• Bulletin of the Korean Chemical Society
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• v.25 no.3
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• pp.347-348
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• 2004

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.129-134
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• 1999

This study is related to the investigation of the direct incorporation of $CO_2$ to polymer using quaternary ammonium salt catalysts. Quaternary ammonium salts showed good catalytic activity of $CO_2$ fixation in the synthesis of poly[(1,3-dioxolane-2-oxo-4-yl)methyl methacrylate] [poly(DOMA)] by the direct incorporation of $CO_2$ to poly(glycidyl methacrylate)[poly(GMA)]. Among the salts tested, the ones with higher alkyl chain length and with more nucleophilic counter anion showed higher catalytic activity. The yield of carbon dioxide addition increased with the reaction temperature. Kinetic study was carried out by measuring the variation of $CO_2$, pressure in a high pressure batch reactor. The reaction rate was first order to the concentration of poly(GMA) and $CO_2$, respectively. The rate constant was $0.69L/mol{\cdot}h$ and Henry's constant of $CO_2$ in DMSO at $80^{\circ}C$ was $6.8{\times}10^{-4}mol/L{\cdot}KPa$.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2289-2292
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• 2010

Long chain dicationic ammonium salts were used successfully as phase transfer catalyst in the condensation reactions of aromatic aldehydes in water under ultrasonic irradiation for the first time. The quaternary salt having longer distance between the cation centers was more effective than the mono- and dicationic ones having short chain.

• Applied Chemistry for Engineering
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• v.4 no.4
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• pp.715-720
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• 1993

Diphenylmethane (pKa=33.4), which is difficult to be oxidized in normal oxidation conditions, was oxidized to produce benzophenone at ambient temperature and atmospheric pressure by using phase transfer catalysts and solid potassium tert-butoxide as base. Quaternary salt such as benzyltriethylammonium chloride, tetrabutyl ammonium bisulfate, tetrabutylphosponium chloride, are ineffective catalysts for this reaction, but 18-crown-6 and polyethylene glycols showed catalytic activity. The conversion of diphenylmethane was increased with increasing chain length of PEG molecules when they are used as phase transfer catalysts both in equal molar and equal weight basis. The conversion of diphenylmethane was increased with the agitation speed, and aprotic solvent like DMF showed higher reaction rate compared with benzene.

• Journal of Integrative Natural Science
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• v.10 no.4
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• pp.175-191
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• 2017

In organic chemistry amide synthesis is performed through condensation of a carboxylic acid and an amine with releasing one equivalent of water via the corresponding ammonium carboxylate salt. This method is suffering from tedious processes and poor atom-economy due to the adverse thermodynamics of the equilibrium and the high activation barrier for direct coupling of a carboxylic acid and an amine. Most of the chemical approaches to amides formations have been therefore being developed, they are mainly focused on secondary amides. Direct carbonylations of tertiary amines to amides have been an exotic field unresolved, in particular direct carbonylation of trimethylamine in lack of commercial need has been attracted much interests due to the versatile product of N,N-dimethylacetamide in chemical industries and the activation of robust N-C($sp^3$) bond in tertiary amine academically. This review is focused mainly on carbonylation of trimethylamine as one of the typical tertiary amines by transition metals of cobalt, rhodium, platinum, and palladium including the role of methyl iodide as a promoter, the intermediate formation of acyl iodide, the coordination ability of trimethylamine to transition metal catalysts, and any possibility of CO insertion into the bond of Me-N in trimethylamine. In addition reactions of acyl halides as an activated form of acetic acid with amines are reviewed in brief since acyl iodide is suggested as a critical intermediate in those carbonylations of trimethylamine.

• Korean Chemical Engineering Research
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• v.51 no.3
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• pp.347-351
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• 2013

The preparation of glycerol carbonate (GC) from urea through carbonylation with renewable glycerol was investigated by using ionic liquid catalysts. It was found that quaternary ammonium salt and imidazolium salt ionic liquids with a shorter alkyl chain length and higher nucleophilic anion showed better catalytic performance. The effects of reaction temperature, reaction time and degree of vacuum on the reactivity of TBAC catalyst ware discussed. Zinc chloride ($ZnCl_2$) was used as co-catalyst with the ionic liquid catalyst. The mixed catalyst showed a synergy effect on the glycerol conversion and GC yield probably due to the acid-base properties of the catalysts.

• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1156-1163
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• 1996

This study is related to the investigation of the characteristics of quaternary ammonium salt catalyst on the addition reaction of carbon dioxide and glycidyl methacrylate(GMA) to form(2-oxo-1,3-dioxolane-4-yl)methacrylate(DOMA). Among the salts tested, the ones with higher alkyl chain length and with more nucleophilic counter anion showed a higher catalytic activity. Mixed catalysts of NaI and 18-crown-6 showed a good yield of DOMA, but when they are used alone, they showed no catalytic activity. The DOMA monomer was obtained in low polar solvents, while poly(DOMA) could be directly synthesized in aprotic dipolar solvents. Kinetic studies carried out by measuring $CO_2$ pressure in a high pressure batch reactor showed that the reaction rate was first order to the concentration of GMA and $CO_2$ respectively. The rate constant(k) was 0.56L/mol hr and Henry's constant(H') of $CO_2$ in diglyme at $80^{\circ}C$ was $6.5{\times}10^{-4}mol/L{\cdot}kPa$.