Homoannular polymetallocenes

There has also been considerable interest directed toward the synthesis of conjugated polymetallocenes due to the electronic communication that these materials may possess. Many polymetallocenes were produced via polycondensation reactions of I,l -disubstituted metallocenes. More rare are examples that describe the polycondensation of 1.3-disubstituted metallocenes. The synthesis of an optically active homoannularly substituted conjugatedpolyferrocene 7 was recently reported by Plenio and coworkers. 

Research in metallocene-containing polyamides, polyureas, polyuretiianes, and polyesters continued to be conducted in the 1980s, and since that time, research into these classes of materials has continued to grow7 Homoannular and heteroaimular liquid-crystalline polymetallocenes have been prepared by Zentel and coworkers through condensation reactions. Ferrocene-based liquid-crystalline polymers have also been reported by Senthil and Kannan. The synthesis of ferrocene polymers containing backbone organophosphorus moieties 32 is shown in scheme 9. 

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