Monomeric nickel hydroxide stabilized by a sterically demanding phosphorus-nitrogen PN3P-pincer ligand: synthesis, reactivity and catalysisElectronic supplementary information (ESI) available: NMR and FTIR spectra. CCDC 1817531, 1817541, 1817542, 1817545, 1817553 and 1834798. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c8dt03403f

A terminal nickel hydroxide complex (PN 3 P)Ni(OH) ( 3 ) bearing the 2 nd generation phosphorus-nitrogen PN 3 P-pincer ligand has been synthesized and structurally characterized. As a nucleophile, 3 reacts with CO to afford the hydroxycarbonyl complex 4 , (PN 3 P)Ni(COOH). 3 can also activate CO 2 and CS 2 to produce nickel bicarbonate (PN 3 P)Ni(OCOOH) ( 5 ) and bimetallic dithiocarbonate [(PN 3 P)NiS] 2 CO ( 6 ) respectively, as well as to promote aryl isocyanate and isothiocyanate insertion into the Ni-OH bond to give the corresponding (PN 3 P)NiEC(O)NHAr complexes (E = O, 7 ; E = S, 8 ). In addition, 3 catalyzes the nitrile hydration to various amides with well-defined intermediates (PN 3 P)Ni-NHC(O)R (R = Me, 9 ; R = Ph, 10 ). Various new nickel complexes and amides are synthesized using monomeric nickel hydroxide (PN 3 P)Ni(OH) ( 3 ) as the precursor or catalyst.