The Vinyl Reactivity of (Eta (5)-Vinylcyclopentadienyl) Dicarbonylnitrosylchromium. A Novel Vinyl Organometallic Monomer.

摘要

The novel vinyl organometallic monomer (eta(5)-vinylcyclopentadienyl) dicarbonylnitrosylchromium (hereafter called vinylcynichrodene), recently prepared, was homopolymerized and copolymerized in the presence of azo initiators, both neat and in benzene solutions. Reactivity ratios were obtained in radical-initiated copolymerizations with styrene and N-vinyl-2-pyrrolidone. The resonance interaction parameter Q was 3.1 for vinylcynichrodene. Copolymerizations with N-vinyl-2-pyrrolidone (M2) gave r1 - 5.3, r2 = 0.079 and e1 = -2.07. Thus, it is clear that vinylcynichrodene is an exceptionally electron-rich vinyl monomer resembling vinylferrocene and vinylcymantrene. Vinylcynichrodene readily copolymerized with vinylcymantrene and homopolymerized in high yields in ethyl acetate solution. The molecular weight of poly(vinylcynichrodene) increased as the monomer to initiator ratio increased suggesting that the rate was not first order in initiator as had been found previously in vinylferrocene polymerizations.