| Summary: | 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 .
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