Synthesis and polymerization of cyclic carbonates containing a binaphthyl moiety

Synthesis and anionic ring-opening polymerization of aromatic cyclic carbonates were investigated. Detailed studies with 2,2'-biphenol and 1,1'-bi(2-naphthol) as diols showed that the synthesis with 2 mol of p-nitrophmyl chloroformate and 2 mol of a tertiary amine afforded the best results (yields of the corresponding cyclic carbonates 3 and 5 were ca. 80%). Preparation using phosgene dimer resulted in good yield of 3 but was not suitable for 5. Stability of 5 was low enough to react with methanol only by mixing to give an adduct readily. High ring-opening ability of 5 based on its strained ring was suggested from the structure simulation of 3 and 5. Anionic ring-opening polymerization of 5 initiated with t-BuOK and the related alkalis proceeded smoothly to give a polycarbonate quantitatively ((M) over bar(n) ca. 15000). This polymer could also be obtained by polycondensation using 1,1'-bi(2-naphthol) and bis(4-nitrophenyl)carbonate. Thermal analysis, powder X-ray analysis, and volume change on polymerization were studied.