Synthesis of organometallic pincer-supported cobalt(II) complexes

The synthesis and characterization of the new pincer-supported Co-II organometallic complexes ((PNP)-P-iPr)Co-II(Me) and ((PNP)-P-iPr)Co-II(Ph) ((PNP)-P-iPr = N{CH2CH2(P(Pr-i)(2))}2(-)) is reported. These complexes were prepared through the treatment of ((PNP)-P-iPr)Co-II(Cl) with MeMgCl or PhMgBr, respectively. Additionally, the kappa(2)-BH4 species ((PNP)-P-iPr)Co-II(kappa(2)-BH4) was synthesized through the reaction of ((PNP)-P-iPr)Co-II(Cl) with nBu(4)NBH(4). The related Co-I complex ((PNP)-P-iPr)Co-I(2,6-xylyl isonitrile) was prepared through the reaction of the known complex ((PNP)-P-iPr)Co-I(N-2) with 2,6-xylyl isonitrile. The stoichiometric and catalytic activity of the new Co-I and Co-II complexes with CO2 and formic acid was evaluated. (C) 2019 Elsevier Ltd. All rights reserved.