Oligomers and polymers of thiophene derivatives were synthesized in the channels of
zeolite Y and mordenite. Intrazeolite oxidation of monomers such as thiophene , 3-
methylthiophene , and bithiophene by Fe(lll) or Cu(ll) ions results in formation of insoluble
polymers that have spectroscopic properties similar to the corresponding bulk polymers. The
zeolites containing the polymers are nonconducting, but when extracted from the host, the
polymers show d.c. conductivities typical for t he bulk materials. Oligothiophene species with welldefined
electronic transitions could be produced in acidic zeolite Y