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The anionic polymerization of five-membered cyclic carbonates fused to a cyclohexane ring, that is, the trans-and cis-cyclohexane-1,2-diyl carbonates (trans-and cis-1, respectively), were examined as a model polymerization example to reveal the origin of the unusually good polymerizability of the previously reported methyl 4,6-O-benzylidene-2,3-O-carbonyl-a, D-glucopyranoside. The tert-BuOK-initiated anionic polymerization of trans-1 produces polymers with M n values of 11 000, whereas no polymeric products were obtained from cis-1. The structure of the poly(trans-1) was confirmed by comparison with the model carbonate (2) based on the 13 C NMR spectra as well as the hydrolysis experiments. The poly(trans-1) form essentially consists of polycarbonate units; therefore, the polymerization of trans-1 was not accompanied by any decarboxylation. The thermodynamic parameters for the polymerization of trans-1 were estimated to be DH p 1 ¼ À23 kJ mol À1 and DS p 1 ¼ À63 J K À1 mol À1 .

A new dendrimer (1), which contains phenol groups in the exterior for solubilization in aqueous alkaline solution and calix[4]resorcinarene in the interior to increase the molecular weight and number of the phenol group even in the lower generation, was designed as new negative-working, alkaline-developable photoresist material. A negative-working photoresist based on 1, 2,6-bis(hydroxymethyl)phenol as cross-linker, and diphenyliodonium 9,10-dimethoxyanthracene-2-sulfonate as a photoacid generator has been developed. This resist gave a clear negative pattern through postbaking at 110 °C after exposure to UV light, followed by developing with a 0.3% aqueous tetramethylammonium hydroxide solution at room temperature.

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