The coupling of [3]-ferrocenophan-1-one 1 with McMurry type reagents t
o yield olefins E,Z-bis([3]-ferrocenophane-1-ylidene) 2a,b is describe
d. In the case of the TiCl3/Zn reagent only pinacol rearrangement to c
omplex 3 subsequent to coupling takes place in high yield. In contrast
, upon addition of pyridine the reaction proceeds to the olefins in hi
gh yield. The X-ray structure of 3 and the electrochemistry of the ole
fins 2a,b is described. (C) 1998 Elsevier Science Ltd. All rights rese
rved.