Synthesis and X-ray Crystallographic Structural Determination of the Acetylene Complex (ETA5-C5H5)2W2(CO)4(C2H2).

Reaction of photogenerated (ETA5-C5H5)2W2(CO)4 with acetylene at 25 yields a complex of the formula (ETA5-C5H5)2W2(CO)4(C2H2). The crystal structure of the complex shows it to have a tetrahedrane-like W2C2 core. The C-C bond distance of the C2H2 unit is 1.35 Angstrom which is close to that of ethylene, considerably longer than the 1.20 Angstrom for acetylenes. The W-W distance is 2.973 Angstrom which is approx. 0.25 Angstrom shorter than the W-W distance in (ETA5-C5H5)2W2(CO)6 but longer than that expected for (ETA5-C5H5)2W2(CO)4. (Author)
Prepared in cooperation with University of Southern California, Los Angeles. Dept. of Chemistry.