• Bulletin of the Korean Chemical Society
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• 제5권1호
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• pp.21-23
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• 1984

The addition reactions of thioglycolic acid to ${\omega}$, ${\omega}$-diacetylstyrene derivatives were investigated. ${\omega}$, ${\omega}$-Diacetylstyrene derivatives easily undergo addition reactions with thioglycolic acid to form s-(2, 2-diacetyl-1-phenylethyl)-thiogycolic acid, s-[2,2-diacetyl-1-(methyl) phenylethyl]-thioglycolic acid, s-[2,2-diacetyl-1-(p-methoxy) phenylethyl]-thioglycolic acid and s-[2,2-diacetyl-1-(p-chloro) phenylethyl]-thioglycolic acid, respectively. The structures of these compounds were identified by neutralization equivalent, UV, IR, and NMR spectral data.

• 공업화학
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• 제21권1호
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• pp.93-97
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• 2010

친핵성 첨가반응에 의한 극성 용매(NMP, DMSO, DMF, m-cresol etc.)에 용해성을 갖는 이온성 액체(1,3-dimethylimidazolium methylsulfate, I-DMS)로 도핑된 폴리아닐린(PAN/I-DMS)을 합성하였다. 극성 용매 내에서 PAN/I-DMS의 용해도는 3~6 wt%/vol.을 나타내었고, PAN/I-DMS films의 전기전도도는 $10^{-2}{\sim}7S/cm$를 나타내었다. PAN/I-DMS는 HCl로 도핑된 폴리아닐린(PAN/HCl)과 dimethylsulfate (DMS)로 도핑된 폴리아닐린(PAN/DMS)에 비하여 $160^{\circ}C$에서 열적 안정성과 전기 전도성이 우수함을 볼 수 있었다. 극성 용매 내에서의 용해도와 전기 전도도 증가 현상을 극성 sulfonate group과 극성 용매간의 상호 작용으로 설명하였다.

• 농약과학회지
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• 제8권4호
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• pp.265-271
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• 2004

제초제 flumioxazine의 가수분해 반응성을 분자 궤도(MO)론적으로 검토한 결과, pH 5.0 이하의 산성에서는 $A_{AC}1$형의 반응 메커니즘으로 1,2-dicarboximino group의 carbonyl oxygene 원자$(O_{21})$에 대하여 hydronium ion $(H_3O^+)$에 의한 양성자화$(SH^+)$가 일반 산-촉매반응(general acid catalysis)에 따른 전하조절(charge-control) 반응이 일어난다. pH 8.0이상의 염기성에서는 $B_{AC}2$형의 반응 메커니즘으로 hydroxide anion $(OH^-)$에 의한 특정 염기-촉매반응(specific base catalysis)에 따른 궤도조절(orbital-control) 반응이 일어난다. 그리고 pH $5.0\sim8.0$ 사이에서 두 반응은 경쟁적으로 일어나 친핵성 첨가-제거반응$(Ad_{N-E})$으로 진행된다.

• 대한화학회지
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• 제17권5호
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• pp.363-370
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• 1973

$\alpha$-Cyano-$\beta$-piperonylacrylic acid에 대한 n-Propylmercaptan의 친핵성 첨가반응 속도 상수를 측정하여 넓은 pH 범위에서 잘 맞는 반응속도식을 구하였다. 이 식에 의하면 넓은 pH 범위에서 일어나는 복잡한 반응메카니즘을 정량적으로 잘 설명할 수 있었다. 즉 pH4.5이하에서는 $\alpha$-Cyano-$\beta$-piperonylacrylic acid에 mercaptan이 직접 첨가되며 pH 4.5∼6.5 사이에서는 주로 $\alpha$-Cyano-$\beta$-piperonylacrylic ion에 mercaptan 분자가 첨가되고 pH 7.5 부터는 $\alpha$-Cyano-$\beta$-piperonylacrylic ion에 mercaptan 분자와 mercaptide ion의 첨가가 경쟁적으로 일어나며 pH 10이상에서는 $\alpha$-Cyano-$\beta$-piperonylacrylic anion에 mercaptide ion의 첨가만이 일어남을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3543-3548
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• 2010

A kinetic study on nucleophilic displacement reactions of 2-pyridyl X-substituted benzoates 1a-e with potassium ethoxide (EtOK) in anhydrous ethanol is reported. Plots of pseudo-first-order rate constants ($k_{obsd}$) vs. $[EtOK]_o$ exhibit upward curvature. The $k_{obsd}$ value at a fixed $[EtOK]_o$ decreases steeply upon addition of 18-crown-6-ether (18C6) to the reaction mixture up to [18C6]/$[EtOK]_o$ = 1 and then remains nearly constant thereafter. In contrast, $k_{obsd}$ increases sharply upon addition of LiSCN or KSCN. Dissection of $k_{obsd}$ into $k_{EtO^-}$ and $k_{EtOM}$ has revealed that ion-paired EtOK is more reactive than dissociated $EtO^-$, indicating that $K^+$ ion acts as a Lewis acid catalyst. Hammett plots for the reactions of 1a-e with dissociated $EtO^-$ and ion-paired EtOK result in excellent linear correlation with $\rho$ values of 3.01 and 2.67, respectively. The $k_{EtOK}/k_{EtO^-}$ ratio increases as the substituent X in the benzoyl moiety becomes a stronger electron-donating group. $K^+$ ion has been concluded to catalyze the current reaction by stabilizing the transition state through formation of a 6-membered cyclic complex.

