CROSS-CONJUGATED POLYMERS VIA CONDENSATION OF A ZIRCONOCENE ALKYNYL(BENZYNE) DERIVATIVE GENERATED BY THERMOLYSIS OF CP(2)ZRME(C6H4C-EQUIVALENT-TO-CSIME(3))

The complex Cp(2)ZrMe(C6H4C=CSiMe(3)) (4) has been synthesized by reac tion of Cp(2)ZrMeCl and LiC6H4C=CSiMe(3) (generated in situ from react ion of (n)BuLi with BrC6H4C=CSiMe(3) at -95 degrees C). Thermolysis of 4 in THF afforded an unsaturated, organometallic polymer [Cp(2)Zr(C6H 3C=CSiMe(3))](n) (7) in ca. 80% yield (M(w)/M(n) = 4000/2000). Polymer 7 was investigated as a synthon for other unsaturated polymers. It re acts with hydrochloric acid to form a new phenylene-1,1-vinylene polym er [-C(=CHSiMe(3))-1,4-C6H4-](n) (8), and with sulfur dichloride to gi ve poly(1-trimethylsilyl-2-benzo[b]thiophene) (9). ?Thermolysis of two similar compounds, Cp(2)ZrMe(C6H4C=CCH3) (5) and Cp(2)ZrMe(C6H4C6H4C= CSiMe(3)) (6), did not give polymers.