Reactivity of [Fe2(CO)6(μ-CO)(μ-dppm)] towards unsaturated sulfur-containing compounds, SO2, CS2 and ArNCS: facile carbon–sulfur bond cleavage at the diiron centre
摘要:
Photolysis of [Fe(2)(CO)(6)(mu-CO)(mu-dppm)] (1) with SO(2), CS(2) and ArNCS leads to the formation of [Fe(2)(CO)(6)(mu-SO(2))(mu-dppm)] (2), [Fe(4)(CO)(10)(mu(3)-S)(mu-CS)(mu-dppm)(2)] (3), [Fe(2)(CO)(3)(CNAr){mu-SC(NAr)C(O)S}(mu-dppm)] (4-5) and [Fe(2)(CO)(4){mu-SC(N-p-tolyl)C(O)S}(mu-dppm)] (6), respectively. Complex 2 is a simple CO substitution product, white in 3 carbon-sulfur cleavage and coupling of diiron units has occurred. Dithiolate-bridged 4-6 also result from carbon-sulfur bond cleavage of one isothiocyanate and coupling of the sulfur with CO and a second isothiocyanate. Two isomers of complexes 3-6 are found and in thiolate-bridged 4-6 these interconvert as a result of inversion at the imine nitrogen, which has been monitored by VT NMR. (C) 2000 Elsevier Science S.A. All rights reserved.