Electrochemical dehydrodimerisation of a vinylenylamide ligand: Formation of the binuclear group Mo≡N+CH=CHCH=CHCH=CHN+≡Mo which displays very strong electronic coupling in the (MoIII)-(MoIV) mixed-valence state
Résumé
Electrochemical dehydrodimerisation of an _Mo-N=CHCH=CH2_ group gives an all-trans-_≡N+CH=CHCH=CHCH=CHN+≡_ ligand, bridging two MoIV centres; the ₍MoIII)-bridge-(MoIV)) mixed-valence state is accessible by electrochemical reduction and exhibits very strong electronic coupling over the 11.7 Å which separates the two metal centres; this accords with EHMO calculations which show that the SOMO has substantial (30%) bridging-ligand character; in its capacity to function as a molecular wire linking two metal centres, the eight-atom hexatriene di(imide) chain (N(CH)6NJ compares favourably with C8 chains of acetylenic carbons bridging other metal centres.