KAMIYAMA Hiroteru Cosmo Research Institute, Chemical Technology Laboratory, Genenral Manager, 化学技術研究所, 所長
WAKEJIMA Ikuko Science University of Tokyo, Faculty of Engineering, Lecturer, 工学部, 講師 (00084385)
|Budget Amount *help
¥10,000,000 (Direct Cost : ¥10,000,000)
Fiscal Year 1995 : ¥1,500,000 (Direct Cost : ¥1,500,000)
Fiscal Year 1994 : ¥1,800,000 (Direct Cost : ¥1,800,000)
Fiscal Year 1993 : ¥6,700,000 (Direct Cost : ¥6,700,000)
1.2, 6-Naphthalenedicarboxylic acid (2, 6-NDA) is a useful intermediate for the syntheses of high performance polymers and liquid crystalline compounds. Poly (ethylene 2, 6-naphthalene-dicarboxylate) is superior to poly (ethylene terephthalate) in mechanical properties, thermostability and gas-barrier ability of films. The synthesis of 2, 6-NDA was attempted by oxudation of 2, 6-dialkylnaphthalene, and by oxidation of 2-alky-6-acylnaphthalene. We reported preliminarily the selective carboxylation of 2-naphthalenecarboxylic acid using beta-cyclodextrin (beta-CyD) as catalyst. The present research has been carried out to search the optimum conditions for the selective synthesis of 2, 6-NDA from 2-naphthalenecarboxylic acid, carbon tetrachloride and copper powder in aqueous alkali by the use of beta-CyD.
2. The yield of 2, 6-NDA increased with increasing amounts of beta-CyD, and took a maximum (39 mol% with 78% selectivity) at the initial mole ratio of beta-CyD to 2-naphtalenecarboxylic ac
id of 1.0, where the 2, 7-DNA and 1, 6-NDA were 9.1 mol% and 1.7mol%, respectivelv. When alpha-CyD or gamma-CyD was used instead of beta-CyD, the reaction hardly proceeded.
3. The yield of 2, 6-NDA increased with increasing amounts of carbon tetrachloride, and had a maximal value (58 mol% with 83% selectivity) at the initial mole ratio of carbon tetrachloride to 2-naphthalenecarboxylic acid of 5.0. The efficient addition of carbon tetrachloride was affempted. The reaction was started with the addition of 0.6 mmol of carbon tetrachloride to the aqueous sodium hydroxide solution containing 2-naphthalenecarboxylic acid, beta-CyD and copper powder, and was continued for 8 h by adding 0.6 mmol or carbon tetrachloride to the reaction mixture at 15 min intervals. The resulting yields of 2, 6-NDA was 67 mol% with 84% selectivity.
4. The conformation of beta-CyD-2-naphthalenecarboxylate inclusion complex in aqueous alkali was determined by the nuclear magnetic resonance spectroscopy using ^1H homonuclear Overhauser enhancement on the rotating frame. The very high selectivity was ascribed to the conformation of the beta-CyD-2-naphthalenecarboxylate inclusion complex. Less