Polycarbostannanes have been successfully synthesized via acyclic dien
e metathesis chemistry utilizing both a well-defined molybdenum akylid
ene and an aryloxo tungsten ''classical'' catalyst system. In the case
of the well-defined catalyst, the polymerization proceeds smoothly to
produce linear polymer which is characterized by proton, carbon, and
tin NMR. Molecular weights of about 16000 g/mol can be produced. The p
roduction of a polycarbostannane via classical metathesis chemistry is
just as facile, producing molecular weights comparable to the well-de
fined system, and in this case, the monomer performs as both the monom
er and the cocatalyst species.