422318-59-0Relevant articles and documents
Novel palladium(0)-catalyzed polyaddition of bifunctional vinyloxiranes with 1,3-diketones. Synthesis of new polymers bearing an allyl alcohol moiety via π-allylpalladium intermediates
Koizumi, Toshio,Sakamoto, Jun,Gondo, Yasuhiko,Endo, Takeshi
, p. 2898 - 2902 (2007/10/03)
Palladium(0)-catalyzed polyaddition of bifunctional vinyloxiranes [1,4-bis(2-vinylepoxyethyl)benzene (6a) and 1,4-bis(1-methyl-2-vinylepoxyethyl)benzene (6b)] with 1,3-diketones [acetylacetone (2) and 1,3-indandione (8)] as carbon nucleophiles afforded new polymers having an allyl alcohol moiety in the main chain and ketone groups in the side groups. The molecular weights of polymers obtained from 6b were higher than those of polymers from 6a. It was suggested that the cause of formation of lower molecular weight polymers from 6a is the β-hydrogen elimination of the π-allylpalladium intermediate generated by oxidative addition of Pd(0) to 6a. The Pd(0)-catalyzed polyaddition of 6b and 2 gave the corresponding polymer 7b (Mn 9800) when Pd2(dba)3·CHCl3/dppf (dba, dibenzylideneacetone; dppf, 1,2-bis(diphenylphosphino)ferrocene) was used as a catalyst. By use of Pd(PPh3)4, the polyaddition of 6b and 8 afforded the desired polymer 9b with high molecular weight (Mn 67 600). The stereochemistries of all of the obtained polymers were confirmed as being in the E-configuration by the coupling constant of the vinyl proton (-C(OH)CH=CHCH2-); the J values were in the range 14.5-15.1. The Z-isomers were observed neither in the 13C NMR spectra nor in the 1H NMR spectra.