Ruthenium mediated halogenation of white phosphorus: synthesis and reactivity of the unprecedented P4Cl2 moiety

ISSN:1477-9226ISSN:1477-923

Metal‐Assisted Opening of Intact P 4 Tetrahedra

The reactivity of ruthenium and manganese complexes bearing intact white phosphorus in the coordination sphere was investigated towards the low-valent transition-metal species [Cp ''' o] (Cp '''=eta(5)-C5H2-1,2,4-tBu(3)) and [(LM)-M-0] (L-0 = CH[CHN(2,6-Me2C6H3)] 2; M= Fe, Co). Remarkably, and irrespective of the metal species, the reaction proceeds by the selective cleavage of two P-P edges and the formation of a square-planar cyclo-P-4 ligand. The reaction products [{CpRu(PPh3)(2)}{CoCp '''}(mu,eta(1:4)-P-4)][CF3SO3] (5), [{(CpMn)-Mn-BIG(CO)(2)}(2){CoCp '''}(mu,eta(1:1:4)-P-4)] (6) and [{(CpMn)-Mn-BIG(CO)(2)}(2){ML0}(mu,eta P-1:1:4-(4))] (Cp-BIG = C-5(C(6)H(4)nBu)(5); L-0 = CH[CHN(2,6-Me2C6H3)](2); M = Fe (7a), Co (7b)), respectively, were fully characterized by single-crystal X-ray diffraction and spectroscopic methods. The electronic structure of the cyclo-P-4 ligand in the complexes 5-7 is best described as a pi-delocalized P-4(2-) system, which is further stabilized by two and three metal moieties, respectively. DFT calculations envisaged a potential intermediate in the reaction to form 5, in which a quasi-butterfly-shaped P-4 moiety bridges the two metals and behaves as an eta(3)-coordinated ligand towards the cobalt center

Ru‐P Nanoalloy from Elemental Phosphorus as P‐Source: Synthesis, Characterization and Catalytic Evaluation

International audienceBinary ruthenium-phosphorus nanoparticles (NPs) with different Ru/P ratio were prepared in mild conditions using white phosphorus (P4) as phosphorus source. Accurate study of both their morphology and structure at the atomic level by TEM and HAADF-STEM, respectively, showed that Ru2P and RuP have a narrow size distribution (ca. 3.3 nm) and are lacking an ordered ruthenium phosphide lattice. 31 P Solid State NMR highlighted the existence of three different phosphorus species consistently with the lack of a metal phosphide lattice and finally XPS revealed that the true nature of these nanoparticles can be better described as a ruthenium-phosphorus alloy. As a benchmark test, the selective hydrogenation of nitroarenes to primary aromatic amines was studied and evidenced how the P-alloying imparts a surface modification resulting in a higher catalytic activity and excellent chemoselectivity of Ru2P in comparison to Ru(0) and RuP