2471-88-7Relevant articles and documents
High Anionic Polymerizability of Benzofulvene: New Exo-Methylene Hydrocarbon Monomer
Kosaka, Yuki,Kawauchi, Susumu,Goseki, Raita,Ishizone, Takashi
, p. 4421 - 4430 (2015/07/28)
The anionic polymerization of benzofulvene (BF) quantitatively proceeded with various initiators, such as sec-BuLi, diphenylmethyllithium, diphenylmethylpotassium, triphenylmethyllithium, and triphenylmethylpotassium, in THF at -78 °C to give polymers having predicted molecular weights based on the molar ratios between BF and the initiators and narrow molecular weight distributions (MWD, Mw/Mn 1H and 13C NMR analyses revealed that the repeating units of poly(BF) consisted of a 1,2-addition unit and a 1,4-addition unit without a 3,4-addition unit regardless of the polymerization conditions. The exo-methylene moiety (CH2=) of BF always participated in the addition polymerization. The addition modes were dependent on the polymerization temperature and not on the solvent or the countercation of the anionic initiator. For instance, polymer obtained with sec-BuLi in THF at 40°C contained 72% of the 1,4-addition unit and 28% of the 1,2-addition unit. Therefore, BF acted as a polymerizable 1,3-diene possessing a fixed transoid framework.