PHOTOPHYSICS OF MAIN-CHAIN POLYCHROMOPHORES PREPARED BY ACYCLIC DIENEMETATHESIS POLYMERIZATION

A series of bis(vinylthienyl)silane monomers were prepared by reaction of 2 equiv of (vinylthienyl)lithium or (vinylthienyl)magnesium bromid e with different dichlorosilicon dialkyls. The monomers react with the Schrock initiator Mo(NAr)(CHCMe2Ph)(OCMe(CF3)(2))(2) (Ar = 2,6-diisop ropylphenyl), via the acyclic diene metathesis polymerization (ADMET) mechanism, to give poly(silanyl-dithienylethene) derivatives in excell ent yield. GPC data suggest that the resulting polymers have short rep eat sequences. Interchromophore cooperativity is evident, as a low ene rgy emission, for polymer structures that have smaller side groups. Th is phenomenon is similar to the chromophore cooperativity observed in polymers containing stilbene fragments along the backbone.