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570518 
Journal Article 
Synthesis and structure of the diynyl complexes [Mo(CCCCR)L2([eta]-C7H7)], L2 = chelate N- or P-donor ligand, R = SiMe3 or H: X-ray crystal structures of [Mo(CCCCSiMe3)(2,2'-bipyridine)([eta]-C7H7)] and [Mo(CCCCH)(Ph2PCH2CH2PPh2)([eta]-C7H7)] 
Lancashire, HN; Ahmed, R; Hague, TL; Helliwell, M; Hopgood, GA; Sharp, L; Whiteley, MW 
2006 
Yes 
Journal of Organometallic Chemistry
ISSN: 0022-328X
EISSN: 1872-8561 
691 
17 
3617-3626 
The reaction of LiCCCCSiMe3 with [MoBr(N-N)([eta]-C7H7)] in thf affords the diynyl complexes [Mo(CCCCSiMe3)(N-N)([eta]-C7H7)], [1, N-N = 2,2'-bipyridine (bipy); 2, N-N=1,4--1,3-diazabutadiene (But-dab)]; an analogous procedure yields [Mo(CCCCSiMe3)(CO)(PPh3)([eta]-C7H7)], 3 starting from [MoBr(CO)(PPh3)([eta]-C7H7)]. Replacement of bipy in complex 1 with Ph2PCH2CH2PPh2 (dppe) in refluxing toluene gives [Mo(CCCCSiMe3)(dppe)([eta]-C7H7)], 4. Proto-desilylation of 2 and 4 leads to formation of the unsubstituted diynyls [Mo(CCCCH)L2([eta]-C7H7)] (5, L2 = But-dab; 6, L2 = dppe). Cyclic-voltammetric studies in CH2Cl2 reveal that each of complexes 1, 2 and 4-6 undergo reversible one-electron oxidation processes on the electrochemical time-scale. The X-ray crystal structures of complexes 1 and 6 are reported; the bipyridine complex 1, exhibits a [pi]-[pi] stacking interaction between the bipy ligands of adjacent molecules leading to a head-to-head interaction between diynyl ligands and a resultant substantial bending of the diynyl chain. 
Diynyl ligand; Molybdenum; Cycloheptatrienyl; Electrochemistry