ADDITION OF PHENYLACETYLENE TO THE MIXED-CHALCOGENIDE COMPOUNDS (CO)(6)FE-2(MU-SETE), (CO)(6)FE-2(MU-SSE), AND (CO)(6)FE-2(MU-STE) - STRUCTURAL CHARACTERIZATION OF (CO)(6)FE-2(MU-SEC(H)=C(PH)TE)

From the room-temperature reaction of the mixed-chalcogenide compound Fe-2(CO)(6)(mu-SeTe) with phenylacetylene two isomeric products were i solated, Fe-2(CO)(6){mu SeC(H)=C-(Ph)Te} (1) and Fe-2(CO)6{mu-SeC(Ph)= C(H)Te} (2). Fe-2(CO)(6)(mu-SSe) reacted with phenylacetylene to form Fe-2(CO)(6){mu-SC(Ph)=C(H)Se} (3). The room-temperature reaction of Fe -2(CO)(6)(mu-STe) with phenylacetylene also yielded two isomeric produ cts, Fe-2(CO)(6)(mu-SC-(H)=C(Ph)Te) (4) and Fe-2(CO)(6)(mu-SC(Ph)=C(H) Te) (5). In ah of these reactions, the homochalcogenide compounds Fe-2 (CO)(6)(mu-EC(H)=C(Ph)E) (E = Se, Te, E = S, Se, and E = S, Te, respec tively) were also formed in trace amounts. The new compounds 1-5 were characterized by IR and H-1, C-13, Se-77, and Te-125 NMR spectroscopy. Compound 1 was structurally characterized by single-crystal X-ray dif fraction methods. It crystallized in the triclinic space group P $($) over bar$$ 1 with a = 7.773(9) Angstrom, b = 10.635(9) Angstrom, c = 1 2.010(10) Angstrom, a = 104.99(10)degrees, beta = 102.86(11)degrees, g amma = 106.38(9)degrees, V = 872.1(8) Angstrom(3), Z = 2, and D(calc) = 2.241 g cm(-3).Full-matrix least-squares refinement of 1 converged t o R = 0.077 and R(w) = 0.086.