produce the Ni–OH species [( iPrPNHP)­NiOH]­[BPh4] has been investigated. The nucleophilicity of the hydroxide moiety of both [( iPrPNHP)­NiOH]­[BPh4] and the previously reported ( iPrPNHP)­MnOH­(CO)2 was investigated through the hydration of aryl and alkyl nitriles, leading to the formation of a number of metal carboxamide (RC­(O)­NH–) bonds. This reactivity generated complexes with the general structures of [( iPrPNHP)­Ni­(NHC­(O)­R)]­[BPh4] for nickel and ( iPrPNHP)­Mn­(NHC­(O)­R)­(CO)2 for manganese. Under catalytic conditions, the hydration of nitriles using nickel complexes yielded only a single turnover. However, ( iPrPNHP)­MnOH­(CO)2 produced several turnovers, and the reaction conditions were probed for optimization.