Niobium organometallic chemistry : IX. CS 2 complexes: synthesis, reactivity and their use as ligand; crystal structure of (n-C 4H 9)(ν 5-C 5H 5) 2Nb(μ-CS 2)W(CO) 5

Abstract

Carbon disulphide reacts with niobium complexes [Nb(η-C 5H 5) 2(Me) 2] and [Nb(η-C 5H 5) 2H (CH 2CHC 2H 5)] to produce the new η 2-CS 2 derivatives [Nb(η-C 5H 5) 2(Me)(η 2-CS 2)] ( 1) and [Nb(η-C 5H 5) 2(Bu) (η 2-CS 2)] ( 2) respectively. Treatment of 1 and 2 with methyl iodide affords the respective cationic η 2- dithioalkyl ester complexes [Nb(η-C 5H 5) 2(Me) {η 2-C(S)SMe}] I ( 3) and [Nb(η-C 5H 5) 2(Bu) {η 2-C(S)SMe}] I ( 4). Hetero-dinuclear complexes [(Bu)-(η-C 5H 5) 2Nb(η-CS 2)M(CO) n ] (M  Cr, Mo, W; n  5. M  Fe; n  4) and [(Bu)-(η-C 5H 5) 2Nb(μ-CS 2)Mn(CO) 2(η-CH 3C 5H 4)] and an homodinuclear complex [(Bu)(η-C 5H 5) 2Nb(μ-CS 2)Nb(η-C 5H 5) 2(Bu)] have been synthesized. The structure of the niobium—tungsten derivative has been determined by single-crystal X-ray diffraction. Crystal data are space group P2 1/ c, a 12.935(4), b 12.742(4), c 14.565(4) Å, β 103.27(3)°, Z  4. The Nb(μ-CS 2)W unit is planar within ±0.06 Å. The CS 2 group is η 2-bonded to niobium through a CS linkage and σ-bonded to manganese through the other sulfur atom. The 13C NMR spectra indicate that 2 has a larger σ-donor/π-acceptor ratio than CO.