Iron carbonyls with bulky thiolate ligands: crystal structures of [Fe-2(CO)(6)(mu-(SC6H2Pr3)-Pr-i-2,4,6)(2)] and ((C6H2Pr3)-Pr-i-2,4,6)(2)S-2

The reaction of Fe-3(CO)(12) and bulky thiols HSR (R = (C6H2Pr3)-Pr-i-2,4,6 ; C6H2Me3-2,4,6) in toruene yielded compounds [Fe-2(CO)(6)(mu-SR)(2)] (R = (C6K2Pr3)-Pr-i-2,4,6 (1), C6H2Me3-2,4,6 (2)). The substitution of one carbo nyl by the phosphine Ph2P(CH2)(2)Si(OEt)(3) in complex 1 afforded {Fe-2(Co) (5)[Ph2P(CH2)(2)Si(OEt)(3)](mu-(SC6H2Pr3)-Pr-i-2,4,6)(2)} (3). Mononuclear compounds [(eta(5)-C5H5)Fe(Co)(2)((SC6H2Pr3)-Pr-i-2,4,6)] (4) and {(eta(5)- C5H5)Fe(Co)[Ph2P(CH2)(2)Si(OEt)(3)]((SC6H2Pr3)-Pr-i-2,4,6)} (5) have also b een obtained. Compound 1 has been studied by X-ray diffraction and the stru cture determined reveals a distorted octahedron geometry around each iron a tom and confirms the anti arrangement of R substituents, R = (C6H2Pr3)-Pr-i -2,4,6, in the molecule. The preparation of thiol (HSC6H2Pr3)-Pr-i-2,4,6 yi elded the disulfide ((C6H2Pr3)-Pr-i-2,4,6)(2)S-2 as a by-product, whose str ucture has been solved by X-ray diffraction. (C) 1999 Elsevier Science S.A. All rights reserved.