• Journal of the Korean Chemical Society
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• v.48 no.5
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• pp.473-482
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• 2004

The homobimetallic anion, $M^+({\eta}^5-MeCp)Mn(CO)_2Mn(CO)_5^-(M^+=Na^+,\;PPN^+)$was disrupted by CH2CHCH2Cl in THF at various temperatures ($20^{\circ}C~50^{\circ}C$) under the pseudo 1st order reaction conditions where excess of allyl chloride was employed under a nitrogen atmosphere. This homobimetallic anion seems to be involved in a concerted reaction mechanism in which a four-centered transition state is proposed. After undergoing the transition state, this reaction eventually leads to (MeCp)Mn$(CO)_3$ on addition of CO and $({\eta}^1-allyl)Mn(CO)_5$, respectively. However, in case of $Na^+$ analog, $Na^+$ may play a novel counter ion effect on the disruption reaction either by transferring one terminal CO from the $Mn(CO)_5$ moiety on to the $({\eta}^5-MeCp)Mn(CO)_2$of the corresponding homobimetallic complex, eventually resulting in $({\eta}^5-MeCp)Mn(CO)_3$ or through the interaction between $Na^+$ and the leaving group (Cl) of allyl chloride. This reaction is of overall second order with respect to homobimetallic complex with the activation parameters (${\Delta}H^{\neq}=17.15{\pm}0.17kcal/mol,\;{\Delta}S^{\neq}=-9.63{\pm}0.10$ e.u. for $Na^+$ analog; ${\Delta}H^{\neq}=22.13{\pm}0.21 kcal/mol,\;{\Delta}S^{\neq}=9.74{\pm}0.19$ e.u. for $PPN^+$ analog reaction).

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3771-3776
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• 2013

1-Alkyl-3-methylimidazolium chloride-LiCl melts were prepared from the reaction of 1-alkyl-3-methylimidazolium chloride ([RMIm]Cl; R=allyl or n-butyl) and lithium chloride, and their ability to dissolve cellulose was evaluated. The solubility of cellulose was greatly increased to 320% when [RMIm]Cl was replaced by [RMIm][$LiCl_2$]. Dissolved cellulose in LiCl/[RMIm]Cl melts was successfully regenerated by adding water and LiCl/[RMIm]Cl melts were easily recovered by removing water. As supported by the computational results, the higher solubility of cellulose in [RMIm][$LiCl_2$] can be ascribed to the increased bond distance between anion and C(2)-H of the imidazolium ring compared with that in [RMIm]Cl, thereby resulting in the increased interaction between $[LiCl_2]^-$ and the hydroxyl groups of cellulose.

• YAKHAK HOEJI
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• v.58 no.1
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• pp.28-32
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• 2014

A new series of 3-allylthio-6-alkylthiopyridazines (3)~(12) was synthesized from dichloropyridazine (1) for development of candidates to retain anticancer activity of human breast cancer. The process involves allythiolation and alkylthiolation from 3,6-dichloropyridazine. 6-Substituted allylthiopyridazines (3)~(12) were prepared from 3-allylthiopyridazinyl chloride (2) via nucleophilic substitution with alkylthiol anion as nucleophile. 3-Allylthiopyridazinyl chloride (2) could be converted to pyridazines (3)~(11) using 1 equivalent of alkyl mercaptan at reflux temperature in methanol. 3,6-Diallylthiopyridazine (12) was synthesized from 3,6-dichloropyridazine (1) using allyl mercaptan (4 equivalent) and sodium hydroxide in methanol. Synthetic compounds were fully identified using NMR, IR, GC-MS data.

• Bulletin of the Korean Chemical Society
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• v.10 no.3
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• pp.262-269
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• 1989

The gas phase thermal decomposition of 1-bromo-3-chloropropane in the presence of radical inhibitor was studied by using the conventional static system. The mechanism of unimolecular elimination channel is shown below. [...] In this scheme, the total molecular dissociation rate constant, ($k_1\;+\;k_2$), for the decomposition of $BrCH_2CH_2CH_2Cl$ was determined by pyrolyzing the $BrCH_2CH_2CH_2Cl$ in the temperature range of $380-420^{\circ}C$ and in the pressure range of 10∼100 torr. To obtain $k_3\;and\;k_4,\;and\;to\;obtain\;k_1\;and\;k_2$ independently, the thermal decompositions of allyl chloride and allyl bromide were also studied. The Arrhenius parameters for each step are as follows; $log\;A_{\infty}\;=\;14.20(sec^{-1}),\;E_a$ = 56.10(kcal/mol) for reaction path 1; $log\;A_{\infty}\;=\;12.54(sec^{-1}),\;E_a$ = 49.75(kcal/mol) for reaction path 2; $log\;A_{\infty}\;=\;13.41(sec^{-1}),\;E_a$ = 50.04(kcal/mol) for reaction path 3; $log\;A_{\infty}\;=\;12.43(sec^{-1}),\;E_a$ = 52.78(kcal/mol) for reaction path 4; Finally, the experimentally observed pressure dependence of the rate constants in each step is compared with the theoretically predicted values that are obtained by the RRKM calculations.

