Mixed-Metal Cluster Chemistry. 28. Core Enlargement of Tungsten−Iridium Clusters with Alkynyl, Ethyndiyl, and Butadiyndiyl Reagents

Abstract

Reaction of [WIr3(mu-CO)3(CO)8(eta-C5Me5)] (1c) with [W(C[triple bond]CPh)(CO)3(eta-C5H5)] afforded the edge-bridged tetrahedral cluster [W2Ir3(mu4-eta2-C2Ph)(mu-CO)(CO)9(eta-C5H5)(eta-C5Me5)] (3) and the edge-bridged trigonal-bipyramidal cluster [W3Ir3(mu4-eta2-C2Ph)(mu-eta2-C=CHPh)(Cl)(CO)8(eta-C5Me5)(eta-C5H5)2] (4) in poor to fair yield. Cluster 3 forms by insertion of [W(C[triple bond]CPh)(CO)3(eta-C5H5)] into Ir-Ir and W-Ir bonds, accompanied by a change in coordination mode from a terminally bonded alkynyl to a mu4-eta2 alkynyl ligand. Cluster 4 contains an alkynyl ligand interacting with two iridium atoms and two tungsten atoms in a mu4-eta2 fashion, as well as a vinylidene ligand bridging a W-W bond. Reaction of [WIr3(CO)11(eta-C5H5)] (1a) or 1c with [(eta-C5H5)(CO)2 Ru(C[triple bond]C)Ru(CO)2(eta-C5H5)] afforded [Ru2WIr3(mu5-eta2-C2)(mu-CO)3(CO)7(eta-C5H5)2(eta-C5R5)] [R = H (5a), Me (5c)] in low yield, a structural study of 5a revealing a WIr3 butterfly core capped and spiked by Ru atoms; the diruthenium ethyndiyl precursor has undergone Ru-C scission, with insertion of the C2 unit into a W-Ir bond of the cluster precursor. Reaction of [W2Ir2(CO)10(eta-C5H5)2] with the diruthenium ethyndiyl reagent gave [RuW2Ir2{mu4-eta2-(C2C[triple bond]C)Ru(CO)2(eta-C5H5)}(mu-CO)2(CO)6(eta-C5H5)3] (6) in low yield, a structural study of 6 revealing a butterfly W2Ir2 unit capped by a Ru(eta-C5H5) group resulting from Ru-C scission; the terminal C2 of a new ruthenium-bound butadiyndiyl ligand has been inserted into the W-Ir bond. Reaction between 1a, [WIr3(CO)11(eta-C5H4Me)] (1b), or 1c and [(eta-C5H5)(CO)3W(C[triple bond]CC[triple bond]C)W(CO)3(eta-C5H5)] afforded [W2Ir3{mu4-eta2-(C2C[triple bond]C)W(CO)3(eta-C5H5)}(mu-CO)2(CO)2(eta-C5H5)(eta-C5R5)] [R = H (7a), Me (7c); R5 = H4Me (7b)] in good yield, a structural study of 7c revealing it to be a metallaethynyl analogue of 3.

Cyclopentadienyl chromium and tungsten complexes with halide, methyl and σ-phenylethynyl ligands: Structures of (η5-C5H5)Cr(NO)2(–CC–C6H5), (η5-C5H5)Cr(NO)2I and [(η5-C5H4)-COOCH3]W(CO)3Cl

“…Preparation of (g 5 -cyclopentadienyl)dinitrosyl(phenylethynyl) chromium (5) As this product is light sensitive, all operations were carried out with the exclusion of light. (g 5 -cyclopentadienyl)dinitrosylchlorochromium (1) (0.17 g, 0.81 mmol) was dissolved in 25 ml of diethylamine and phenylacetylene (0.11 ml, 0.98 mmol) was added while stirring.…”

“…Herein, we report thorough spectral studies on 1-13, and the crystal structures of (g 5 -C 5 H 5 )Cr(NO) 2 I (3), (g 5 -C 5 …”

“…For the analogue of CpCr(NO) 2 CH 3 (4) there is only one, (C 5 H 4 COOCH 3 )Cr(NO) 2 CH 3 [1], and for complex CpW(CO) 3 CH 3 there are 18 [4]. For Cp derivatives of compound CpCr(NO) 2 -(C"C-C 6 H 5 ) (5) and CpW(CO) 3 (C"C-C 6 H 5 ) [5], there are none.…”

Mixed-metal cluster chemistry. 35. Syntheses and structural studies of Mo 3 Ir 3 (μ 3 -O)(μ-CO) 3 (CO) 8 ( η 5 -C 5 H 5 ) 3 , Mo 4 Ir 4 (μ-CO) 4 (CO) 9 ( η 5 -C 5 H 5 ) 4 and Mo 3 Ir 5 (μ-CO) 3 (Cl)(CO) 6 ( η 5 -C 5 H 5 ) 3 ( η 5 -C 5 HMe 4 )

“…The IreIr [2.7410(9)e2.7546 (8) 12 (h 5 -C 5 Me 5 ) sits in a butterfly cleft formed by the edge-bridging Ru and a WRu 2 face of the WRu 4 trigonal bipyramid and, while this cluster is the closest structural analogue to 1, the m 4 -coordination of its carbido ligand in the analogous environment to the m 3 -atom in 1 lends further support to assignment of the latter as an oxo ligand. The core atom disposition in 1 is analogous to those in W 3 Ir 3 (m 4 -h 2 -CO)(m-CO)(CO) 10 (h 5 -C 5 H 4 Me) 3 [19] and W 3 Ir 3 (m 4 -h 2 -C 2 Ph)(m-h 2 -C]CHPh)(Cl)(CO) 8 (h 5 -C 5 Me 5 )(h 5 -C 5 H 5 ) 2 [20], in both of which a group 6 metal atom M bridges an IreIr bond and the multiply-bridging ligand sits in the resultant M 2 Ir 2 butterfly cleft.…”

“…The coordination geometry is completed by a terminal chloro ligand. The source of the chlorine is as yet unclear: a similar terminal chloro ligand was identified in W 3 Ir 3 (m 4 -h 2 -C 2 Ph)(m-h 2 -C]CHPh)(Cl)(CO) 8 (h 5 -C 5 Me 5 )(h 5 -C 5 H 5 ) 2 [20] and assumed to derive from trace amounts of HCl in the CH 2 Cl 2 solvent. In contrast to the present study, the chloro ligand in W 3 Ir 3 (m 4 -h 2 -C 2 Ph)(m-h 2 -C]CHPh)(Cl)(CO) 8 C 5 HMe 4 )} ¼ 102 CVE, which is six less than the PSEPT-predicted electron count [2,29].…”