PHOTOCHEMICAL-REACTIONS OF ALKYNYL IRON (LI) COMPLEXES WITH CARBON-DISULFIDE - INSERTION OF CS2 INTO AN IRON-C(SP) BOND

The novel alkynyldithiocarboxylate complexes [Fe(eta(5)-C5H5) (S2CC eq uivalent to CR) (dppm-P)] (3a,b) and [Fe(eta(-)C(5)H(5))(S2CC equivale nt to CR)(PPh(3))] (4a,b) were obtained through the insertion of CS2 i nto the iron-alkynyl bond in the complexes [Fe(eta(5)-C5H5)(C equivale nt to CR)(L)(L'] L, L' = dppm R = Ph (1a),(t)Bu (1b); L = (CO), L' = ( PPh(3)) R = Ph (2a), (t)Bu (2b). variable-temperature P-31{H-1} NMR st udies indicate the presence of two different isomers, [Fe(eta(5)-C5H5) (eta(3)-S,C,S'-S2CC equivalent to CR)(L)(L')] and [Fe(eta(5)-C5H5)(et a(2)-S,S'-S2CC equivalent to CR)(L)(L')], which rapidly interconvert a t room temperature. The synthesis of the precursor complex [Fe(eta(5)- C5H5)(C equivalent to C(t)Bu)(CO)(PPh(3))] is also described.