Inverse Phase Transfer Catalysis --- Pyridine 1- oxide- Catalyzed Two-Phase Reaction of Benzoyl Chloride and Carboxylates

• Main Authors: Ou, Chin-Chou, 歐錦綢
• Other Authors: Wang Maw-Ling;Jwo Jing-Jer
• Format: Others
• Language: zh-TW
• Published: 1994
• Online Access: http://ndltd.ncl.edu.tw/handle/11340725008615959065

博士 === 國立清華大學 === 化學工程研究所 === 83 === In this dissertation, the reaction of benzoyl chloride (PhCOCl) and carboxylates in a two-phase water/dichloromethane medium was studied using pyridine 1-oxide (PNO) as an inverse phase trans- fer catalyst. The main goal of this study is to investigate the effects of (I) carboxylate ions , (II) dicarboxylate ions, (III) solvent, (IV) dis- tribution of PNO, (V) amino carboxylate ions and (VI) mixed catalyst. The main conclusions are su- mmarized as follows: 1.Beyond 1100rpm , the reaction rate is independ- ent of the agitation rate . 2.Under appropriate conditions , the reaction of PhCOCl and PNO in dichloromethane producing the intermediate is a rate- determining step. 3.The uncatalyzed two-phase reaction of PhCOCl and carboxylates (or dicarboxylates) is slow and with benzoic acid as the main product. 4.In the PNO-catalyzed reaction of PhCOCl and RCOONa, the yield of acid anhydride (PhCOOCOR) was generally about 80-90 % . 5.In the PNO-catalyzed reaction of PhCOCl with di- carboxylates, the composition of products depends strongly on the property of dicarboxylate. 6.The distribution of free PNO in the organic ph- ase is affected by PhCOCl, carboxylates, solvent and temperature. 7.Two-phase equilibrium reaction is observed in the PNO- catalyzed reaction of PhCOCl and butano- ate ion or of butanoyl chloride and benzoate ion. 8.The uncatalyzed reaction of PhCOCl and amino acid is very fast and produces amide with yield higher than 95 %. The presence of PNO or 4-dime- thylaminopyridine enhances the rate of reaction significantly . 9.The order of efficiency of catalysis is inverse phase transfer (IPT) catalyst >> normal phase transfer (NPT) catalyst. The mixed NPT and IPT catalysts exhibit additive effect .