Synthesis and Reactions of Terminal Osmium and Ruthenium Complexed Phosphinidenes [(η⁶‐Ar)(L)MPMes*]

Abstract

Novel, very stable ruthenium and osmium containing terminal phosphinidene complexes [(eta(6)-Ar)(L)M=Mes*] (Ar=benzene, p-cymene; L=PR(3), CO, and RNC) have been prepared by dehydrohalogenation of novel [(eta(6)-Ar)MX(2)(PH(2)Mes*)] complexes in the presence of a stabilizing ligand. Xray crystal structures are reported for [(eta(6)-C(6)H(6))(PPh(3))Rud=PMes*] (9) and [(eta(6)-pCy)(PPh(3))Os=PMes*] (4). Dehydrohalogenation in the absence of a stabilizing ligand resulted in the new P-spiroannulated Ru(2)P(2)-ring structure 16. Dehydrohalogenation in the presence of but-2-yne gave a novel phosphaallyl complex [(eta(6)-Ar)Ru(eta(3)-R(2)PC(Me)CHMe)] 26, for which an X-ray crystal structure is reported. The mechanism by which 16 and 26 are obtained is presumed to involve the intermediate formation of the 16-electron (eta(6)-benzene)Rud=PMes* phosphinidene complex.

Preparation and Structure of Mono‐ and Binuclear Half‐Sandwich Iridium, Ruthenium, and Rhodium Carbene Complexes Containing 1,2‐Dichalcogenolao 1,2‐Dicarba‐closo‐Dodecaboranes

“…Synthesis of half-sandwich mono-, dimetallic transitionmetal N-heterocyclic carbene complexes: Metal complexes with NHC ligands were typically prepared from imidazolium salts via the three common routes: the free carbene reaction, [14] the metal acetate protocol, [15] and the silver carbene transfer. [16] Following our previous procedure of related compounds, we employed the synthesis of transition-metal complexes by transmetalation from the corresponding silver carbene derivatives which are used in situ.…”

Nucleophilic Phosphinidene Complexes: Access and Applicability

“…[60] Moreover, 42 was shown to undergo cycloaddition with alkynes to give the putative [2+2]-adduct phosphametallacyclobutene 92, which rearranges to the more stable metallaphosphabicyclobutane 93 (Scheme 27 c). [61] Ruthenium phosphinidenes 51 a generated in situ also react with alkynes, as shown by Lammertsma and co-workers, [40] to give the stable phosphaallyl complexes 95 (Scheme 27 d). It was reasoned that first [2+2]-cycloadduct 94 is formed, which subsequently undergoes CÀH activation to yield the final product.…”

“…[41] The heavier osmium phosphinidene complexes [h 6 -Ar(L)Os=PÀMes*] (47 b, Ar= benzene, p-cymene; L = PPh 3 , PMe 3 , CO) were obtained equally readily from dehydrohalogenation ligation of the primary complexed phosphine [h 6 -ArOsX 2 (PH 2 Mes*)] (46 b). [40] Similar to the third-row Group 9 transition metal iridium, the CO-ligated osmium complex [h 6 -Ar(CO)Os=PÀMes*] (47 b) could also be isolated. The E isomers were shown to be favored for complexes having large PR substituents (e.g.…”

“…[40] Ruthenium phosphinidenes [h 6 -pCym(R 3 P)Ru = P-Mes*] 47 a (R = Ph, Cy) are also accessible from [h 6 -pCymRuCl 2 (PR 3 )] by reaction with DBU and PH 2 Mes*. [41] The heavier osmium phosphinidene complexes [h 6 -Ar(L)Os=PÀMes*] (47 b, Ar= benzene, p-cymene; L = PPh 3 , PMe 3 , CO) were obtained equally readily from dehydrohalogenation ligation of the primary complexed phosphine [h 6 -ArOsX 2 (PH 2 Mes*)] (46 b).…”

N‐Heterocyclic Carbene Functionalized Iridium Phosphinidene Complex [Cp*(NHC)IrPMes*]: Comparison of Phosphinidene, Imido, and Carbene Complexes

“…Recently, our group reported on stable Group 8 and 9 phosphinidene complexes of the type [(h 6 -Ar)(L)MPAr] (M Ru, Os) [8] and [(h 5 -Cp R )(L)MPAr] (M Co, Rh, Ir). [9,10] A unique aspect of these novel complexes concerns the facile variation of stabilizing ligand L. So far, established ligands such as phosphines, arsines, phosphites, isocyanides and carbon monoxide have been introduced successfully, leading to stable, isolable complexes with strong metalÀligand bonds.…”