Transition metal chemistry of large-bite bisphosphines, N,N-bis(diphenylphosphinobenzyl)-N-phenylamine and bis(2-diphenylphosphinobenzyl)ether

•Large bite bisphosphines containing N and O atoms in the ligand framework have been synthesized.•Cis and trans complexes of Pd(II) and Pt(II) have been isolated.•Chelating as well as bridging coordination modes have been observed.

Oxidation reactions and transition metal chemistry of large bite bisphosphines N,N-bis(diphenylphosphinobenzyl)-N-phenylamine (1) and bis(2-diphenylphosphinobenzyl)ether (2) are described. The reactions of 1 and 2 with chalcogenides in 1:2 M ratios afforded bis-chalcogenides. Reactions of 1 and 2 with M(COD)Cl2 (M = Pd, Pt) in 1:1 M ratios yielded trans-[MCl2{C6H5N(CH2-2-C6H4PPh2)2}-κ2P,P] (M = Pd, 9; Pt, 10) and cis-[MCl2{O(CH2-2-C6H4PPh2)2}-κ2P,P] (M = Pd, 11; Pt, 12), respectively. Treatment of 1 and 2 with [Pd(η3-C3H5)Cl]2 and [RuCl2(η6-p-cymene)]2 in 1:1 M ratios produced dinuclear complexes of the type [Pd2Cl2(η3-C3H5)2-μ-{C6H5N(CH2-2-C6H4PPh2)2}-μP,P] (13), [Pd2Cl2(η3-C3H5)2-μ-{O(CH2-2-C6H4PPh2)2}-μP,P] (14), [{Ru(η6-p-cymene)}2-μ-{C6H5N(CH2-2-C6H4PPh2)2}-μP,P] (17) and [{Ru(η6-p-cymene)}2-μ-{O(CH2-2-C6H4PPh2)2}-μP,P] (18). The reactions of 1 and 2 with one half equivalent of [Pd(η3-C3H5)Cl]2 followed by the addition of AgOTf yielded chelate complexes [Pd(η3-C3H5){C6H5N(CH2-2-C6H4PPh2)2}-κ2P,P]OTf (15) and [Pd(η3-C3H5){O(CH2-2-C6H4PPh2)2}-κ2P,P]OTf (16). The reactions of 1 and 2 with [AuCl(SMe2)] in 1:2 and 1:1 M ratios afforded dinuclear [(Au2Cl2)C6H5N(CH2-2-C6H4PPh2)2-μ-P,P] (19), [Au2Cl2O(CH2-2-C6H4PPh2)2-μ-P,P] (20) and mononuclear complexes [(AuCl)C6H5N(CH2-2-C6H4PPh2)2-κ2P,P] (21), [(AuCl)O(CH2-2-C6H4PPh2)2-κ2P,P] (22), with the ligands exhibiting bridging and chelating modes of coordination. The crystal structures of 3, 7, 8, 11, 12, 15 and 19 have been established by X-ray diffraction studies.

Graphical abstractThis paper describes the transition metal chemistry of N and O bridged large bite bisphosphines N,N-bis(diphenylphosphinobenzyl)-N-phenylamine and bis(2-diphenylphosphinobenzyl)ether.Figure optionsDownload full-size imageDownload as PowerPoint slide