| Co-Investigator(Kenkyū-buntansha) |
HABA Osamu Hokkaido Univ., Fac. of Eng., Instructor, 工学部分子化学専攻, 助手 (70261328)
HASHIMOTO Hisaho Tomakomai National College of Technology, Assoc. Professor, 工業化学科, 助教授 (70180833)
KAKUCHI Toyoji Hokkaido Univ., Grad. School. of Env. Earth., Assoc. Professor, 大学院地球環境科学研究科, 助教授 (80113538)
|
|---|
| Research Abstract |
(1) Molecular recognition of biological receptors and enzymes is concerned with their constitutional and stereochemical features. In order to use synthetic polymers for such a purpose, a recognizable structure must be more elaborately constructed. Therefore, the stereochemical control of polymer chains, in addition to the structural design of functional groups, is desired. Stereospecific polymerization, especially, asymmetric polymerization, affords one means to this end.
(2) Cyclopolymerization which is a facile method for preparing polymers with crown-like units can be used for preparing chiral polymeric crown ethers. The templates with a chiral twist are useful for constructing chiral crown ether units. Under the strategy the cyclopolymerization was developed into one of useful means for asymmetric polymerization.
(3) Regardless of configuration in the B unit, when the diad sequence A-A is a racemo configuration, the triad sequence A-A-B becomes chiral in a copolymer. This phenomenon was synthetically realized by cyclocopolymerization. Bis (p-vinylbenzoate) derivatives of chiral diol templates were copolymerized with stirene. After removal of chiral template and treatment with diazomethane, the resulting methylated polymers were optically active. The chirality of copolymers was inverted before and after hydrolysis. The templates, therefore, transmitted their chirality to the main chain in the intramolecular cyclization to form an enantiomeric racemo cyclic units.
(4) Cyclopolymerization of chiral diepoxides was one of useful means for preparing chiral polymeric crown ethers When used anhydro sugars as a chiral diepoxide monomer, the cyclopolymerization presented a new preparative method for synthetic polysaccharides. The cyclopolymerization of the diepoxy derivatives of hexitols proceeded through the regio-and stereoselective mechanism to form (1*6) -bonded polysaccharides.
|
