Mixed-metal cluster chemistry. Part 18. Synthesis and crystal structure ofW3Ir3(mu(4)-eta(2)-CO)(mu-CO)(CO)(10)(eta-C5H4Me)(3)

Heating a mixture of W2Ir2(CO)(10)(eta -C5H4Me)(2) and 1,2-(E)-bis{4'-(oct- 1"-ynyl)phenyl}ethene in refluxing CH2Cl2 affords a complex mixture from wh ich W3Ir3(mu (4)-eta (2)-CO)(mu -CO)(CO)(10)(eta -C5H4Me)(3) can be separat ed in low yield. The crystallographically characterized title cluster is th e first hexametallic Group 6-Group 9 mixed-metal cluster, possesses an unus ual edge-bridged trigonal bipyramidal core geometry, and has a mu (4)-eta ( 2)-CO ligand which has the longest carbonyl CO bond thus far. (C) 2001 Else vier Science B.V. All rights reserved.