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Our interest in the synthesis of macrocyclic vinyl polymers for energy transfer studies has prompted us to investigate the anionic polymerization of 2-vinylnaphthalene (2VN) and its suitability with regard to the end-to-end coupling of poly2VN dianions with difunctional electrophiles. Polymerizations of 2VN were initiated with t-BuLi and with the lithium and potassium naphthalene radical anions in THF at various temperatures. Generally, rapid polymerizations (<1sec) are observed in all cases. MW distributions were found to be relatively narrow (<1.30) at -780C for the t-BuLi and potassium naphthalenide solutions. The MW distributions broaden considerably above -780C. End-functionalization reactions with TMS-Cl at high initiator concentrations (>10-2M) tend to be quantitative even upon standing for about 1 hour at -780C. However, coupling with difunctional electrophiles is not quantitative, indicating side reactions that most likely involve an intramolecular nucleophilic attack of the 2-naphthyl anion on the penultimate naphthyl ring. Preliminary polymerizations in less polar THF/toluene (1/3, v/v) solutions showed that MW distributions are much narrower (<1.10) and coupling reactions are nearly quantitative. |