New photoreactive calixarene derivatives containing cationically polymerizable pendant oxetane groups (calixarenes 1a,b, 2a,b, and 3a,b) were synthesized in good yields by the substitution reaction of C-methylcalix[4]resorcinarene (CRA), p-methylcalix[6]arene (MCA), and p-tert-butylcalix[8]arene (BCA) with (3-methyloxetan-3-yl)methyl 4-toluenesulfonate and (3-ethyloxetan-3-yl)methyl 4-toluenesulfonate with potassium hydroxide as a base and tetrabutylammonium bromide as a phase-transfer catalyst in N-methyl-2-pyrrolidone, respectively. Calixarene derivatives containing cationically polymerizable pendant oxirane groups (calixarenes 4, 5, and 6) were also prepared in good yields by the substitution reaction of CRA, MCA, and BCA with epibromohydrin, respectively, with cesium carbonate as a base in N-methyl-2-pyrrolidone. The thermal stability of the obtained calixarene derivatives containing pendant oxetane groups or oxirane groups was examined with thermogravimetric analysis, and it was found that these calixarene derivatives had thermal stability beyond 340 degreesC. The photochemical reaction of calixarenes 1, 2, and 3 containing pendant oxetane groups was examined with certain photoacid generators in the film state. In this reaction system, calixarene la, composed of a CRA structure and pendant (3-methyloxetan-3-yl)methyl groups, showed the highest photochemical reactivity when bis-[4-(diphenylsulfonio)phenyl]sulfide bis(hexafluorophosphate) was used as the catalyst. The photochemical reaction of calixarenes 4, 5, and 6 containing pendant oxirane groups was also examined, and it was found that the photoinitiated cationic polymerization of calixarenes 4, 5, and 6 proceeded smoothly under the same conditions; however, the reaction rates were lower than those of the corresponding calixarenes 1, 2, and 3 containing pendant oxetane groups. (C) 2001 John Wiley & Sons, Inc.