Insertion reactions of CS2, COS, and PhNCS at thiolate-bridged diiron centers.

Treatment of [Cp*Fe(mu(2)-SR)(3)FeCp*] (1a, R = Et; 1b, R = Me) with CS(2) obtains the insertion products [Cp*Fe(mu(2)-SR)(2)(mu-eta(2)-S(2)CSR)FeCp*] (2a, R = Et; 2b, R = Me) with the retained Fe(2)S(2) subunit in excellent yield. 2a and 2b represent the first examples for the CS(2) activation and incorporation at the diiron-SR bond. [Cp*Fe(mu(2)-SEt)(2)(mu-eta(2)-S(2))FeCp*] (3) is prepared from COS and 1a through the decarbonylation and sulfur coupling reaction of COS resulting in the formation of S(2)(2-) ligand. Addition of PhNCS into 1a affords a mononuclear complex [Cp*Fe(SEt)(eta(2)-SC(SEt)NPh)] (4). 1a is found to be unreactive towards CO(2). The spectral characterization, X-ray diffraction analysis, and electrochemistry of the insertion products have also been described.