In a five step synthesis cyclopentadienyl)(tetraphenylcyclobutadiene)c
obalt is produced in 19% overall yield from sodium carbomethoxycyclope
ntadienylide. Subsequent cross-coupling with 9-iodoanthracene (76%) an
d addition of benzyne (52%) gave yclopentadienyl)(tetraphenylcyclobuta
diene)cobalt, the first example of a metallocene containing molecular
gear. (C) 1997 Elsevier Science Ltd.