• Journal of the Korean Chemical Society
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• v.37 no.1
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• pp.136-140
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• 1993

New synthetic method for diethyl N-[4-{[(2,4-diamino-6-yl)methyl]-amino}benzoyl]-L-glutamate(10) which is an intermediate of methotrexate is described. p-Nitrobenzoyl-L-glutamate was obtained via a two-step sequence which involves condensation of p-nitrobenzoyl chloride with diethyl-L-glutamate and Fischer esterification reaction with ethanol. Reductive methylation of diethyl-p-nitrobenzoyl-L-glutamate were carried out by reaction with formic acid and paraformaldehyde in the presence of $PtO_2$ catalyst and yielded diethyl N-(4-methylaminobenzoyl)-L-glutamate(7). It was followed by allylation and iodoazidozation to give the diethyl-p-[N-(2-azido-3-iodopropyl)-N-methyl]aminobenzoyl-L-glutamate(9). The cyclization reaction of compound(9) with 2,4,5,6-tetraaminopyrimidine was carried out by intermolecular nucleophilic substitution to give the desired methotrexate diethylester.

• Bulletin of the Korean Chemical Society
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• v.18 no.8
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• pp.824-827
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• 1997

Bis(ethylene)rhodium(Ⅰ) chloride dimer reacted with vinylcyclopropane to give σ,η3-allylrhodium(Ⅲ) complex 3. Complex 3 underwent C-C bond cleavage of 8-quinolinyl ethyl ketone 11, to form η3-1,3-dimethylallylrhodium(Ⅲ) complex 8, which was reductively eliminated by trimethyl phosphite to give 8-quinolinyl-1-methylbut-2-enyl ketone (10). More sterically hindered 8-quinolinyl alkyl ketones were allowed to react with complex 3 to afford corresponding alkenes as well as a mixture of complex 8 and η3-1-ethylallyl rhodium(Ⅲ) complex 19, identified as 10 and 8-quinolinyl-pent-2-enyl ketone (20) after reductive elimination. 8-Quinolinyl alkyl ketone bearing a sterically hindered alkyl group showed less reactivity for C-C bond cleavage and higher 20/10 ratio compared with those having a less sterically hindered alkyl group, such as 8-quinolinyl ethyl ketone (11).

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.2
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• pp.56-65
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• 2013

Electron beam treatment was applied for improving dissolution of cellulose with ionic liquids. Two ionic liquids, 1-allyl-3-methylimidazolium chloride ([Amim]Cl]: AC) and 1,3-dimethylimidazolium methylphosphite ([Dmim][$(MeO)(H)PO_2$]: Me) were used for this experiment. Treatment with electron beams up to dose of 400 kGy resulted in the increase of hot water extract and alkali extract of cotton pulp and the great reduction in the molecular weight of cellulose. For the dissolution of cotton pulp with two ionic liquids, the electron beam treated samples showed faster dissolution. The dissolved cellulose with Me ionic liquid were regenerated with acetonitrile and the structure of regenerated cellulose showed distinct difference depending on the electron beam treatment. Those results provide the electron beam pre-treatment could be applied as an energy efficient and environmentally benign method to increase the dissolution of cellulose with ionic liquids.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11b
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• pp.34-42
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• 1999

The present investigation has focused up on the study of the adsorption of three different molecular mass fractions of a polyDiMethylDiAllylAmmoniumChloride (DMDAAC) (8750(LM\ulcorner), 48000(MM\ulcorner) and 1200000(HM\ulcorner)) on bleached chemical fibres. Both kinetics of adsorption and equilibrium adsorption measurements have been conducted and each adsorption has been measured by polyelectrolyte titration. The results show that the LM\ulcorner polymer can reach all of the charges in the fibre wall whereas the MM\ulcorner and HM\ulcorner can only reach the external surfaces of the fibres. It is also shown that the kinetics of adsorption of the LMw polymer is not at all affected by the presence of a saturated layer of HMw polymer on the surface of the fibres. Finally, the results from the investigation show that it is possible to have full coverage of the external surface of the fibres by a high molecular mass polymer and a full coverage of the internal surface of the fibres with a low molecular mass polymer. This is true if the high molecular masspolymer is added first followed by addition of the low molecular masspolymer.

• Journal of the Korean Chemical Society
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• v.34 no.6
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• pp.534-538
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• 1990

Chromium(Ⅵ) compound, [$C_9H_7$NH]$_2Cr_2O_7$ has been prepared by the reaction of isoquinoline with chromium trioxide under the presence of water. [$C_9H_7$NH]$_2Cr_2O_7$ is nonhydroscopic and dissolved in water very well. Structure of [$C_9H_7$NH]$_2Cr_2O_7$ is identified by FTIR spectra and elemental analysis data. The ability of [$C_9H_7$NH]$_2Cr_2O_7$ for the oxidation of alcohols were examined in methylene chloride. [$C_9H_7$NH]$_2Cr_2O_7$ was found as efficient oxidizing agent for the conversion of allyl, primary and secondary alcohols to the corresponding aldehydes or ketones.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.4122-4126
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• 2012

Cellulose-graft-poly (L-lactide) (cellulose-g-PLLA) was successfully prepared via ring-opening polymerization (ROP) by using 4-dimethylaminopyridine (DMAP) as an organic catalyst in an ionic liquid 1-allyl-3-methylimidazolium chloride (AmimCl). The structure and morphology of the polymer was characterized by nuclear magnetic resonance (NMR) and transmission electron microscope (TEM). From wide-angle X-ray powder diffraction (WAXD) and degradation test (by acid, alkaline, PBS and enzyme solution), changes in the crystalline structure as a result of degradation was also investigated. The results indicated that materials which have low degree of crystallinity showing higher degradability, however, in acid liquor, enzyme solution, alkaline liquor and PBS system, the degradation rate of the polymer decreased by the above sequence. Moreover, with the further increase of graft degree of this material, its degradation degree decreased.