Get access

Synthesis of optically active alicyclic polyimides from a chiral, nonracemic dianhydride



Optically active alicyclic polyimides were prepared for the first time from (−)-[1S*,5R*,6S*]-3-oxabicyclo[3.2.1]octane-2,4-dione-6-spiro-3′-(tetrahydrofuran- 2′,5′-dione) [(−)-DAn] via polycondensation with diamines and subsequent chemical or thermal imidization. The dianhydride (−)-DAn was synthesized by an asymmetric Diels–Alder reaction of a chiral itaconic acid derivative as a key step. Colorless or slightly yellow flexible films were obtained for the (−)-DAn-derived polyimides {PI[(−)-DAn]s}. PI[(−)-DAn]s showed good solubility toward dipolar aprotic solvents and pyridine. For 1,4-dioxane and chloroform, the optically active polyimides showed slightly better solubility than the corresponding polyimides prepared from rac-DAn [PI(rac-DAn)s]. PI[(−)-DAn]s showed glass-transition temperatures of 267–268 °C and 10% weight-loss temperatures of 416–424 °C in nitrogen. These values were almost identical to those of PI(rac-DAn)s. The circular dichroism spectra of PI[(−)-DAn]s showed exciton coupling patterns indicating that to some extent these polyimides had a higher order structure in solution. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 4038–4044, 2002