(2-Pyridyloxy)arsines as ligands in transition metal chemistry: a stepwise As(iii) -> As(ii) -> As(i) reduction

摘要

Neutral inherently tri- and tetradentate ligands of the type Ph3-xAs(PyO)(x)(x= 2 (1), 3 (2)) have been synthesized and characterized. Reaction of1with [RuCl2(PPh3)(3)] affords complex [PhAs(mu-PyO)(2)RuCl2(PPh3)] (3), whereas2and [RuCl2(PPh3)(3)] react with formation of [As(mu-PyO)(2)RuCl(PPh3)(2)] (5) and [Ph3P(PyO)]Cl (6). Treatment of complex5with [AuCl(tht)] (tht = tetrahydrothiophene) results in liberation of tht and formation of [AuCl(As(PyO)(2))RuCl(PPh3)(2)] (7), featuring an (Au-As-Ru) core. For compounds3,5, and7the As-Ru and As-Au bond situation has been investigated using NBO, AIM and ELF analysis, allowing the assignment of pronounced canonical forms of sigma-(As-III -> Ru-II) to3, sigma-(As-II-Ru-I) to5and sigma-(Au-I <- As-I -> Ru-II) to7.