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The ruthenium-triphos and diphosphine-catalysed amination of alcohols with ammonia is reported. Various types of triphos derivatives with electron-donating functional group were synthesized and used as ligands in the Ru-catalysed alcohol amination with NH3. The triphos derivatives are effective for the formation of primary amines. On the other hand, if hemilabile diphosphines as tridentate ligands are used, mixtures of secondary-along with primary amines are obtained. It was found that even simple diphosphines can be used as ligands for the selective formation of the secondary amines. The diphosphine system allows a new entry to the Ru-catalysed formation of secondary amines.

Reaction of [PdClMe(P^N)2] with SnCl2 followed by Cl-abstraction leads to apparent Pd-C bond activation, resulting in methylstannylene species trans-[PdCl{(P^N)2SnClMe}][BF4] (P^N = diaryl phosphino-N-heterocycle). In contrast, reaction of Pt analogues with SnCl2 leads to Pt-Cl bond activation, resulting in methylplatinum species trans-[PtMe{(P^N)2SnCl2}][BF4]. Over time, they isomerise to methylstannylene species, indicating that both kinetic and thermodynamic products can be isolated for Pt, whereas for Pd only methylstannylene complexes are isolated. Oxidative addition of RSnCl3 (R = Me, Bu, Ph) to M(0) precursors (M = Pd or Pt) in the presence of P^N ligands results in diphosphinostannylene pincer complexes trans-[MCl{(P^N)2SnCl(R)}][SnCl4R], which are structurally similar to the products from SnCl2 insertion. This showed that addition of RSnCl3 to M(0) results in formal Sn-Cl bond oxidative addition. A probable pathway of activation of the tin reagents and formation of different products is proposed and the relevancy of the findings for Pd and Pt catalysed processes that use SnCl2 as a co-catalyst is discussed., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Gold, silver and rhodium complexes of the diphosphine-phosphine oxide DPPO = {[o-iPr(2)P-(C(6)H(4))](2)P(O)Ph} have been prepared and characterized. Thanks to its polyfunctional character, DPPO features versatile coordination properties. According to crystallographic data, only one phosphine moiety is engaged in coordination towards (AuCl) and [RhCl(nbd)]. However, NMR data indicate fluxional behavior in solution, as the result of the exchange between the free and coordinated phosphines around the metal. Chelating coordination via the two phosphine sites is observed towards (Au(+)) and (AgCl) with PMP bite angles varying from 122° to 159°. According to X-ray and theoretical analyses, the oxygen atom of the central phosphine oxide moiety points towards the metal but does not interact significantly with it. Tridentate coordination via the two phosphines as well as the oxygen atom of DPPO occurs with [Rh(CO)(+)], leading to an original PO(P)P pincer structure.

The reaction of the diphosphine-phosphine oxide ligand {[o-iPr(2)P-(C(6)H(4))](2)P(O)Ph} with Pd(PtBu(3))(2) proceeds with cleavage of the Ph-P(O) bond to give an original κ(P,P(O),P)-pincer complex. According to DFT calculations, this oxidative addition occurs via a three-center P,C(ipso),Pd transition state., (This journal is © The Royal Society of Chemistry 2011)

The Ru[double bond, length as m-dash]P double bond in the 5-coordinate terminal phosphido complex [Ru(eta(5)-indenyl)(PR(2))(PPh(3))] undergoes regioselective [2+2] cycloaddition with simple and activated alkynes to give metallaphosphacyclobutene complexes. These unusual examples of alkyne insertion into a metal-heteroatom bond represent potentially important intermediates in stereoselective routes to new phosphine reagents and ligands.