Synthesis and Reactivity of Triruthenium Carbonyl Cluster Complexes Containing a Bridging 1-Azavinylidene Ligand Derived from Benzophenone Imine

Abstract

The reaction of [Ru3(CO)12] with the lithium salt of benzophenone imine (LiNCPh2) followed by protonation with trifluoroacetic acid leads to the η1-1-azavinylidene cluster complex [Ru3(μ-H)(μ-NCPh2)(CO)10] (1). Compound 1 cannot be prepared by direct reaction of [Ru3(CO)12] with benzophenone imine under thermal conditions. Carbonyl substitution and thermolysis reactions on compound 1 and on some of its derivatives are described. Complex 1 reacts with 1 and 2 equiv of bis(diphenylphosphino)methane (dppm) at room temperature to give the substituted derivatives [Ru3(μ-H)(μ-NCPh2)(μ-dppm)(CO)8] (2) and [Ru3(μ-H)(μ-NCPh2)(μ-dppm)(dppm)(CO)7] (3), respectively. In both complexes the three bridging ligands span the same Ru−Ru edge; in addition, complex 3 contains an η1-dppm ligand occupying an equatorial site on the unique Ru atom. An X-ray structure analysis of 3·0.5CH2Cl2 is reported. Thermolysis of complex 2 in THF at reflux temperature leads to [Ru3(μ-H)(μ3-NCPh2)(μ-dppm)(CO)7] (4), a compound which contains a bridging η2-1-azavinylidene ligand interacting with the three Ru atoms. Complex 4 reacts with CO (1 atm, 18 °C) reverting to complex 2. The reaction of compound 1 with PPh3 at room temperature gives the monosubstituted derivative [Ru3(μ-H)(μ-NCPh2)(PPh3)(CO)9] (5), in which the P-donor ligand is attached to one of the two bridged Ru atoms. Thermolysis of 5 in THF at reflux temperature leads to [Ru3(μ-H)(μ3-NCPh2)(PPh3)(CO)8] (6), which, as complex 4, contains a face-bridging η2-1-azavinylidene ligand. The reaction of complex 5 with PPh3 occurs only at higher temperatures (40−70 °C) to give the asymmetrically disubstituted derivative [Ru3(μ-H)(μ-NCPh2)(PPh3)2(CO)8] (7), which has the additional PPh3 ligand attached to the unbridged Ru atom. Compound 7 is thermally unstable, undergoing an easy (40−70 °C) orthometalation reaction of a phenyl ring of the azavinylidene ligand to give the derivative [Ru3(μ-H)2(μ-NCPhC6H4)(PPh3)2(CO)7] (8). This compound reacts with CO (1 atm, 18 °C) to regenerate complex 7.

Reactivity of Triosmium and Triruthenium Carbonyls with 2,2‘-Diamino-1,1‘-binaphthalene. Synthesis of C-and N-Metalated Derivatives

“…may result in the formation of anionic derivatives [Ru 3 (µ-X)(CO) 10 ] -, which can be subsequently protonated to give [Ru 3 (µ-H)(µ-X)(CO) 10 ]. 25 We have previously reported that the compounds [Ru 3 -(µ-H)(µ-η 1 -NdCPh 2 -N)(CO) 10 ] 23 …”

Reaction of BH4−with {Mo2Cp2(μ-SMe)n} species to give tetrahydroborato, hydrido or dimetallaborane compounds: control of product by ancillary ligands

“…The azavinylidene N1-C2 bond distance [1.234( 7) Å] accords with a bond order of two. 31 The closest structural comparison to 10 is provided by the quadruply-bridged Mo(III)-Mo(III) compound [Mo 2 Cp 2 (-SMe) 3 (-NC(H)Me)] (14), 7 which differs from 10 by having a -thiolato instead of a -phosphido ligand trans to the azavinylidene group. The mean Mo-N distances in 14 and 10 [2.078(8) and 2.116(3) Å] demonstrate yet again that phosphide exerts a high trans-influence (see sections 2.1.1 and 2.1.3 above).…”

“…4 : 1 H NMR /ppm (CDCl 3 ; 298 K) : 7.3-7.0 (m,10H,Ph), 5.47 (s,10H,C 5 H 5 ), 1.57 (s,3H,SMe), 1.49 (s,3H,SMe), 0.82 (s,3H,SMe). 31 P{ 1 H} NMR /ppm (CDCl 3 ; 298 K) : 88.7 (s, -PPh 2 ). 7 : 1 H NMR /ppm (CDCl 3 ; 298 K) : 8.23 (AB,2H,Ph), 7.3-7.0 (m,8H,Ph), 5.57 (s,5H,C 5 H 5 ), 5.42 (s,5H,C 5 H 5 ), 2.82 (s,3H,SMe).…”

Syntheses, structures, and anticancer activity of novel organometallic ruthenium–maltol complexes

“…In 2, the equatorial Ru(2)eCO bond length is 1.886(4) while the two axial Ru(2)eCO bond lengths average 1.924 (4); this difference in bond distances is due to the substitution of an equatorial carbonyl ligand by a triphenylphosphine at Ru (2). The RueP bond distance of 2.376(10) is comparable to other structurally characterized triruthenium clusters containing phosphines [11,33]. The greatest structural difference between 1 and 2 is in the angle between the best planes of the two coordinated C 6 H 5 O 3 À1 ligands.…”