• Proceedings of the Korean Society of Rheology Conference
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• 2002.05a
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• pp.29-32
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• 2002

• Journal of the Korean Chemical Society
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• v.34 no.6
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• pp.676-679
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• 1990

• Journal of Integrative Natural Science
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• v.8 no.4
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• pp.235-243
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• 2015

Rhodium(I)-complex of $[Rh(CO)_2I_2{^-}]$ catalyzed carbonylation of anhydrous-trimethylamine in the presence of methyl iodide to give DMAC (N,N-dimethylacetamide) in no solvent. The catalyst had been reused 20 times, the analyses and distillation of collected products showed that the yields of DMAC, MAA (N-methylacetamide), and DMF (N,N-dimethylformamide) were 82.3%, 12.6%, and 4.4%. The conversion rate of trimethylamine was 99 % and the selectivity of DMAC was 82.3% with TON (Turnover Number) of 700. Stepwise procedure of inner-sphere reductive elimination for the formation of DMAC was suggested instead of acyl iodide intermediate.

• Bulletin of the Korean Chemical Society
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• v.25 no.9
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• pp.1403-1407
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• 2004

Dielectric relaxation measurements on 3-nitrotoluene (3-NT) mixture of dimethylacetamide (DMA), dimethylformamide (DMF) and dimethysulphoxide (DMSO) have been carried out across the entire concentration range using Time domain reflectometry technique at 15, 25, 35 and $45^{\circ}C$ over the frequency range from 10 MHz to 20 GHz. For all the mixtures, only one dielectric loss peak was observed in this frequency range and the relaxation in these mixtures can be well described by a single relaxation time using Debye model. Bilinear calibration method is used to obtain complex permittivity ${\varepsilon}^{*}({\omega})$ from complex reflection coefficient ${\rho}^{*}({\omega})$ over frequency range 10 MHz to 20 GHz. The excess permittivity, excess inverse relaxation time, Kirkwood correlation factor, molar energy of activation are also calculated for these mixtures to study the solute-solvent interaction.

• 월간산업보건
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• s.72
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• pp.2-6
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• 1994

• Korean Chemical Engineering Research
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• v.53 no.5
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• pp.553-556
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• 2015

The usage of the correct combustion characteristic of the treated substance for the safety of the process is critical. For the safe handling of dimethylacetamide (DMAc) being used in various ways in the chemical industry, the flash point and the autoignition temperature (AIT) of DMAc was experimented. And, the lower explosion limit of DMAc was calculated by using the lower flash point obtained in the experiment. The flash points of DMAc by using the Setaflash and Pensky-Martens closed-cup testers measured $61^{\circ}C$ and $65^{\circ}C$, respectively. The flash points of DMAc by using the Tag and Cleveland automatic open cup testers are measured $68^{\circ}C$ and $71^{\circ}C$. The AIT of DMAc by ASTM 659E tester was measured as $347^{\circ}C$. The lower explosion limit by the measured flash point $61^{\circ}C$ was calculated as 1.52 vol%. It was possible to predict lower explosion limit by using the experimental flash point or flash point in the literature.

• The Korean Journal of Malacology
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• v.26 no.4
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• pp.255-260
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• 2010

This study was conducted to investigate protocol standardization for spermatozoa cryopreservation of the Scapharca broughtonii (Schrenck). Among the freezing rates, freezing at a height of 2 cm above liquid nitrogen surface for 5 minute gave higher activity and survival rate. Among the various diluents, Ringer's solution was the best for S. broughtonii sperm cryopreservation. The suitability of cryoprotectants dimethylsulfoxide (DMSO), dimethylacetamide (DMA), glycerol and methanol were tested against three freezing rates. DMSO gave significantly higher activity and survival rates than others.

• 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.

• Journal of the Korean Chemical Society
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• v.31 no.6
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• pp.486-490
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• 1987

The effect of the hydrogen-bonding between thioacetamide (TA) and amides (N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA) and N,N-dimethylpropionamide (DMP)) on the hindered rotation of N-C(S) bond of TA was investigated by the nmr spectroscopy. The $^1H$-nmr spectrum of $NH_2$ group in TA was distinctly separated into two peaks with increasing the amount of $CCl_4$ and the effect of amides on the peak separation was in the order of DMF < DMA < DMP. Those phenomena were interpreted in terms of hydrogen-bonding between TA and amide.

• KSBB Journal
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• v.8 no.3
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• pp.230-236
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• 1993

A Chitulose film was made by dissolving chitin and cellulose in a dimethylacetamide/LiCl solvent system This film was completely degraded in 20 days in soil and penetrated by soil microorganisms in 16-26 hours. A permeability analysis of the film showed that water permeability was in the range of 0-187.5 $1/m^2$/day, depending upon the ratio of chitin to cellulose and decreased with increasing a cellulose content in the Chitulose film The permeabilities of organic compounds, $Na^+$ and oxygen change with the composition of the Chitulose file The film was tested with a burned 2~3degree rat for exploring its use as artificial skin. The rat was completely cured within 31 days without inflammation.