Polymerization of aliphatic alkynes with heterogeneous Mo catalysts supported on mesoporous molecular sieves

Abstract

Aliphatic 1-alkynes were polymerized over heterogeneous catalysts prepared by supporting (i) MoO3 and (ii) Mo (=CHCMe2Ph)(=N-2,6-i-Pr2C6H3)[OCMe(CF3)2]2 on mesoporous molecular sieves MCM-41, MCM-48, and SBA-15. Poly(n-alkylacetylene)s of Mw in the range from 5,000 to 30,000 and poly(tert-butylacetylene) of Mw ∼300,000 were prepared in yields ranging from 11 to 64%. Polyacetylene type structure (conjugated main chain and alkyl pendant groups) was confirmed by 1H NMR. Both catalysts enabled easy product separation delivering polymers free of catalyst residues.