FORMATION OF (MU-RE)(MU-S-)FE-2(CO)(6) AND (MU-RE)(MU-SE-)FE-2(CO)(6)(E=S, SE) ANIONS AND A COMPARATIVE-STUDY OF THEIR REACTIONS WITH SO2CL2, CLC(O)ZC(O)CL (Z=(CH2)(2), C6H4), OR P-MEC(6)H(4)SO(2)CL - SINGLE-CRYSTAL STRUCTURES OF [(MU-ETS)FE-2(CO)(6)](2)(MU(4)-SE) AND (MU-ETS)(MU-P-MEC(6)H(4)SO(2))FE-2(CO)(6)

The C-bridged anions [(mu-RE)(mu-CO)Fe-2(CO)(6)](-) reacted with S-8 t o form the sulfur-centered anions (mu-RE)(mu-S-)Fe-2(CO)(6) (4; E = S, Se), whereas reaction of the anions with Se-8 yielded the selenium-ce ntered anions (mu-RE)(mu-Se-)Fe-2(CO)(6) (6; E = S, Se). Interestingly , reaction of 4 with SO2Cl2 afforded the S-S-bonded clusters [(mu-RE)F e-2(CO)(6)](2)(mu-S-S) (5), whereas reaction of 6 with SO2Cl2 produced the mu(4)-S clusters [(mu-RE)Fe-2(CO)(6)](2)(mu(4)-Se) (8); clusters 8 could also be produced by the action of anions 6 on succinoyl chlori de or p-phthaloyl chloride, while the mu(4)-S clusters [(mu-RE)Fe-2(CO )(6)](2)(mu(4)-S) (9) were generated by reaction of anions 4 with the above organic bis acid chlorides under similar conditions. Also, react ion of 4 (E = S) with p-MeC(6)H(4)SO(2)Cl gave the mu(4)-S clusters [( mu-RE)Fe-2(CO)(6)](2)(mu(4)-S) (9; E = S) and the expected Fe2S2 butte rfly clusters (mu-RE)(mu-p-MeC(6)H(4)SO(2)S)Fe-2(CO)(6) (10), whereas anion 6 reacted with p-MeC(6)H(4)SO(2)Cl to afford the unexpected S = O-bridged complexes (mu-RE)(mu-p-MeC(6)H(4)SO(2))Fe-2(CO)(6) (11) and mu(4)-Se dusters 8. Clusters 11 could be also prepared through direct reaction of the precursor of 6, i.e. [(mu-RE)(mu-CO)Fe-2(CO)(6)](-), w ith p-MeC(6)H(4)SO(2)Cl. For some of these reactions the mechanisms we re preliminarily proposed, The structures of 15 new cluster compounds have been characterized by C/H analysis and IR, H-1 NMR, and MS spectr oscopy; those of [(mu-EtS)Fe-2(CO)(6)](2)(mu(4)-Se) (8a) and (mu-EtS)( mu-p-MeC(6)H(4)SO(2))Fe-2(CO)(6) (11a) have been confirmed by X-ray di ffraction analyses.