The catalytic activity of a series of nickel complexes with different phosphinite/thiophosphinite ligands for electrocatalytic proton reduction strongly depends on the nature of the pincer ligands.

The reaction of 1,3‐dimercaptobenzene with iPr2PCl in the presence of the base NaH, furnishes the symmetric ligand [C6H4‐1,3‐(SPiPr2)2] (1a). The direct reaction of this ligand as well as of the literature‐known nonsymmetric ligand [C6H4‐1‐(SPiPr2)‐3‐(OPiPr2)] (1b) with NiCl2 affords the symmetric bis(thiophosphinito) PSCSP pincer complex [{C6H3‐2,6‐(SPiPr2)2}NiCl] (2a) as well as the phosphinito–thiophosphinito POCSP pincer complex [{C6H3‐2‐(SPiPr2)‐6‐(OPiPr2)}NiCl] (2b). Both complexes were fully characterised and their catalytic performance in Kumada coupling of aryl halides and p‐tolylmagnesium bromide under mild conditions was evaluated.

The bis(thiophosphinite) pincer complexes [(RPSCSPR)Rh(py)(H)(Cl)] (RPSCSPR = C6H4-2,6-(SPR2)2 with R = iPr, 2a and R = Ph, 2a) are prepared by metalation of the ligand precursor with [Rh(cod)Cl]2 in the...

Nickel(II) chloride complexes with PE 1 CE 2 P (E = O, S) pincer ligands were used as precursors for the generation of cyanomethyl complexes in order to investigate the influence of variations (O vs S) in the side arms of the ligands on reactivity and stability of such compounds. In this regard, five hitherto unknown Ni(II) compounds were synthesized and fully characterized. Reaction of the Ni(II) chloride complex [( iPr POCSP iPr )NiCl] (2-Cl) with 1 equiv of base and nitrile furnishes the cyanomethyl complex [( iPr POCSP iPr )NiCH 2 CN] (2-CM). Increase of the amount of base and nitrile results in the formation of 3-amidocrotononitrile complexes [( iPr POCOP iPr )NiNHC(CH 3 )CHCN] (1-ACN) and [( iPr POCSP iPr )NiNHC(CH 3 )CHCN] (2-ACN). In contrast, similar reactions of the bis(thiophosphinite) complex 3-Cl resulted in formation of a tetranuclear Ni cluster (4) or a dinuclear 1,3-dithiolate-bridged PSCSP complex 5 by unexpected cleavage of P−S bonds of the pincer ligand.