C-N coupling between µ-aminocarbyne and nitrile ligands promoted by tolylacetylide addition to [Fe2CN(Me)(Xyl)}(CO)(CO)(NCCMe3)(Cp)2][SO3CF3]: formation of a novel bridging allene-diaminocarbene ligand

The reaction of the mu-aminocarbyne complex [Fe-2{mu-CN(Me)(Xyl)}(mu-CO)(CO)(NCCMe3)(CP)(2)][SO3CF3] (2) (Xyl = 2,6-Me2C6H3) with tolylacetylide, followed by treatment with HSO3CF3 affords the complex [Fe-2{mu-eta(1):eta(3)C(Tol)double bondCdouble bondC(CMe3)N(H)CN(Me)(Xyl)}(mu-CO)(CO)(Cp-2)][SO3CF3] (3) (Tol = 4-MeC6H4). The X-ray molecular structure of 3 reveals the peculiar character of the bridging ligand, which exhibits both eta(1):eta(2) allene and aminocarbene nature. The formation of 3 proceeds through several intermediate species, which have been detected by IR spectroscopy. Addition of HSO3CF3 at an early stage of the reaction between 2 and LiCdropCTol leads to the formation of the imine complex [Fe-2{mu-CN(Me)Xyl}(mu-CO)(CO){NHC(CdropCTol)CMe3}(Cp)(2)][SO3CF3] (6) indicating that the first step of the reaction consists in the acetylide addition at the coordinated NCCMe3. The molecular structure of 6 has been elucidated by an X-ray diffraction study

Acetonitrile activation in diiron µ-carbyne complexes: synthesis and structure of the cyanomethyl complex [Fe2(MU-CNMe2)(CH2CN)(MU-CO)(CO)(Cp)2]

Reactions of [Fe2{μ-CN(Me)R}(μ-CO)(CO)(NCMe)(Cp)2]SO3CF3 (R=Me, 2a; CH2Ph, 2b; 2,6-Me2C6H32c) with LiBun afford the corresponding cyanomethyl complexes [Fe2{μ-CN(Me)R}(μ-CO)(CO)(CH2CN)(Cp)2] (3a–c), presumably via deprotonation and rearrangement of the coordinated acetonitrile. Likewise, the benzylnitrile complex [Fe2{μ-CN(Me)(2,6-Me2C6H3)}(μ-CO)(CO)(NCCH2Ph)(Cp)2]SO3CF3 yields [Fe2{μ-CN(Me)(2,6-Me2C6H3)}(μ-CO)(CO)(CH(CN)Ph)(Cp)2] (3d). The X-ray molecular structure of 3a has shown the expected stereogeometry and significant asymmetry of the bridging ligands. Deprotonation and rearrangement of the coordinated MeCN are not observed in the thiocarbyne complex [Fe2(μ-CSMe)(μ-CO)(CO)(NCMe)(Cp)2]SO3CF3 (5) in spite of the similarities with 2a–c. However, compound 5 readily reacts with Li2Cu(CN)R2 (R=Me, Ph) to form the thiocarbene complexes [FeSme}(μ-CO)(CO)(Cp)2] (6a–b), with displacement of the acetonitrile ligand

One-Pot Synthesis of the New Dianionic Ligand [Na]2[C5H4CO2(CH2)2NTs]; Preparation and Structures of Two Rhodium Derivatives

The new dianionic ligand [Na]2[C5H4CO2(CH2)2NTs] (1) having an alkoxycarbonyl and an amide group in the same side chain has been prepared by a single step, high yield procedure. The synthesis of the related rhodium complexes [Rh{5-C5H4CO2(CH2)2N(H)Ts}(NBD)] (3) and [Rh{5-C5H4CO2(CH2)2N(Me)Ts}(NBD)] (4) is reported as well as their X-ray molecular structures

Synthesis and characterization of new diiron and diruthenium MU-aminocarbyne complexes containing S, P and C-ligands

