Ferrocene donor group complexes

Malacea R, Routaboul L, Manoury E, Daran J-C, Poli R (2008) Palladium and platinum complexes with planar chiral 1,2-disubstituted ferrocenes contairring phosphine and thioether donor groups. J Organomet Chem 693 1469... 

Two basic approaches have been taken. The first consists in grafting organometallic donor and acceptor groups, such as ferrocene [as in [84] (Calabrese et al, 1991)] ruthenium derivatives [as in [83] (Whittall et al, 1996)] and tungsten carbonyl, instead of their organic counterparts on tt-conjugated chains. Quite successful in this respect, although not truly org nometallic, are zwitterions based on borate donors and ammonium acceptors [86] (Lambert et ah, 1996) and Lewis acid complexation as in [85] (Kammler et al, 1996). 

In the simplest case of a donor-acceptor (D-A) molecule, the nonlinear optical activity arises from the electric-field-induced mixing of electronic states such as D-A and D+-A . This makes the response (polarizability) of the molecule different according to the sense of the electric field, and a second-order hyperpolarizability fi coefficient) is observed. If D and A are connected by some bridge, its role in promoting the electronic interaction will be quite similar to the bridge role in mixed-valence complexes. Metal complexes can play the role of donor or acceptor groups. Recent examples have been described with ferrocene or ruthenium(pentaammine) groups [48], but they are either monometallic or too short to be considered in this review. 

Several ferrocenes differing in their degree of methylation have been used for the preparation of conducting 1 2 CT complexes with the organic polycyclic acceptors PTCI and TCIDBT (see Scheme 8-2) [38 a]. Table 8-4 shows pertinent conductivity data for polycrystalline samples at room temperature as a function of the number of methyl groups present in the donor molecule. 

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