Synthesis of chiral polymers containing the acetoxybornyl group and their applications on the asymmetric induction
โ Scribed by Jui-Hsiang Liu; Jue-Cheng Kuo; Mau-Ching Fang
- Publisher
- John Wiley and Sons
- Year
- 1992
- Tongue
- English
- Weight
- 471 KB
- Volume
- 45
- Category
- Article
- ISSN
- 0021-8995
No coin nor oath required. For personal study only.
โฆ Synopsis
Optically active 2-endo-actoxy-5-endo-bornyl methacrylate ( ABMA) was prepared from (+) -camphor. The homopolymerization of ABMA and copolymerization of ABMA with achiral methyl methacrylate (MMA) or styrene (St) were carried out with 2,2'-azobisisobutyronitrile (AIBN) in benzene. Effects of temperature, solvents, and reaction time on the copolymerization were discussed. The monomer reactivity ratios ( rl, r z ) for poly (ABMAco-MMA) and poly(ABMA-co-St) and Q and e values for the chiral ABMA in the copolymerization systems were evaluated by the Fineman-Ross method. The absolute value of the specific rotation of poly ( ABMA-co-MMA) increased with increasing ABMA unit content. A small deviation from linearity was observed, which suggests that asymmetry is not introduced into the copolymer main chain. Temperature and solvent effects on the specific rotation of the chiral homopolymer and copolymers were investigated. The results suggest that the chiral polymers synthesized in this investigation did not show a strong preference for a particular helical conformation. Applications of the chiral polymers on the asymmetric addition of n -butyllithium to aldehydes were also discussed.
๐ SIMILAR VOLUMES
Two generally applicable routes for the synthesis of chiral amino alcohols embodying the bispidine framework have been developed. In linear route A the bispidine framework is built up successively from chiral primary amines via intermediate formation of a piperidinone and a bispidinone. In convergen