The diiron aminocarbyne complexes [Fe2{µ-CN(Me)(R)}(µ-CO)(CO)(NCMe)(Cp)2][SO3CF3] (R = Xyl, 1a; R = Me, 1b; R =CH2Ph, 1c; Xyl = 2,6-Me2C6H3) undergo replacement of the coordinated nitrile by halides, diethyldithiocarbamate, and dicyanomethanide to give [Fe2{µ-CN(Me)(R)}(µ-CO)(CO)(X)(Cp)2] complexes (R = Me, X = Br, 4a; R = Me, X = I, 4b; R =CH2Ph, X =Cl, 4c; R =CH2Ph, X = Br, 4d; R =CH2Ph, X = I, 4e; R = Xyl, X = SC(S)NEt2, 5a; R = Me, X = SC(S)NEt2, 5b; R = Xyl, X = CH(CN)2, 7), in good yields. The molecular structure of 5a shows an unusual η1 coordination mode of the dithiocarbamate ligand. Similarly, treatment of [M2{µ-CN(Me) (R)}(µ-CO)(CO)(NCMe)(Cp)2][SO3CF3] (M = Fe, R = Xyl, 1a; M = Fe, R = Me, 1b; M = Ru, R = Xyl, 2a; M = Ru, R = Me, 2b) with a series of phosphanes generates the cationic complexes [M2{µ-CN(Me)(R)}(µ-CO)(CO)(P)(Cp)2][SO3CF3] (M = Fe, R = Xyl, P = PPh2H, 6a; M = Fe, R = Xyl, P = PPh3, 6b; M = Fe, R = Xyl, P = PMe3, 6c; M = Fe, R = Me, P = PMe2Ph, 6d; M = Fe, R = Me, P = PPh3, 6e; M = Fe, R = Me, P = PMePh2, 6f; M = Ru, R = Xyl, P = PPh2H, 6g; M = Ru, R = Me, P = PPh2H, 6h), in high yields. The molecular structure of 6a has been elucidated by an X-ray diffraction study. The reactions of [Fe2{µ-CN(Me)(Xyl)}(µ-CO)(CO)(NCR )(Cp)2][SO3CF3] [R =Me, 1a; R = tBu, 3] with PhLi and PPh2Li yield [Fe2{µ-CN(Me)(Xyl)}(µ-CO)(CO)(Ph)(Cp)2] (8) and [Fe2{µ-CN(Me)(Xyl)}(µ-CO)(CO)(PPh2)(Cp)2] (9), respectively. The molecular structure of 8 has been ascertained by X-ray diffraction. Conversely, the reaction of 1a with MeLi generates the aminoalkylidene compound [Fe2{C(Me)N(Me)(Xyl)}(µ-CO)2(CO)(Cp)2] (10). Finally, the acetone complex [Fe2{µ-CN(Me)(Xyl)}(µ-CO)(CO)(OCMe2)(Cp)2][SO3CF3] (12) reacts with lithium acetylides to give complexes [Fe2{µ-CN(Me)(Xyl)}(µ-CO)(CO)(C≡CR)(Cp)2] (R = p-C6H4Me, 11a; R = Ph, 11b; R = SiMe3, 11c), in high yields. Filtration through alumina of a solution of 11a in CH2Cl2 results in hydration of the acetylide group and C–Si bond cleavage, affording [Fe2{µ-CN(Me)(Xyl)}(µ-CO)(CO){C(O)Me}(Cp)2] (12)

Crystal structure of tri-\uf06d-carbonyl-octacarbonyl-iodo-tetrahedro-tetracobaltate(1-) as its tetraethylammonium salt

The complex [NEt4][Co4(CO)11I] crystallizes in the orthorhombic space group Cmca with unit-cell dimensions a= 16.97(1), b= 26.72(1), c= 12.10(1)\uc5, and Z= 8. The structure has been solved from X-ray single-crystal counter data and refined by least-squares calculations to R= 0.063 for 1 874 significant diffraction intensities. The structure of the anion is derived from that of the parent [Co4(CO)12]. Three of the carbonyl groups are edge bridging, defining a basal triangle, and eight are terminal, two per metal atom. The iodine atom, contrary to expectation, is terminally bonded to the apical cobalt atom. The molecular symmetry is Cs-m. The Co\u2013I distance is 2.642(2)\uc5, and the Co\u2013Co interactions have mean values 2.47 and 2.52 \uc5 for the bridged and unbridged edges, respectively. A slight disorder, caused by the presence of 2% of an isomer with the iodine in a basal position, is present

Reactivity of [Co4(CO)12].Synthesis and characterization of tetracobalt carbonyl anions of general formula [Co4(CO)11X]

Salts of the green-brown anions [Co4(CO)11X]- (X = Br, I, or SCN) have been obtained at -70 \ub0C starting from [Co4(CO)12] and tetrasubstituted ammonium ([NEt4] Br or [NEt4]I) or phosphonium {[PMePh3]Br, [N(PPh3)2]I, or [N(PPh3)2][SCN]} salts. Using sodium alkoxides or propylamine, formation of purple-red solutions containing, on the basis of the i.r. spectra, similar monosubstituted anions (X = COOMe, COOPri, or CONHPrn) has been observed. The transformation of [Co4(CO)12] into [Co2(CO)8] has been studied in PriOH at room temperature under cabron monoxide. The considerable acceleration of the rate of this reaction by halide ions is in agreement with the ready decomposition observed for all the [Co4(CO)11X]- anions in Lewis-base solvents