An Organometallic Radical Route to Bis(phosphido)- and Hydrido−Phosphido-Bridged Metal−Metal-Bonded Complexes of Cyclopentadienylchromium via Desulfurization of Thiophosphinito Ligands

Abstract

The reaction of [CpCr(CO)3]2 (1, Cp = η5-C5H5) with 1 mol equiv of the tetraalkyldiphosphine disulfide R2P(S)P(S)R2 (R = Me, Et) at 60 °C for 24 h led to the isolation of the thiophosphinito complexes CpCr(CO)2(SPR2) (2a, R = Me; 2b, R = Et) as dark red solids in ca. 24% yield. Desulfurization of 2a by the organometallic radical CpCr(CO)3 • (1A) gave the hydrido−phosphido-bridged complex Cp2Cr2(CO)4(μ-H)(μ-PMe2) (3a), the bis(μ-phosphido) metal−metal doubly bonded complex Cp2Cr2(CO)2(μ-PMe2)2 (4a), and the triangulo trinuclear complex Cp3Cr3(CO)3(S)(PMe2) (5a). The solid-state structures of all of the complexes have been determined by single-crystal X-ray diffraction analysis.

Homolytic Cleavage and Aggregation Processes in Cyclopentadienylchromium Chemistry

“…The further reaction of the η 2 -arylthioxophosphane product CpCr(CO) 2 (SP(H)Ar) (17) with 1 under thermolytic conditions led to the isolation of the hydrido-phosphidobridged complex Cp 2 Cr 2 (CO) 4 (H)(P(H)Ar) (20), Cp 2 Cr 2 -(CO) 2 (P(H)Ar) 2 (21), the phosphinidene cuboidal complexes Cp 4 Cr 4 S 3 (PAr) (22) and Cp 4 Cr 4 S 2 (PAr) 2 (23), CpCr-(CO) 3 H (13), and Cp 4 Cr 4 S 4 (7) (Scheme 10). 23b The formation of the products can again be rationalized by pathways arising from the thiophilicity and homolytic bond cleavage ability of 1A (Scheme 11).…”

A tert-butyl/cyano substituted (1,2,3,5-dithiadiazolyl)benzene and η2 π complexes with CpCr(CO)2

“…Thus, the resulting primary products, A, from dibenzothiazolyl disulfide [(C 6 H 4 )-NSCS] 2 [8], B, tetraalkylthiuram disulfanes (R 2 NC(S)S) 2 [9], C, tetraalkyldiphosphine disulfide [10], D and E, diphenyl dichalcogenide Ph 2 E 2 (X = S, Se, Te) [11], F, thiophosphorus compounds bis(diphenylthiophosphinyl)disulfane (Ph 2 P(S)S) 2 [12], or the analogous bis(thiophosphoryl)-disulfane [(RO) 2 P(S)S] 2 (R = i Pr) [13], are the inevitable consequence of the coupling of 2 and organic sulfur-or phosphorus-centered radicals, under conditions where thermally induced radical cleavage of E-E bonds occurs.…”

Gold(III) Phenylphosphides and -phosphodiides

“…During the past few years, various research groups have contributed to the development of the chemistry of phosphido complexes of main group − or transition − metals, with phosphido ligands that bridge metal centers. There is a great number of compounds of this type containing metals mainly of groups 6 − or 10, − whereas the number of gold phosphides is much lower, despite the great attention that the synthesis of di- and polynuclear phosphido-bridged complexes attracts because of their possible catalytic behavior …”