LIVING METATHESIS POLYMERIZATION OF [ORTHO-(TRIFLUOROMETHYL)PHENYL]ACETYLENE BY MOLYBDENUM-BASED 3-COMPONENT CATALYSTS

Living metathesis polymerization of [omicron-(trifluoromethyl)phenyl]acetylene, a phenylacetylene with an electron-withdrawing group, has been achieved by using molybdenum-based three-component catalysts. Thus polymerization by MoOCl4-n-Bu4Sn-EtOH (1:1:0.5 mole ratio) catalyst in toluene at 30-degrees-C produced a polymer having a narrow molecular weight distribution; M(w)BAR/M(n)BAR = 1.06. Upon three consecutive additions of fresh monomer feeds to completely polymerized systems, the M(n)BAR of the polymer increased in direct proportion to monomer conversion, while the M(w)BAR/M(n)BAR remained < 1.1. The initiator efficiency was ca. 0.10. The MoCl5-n-Bu4Sn-EtOH (1:1:0.5) catalyst also induced living polymerization, though the M(w)BAR/M(n)BAR (ca. 1.20) was somewhat larger. Effects of catalyst components and polymerization conditions have been studied.