• 한국응용과학기술학회지
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• 제7권2호
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• pp.33-40
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• 1990

The Kinetics of the addition of benzalacetophenone derivatives was investigated by ultraviolet spectrophotometery in 5% dioxane $H_2O$ at $50^{\circ}C$. A rate equation was obtained in wide range of pH. The substituent effects on benzalacetophenone derivatives were studied, and addition were facilitated by electron attracting groups. The final product was benzalacetophenone-${\beta}$-thioglycolic acid synthesized by the addition of thioglycolic acid to benzalacetophenone. On the base of the rate equation, substituent effect, general base effect and final product, the plausible addition mechanism was proposed: Below pH 9.0, only neutral thioglycolic acid molecule was added to the carbon-carbon double bond, and in the range of pH $9.0{\sim}11.0$, neutral thioglycolic acid molecule and thioglycolic acid anion competitively attacted the double bond. By contrast, above pH 11.0, the reaction was dependent upon only the addition of thioglycolic acid anion.

• Bulletin of the Korean Chemical Society
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• 제24권7호
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• pp.921-924
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• 2003

Homochiral (-)-pipecolaldehyde 6 from D-glucono- δ-lactone underwent a highly diastereoselective addition upon treatment with vinylmagnesium bromide. Treatment with vinylmagnesium bromide produced antiaminoalcohol 7a which was easily converted into the synthesis of 1,6-diepicastanospermine 2.

• Bulletin of the Korean Chemical Society
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• 제10권6호
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• pp.500-503
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• 1989

Synthetic studies have been carried out for the addition or substitution of phosphorus nucleophiles to the cation $[(exo-6-R-{\eta}^ {5_-}2-MeO-C_6H_5)Mn(CO)_2NO]PF_6,$ 2. $PPh_3$ reacts with 2 to yield the CO displaced product and $MePPh_2$ attacks the dienyl ring of 2 to yield the phosphonium adduct or the metal to give the CO displaced depending upon the reaction temperatures. Nucleophilic addition of HPPh2 to the dienyl ring of 2 gives a neutral substituted product. $P(OMe)_3$ reacts with 2 to yield a mixture of ring adduct and CO displaced product at room temperature. $At - 20^{\circ}C,\;P(OMe)_3$ attacks the dienyl ring of 2 to give a posphonium adduct, which underwent Arbuzov reaction. This reaction affords a new route to the phosphonate complexes.

• 대한화학회지
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• 제31권4호
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• pp.364-368
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• 1987

${\beta}-Acetyl-{\beta}-benzoylstyrene$ 유도체에 대한 thioglycolic acid, benzenethiol 및 benzylmercaptan의 첨가반응에 관하여 연구하였다. ${\beta}-acetyl-{\beta}-benzoylstyrene$ 유도체는 쉽게 thioglycolic acid, benzenethiol, benzylmercaptan과 반응하여 다섯가지 (2-acetyl-2-benzoyl-1-phenylethyl) thioglycolic acid 유도체 (IIa-IIe), 다섯가지의 (2-acetyl-2-benzoyl-1-phenylethyl)benzenethiol 유도체 (IIIa-IIIe) 및 다섯가지의 (2-acetyl-2-benzoylphenylethyl)benzylmercaptan 유도체 (IVa-IVe)를 합성한다.

• Bulletin of the Korean Chemical Society
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• 제4권2호
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• pp.92-95
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• 1983

The addition products of glutathione to ${\beta}$ -nitrostyrene derivatives were synthesized. ${\beta}$ -Nitrostyrene (1a), p-methyl-${\beta}$-nitrostyrene (1b), 3,4,5-trimethoxy-${\beta}$-nitrostyrene (1c), o-, m- and p-chloro-${\beta}$-nitrostyrene (1e, 1f, 1g) and o-, m- and p-methoxy-${\beta}$-nitrostyrene (1h, 1i, 1j) undergo addition reactions with glutathione to form S-(2-nitro-1-phenylethyl)-L-glutathione (5a), S-[2-nitro-1-(p-methyl)phenylethyl]-L-glutatione (5b), S-[2-nitro-1-(3', 4', 5'-trimethoxy)phenylethyl]-L-glutathione (5c), S-[2-nitro-1-(o-chloro)phenylethyl]-L-glutathione (5e), S-[2-nitro-1-(m-choro)phenylethyl]-L-glutathione (5f), S-[2-nitro-1-(p-chloro)phenylethyl]-L-glutathione (5g), S-[2-nitro-x-(o-methoxy)-phenylethyl]-L-glutathion e(5h), S-[2-nitro-x-(m-methoxy)phenylethyl]-L-glutathion e (5i), and S-[2-nitro-1-(p-methoxy)phenylethy])-L-glutathione (5j), respectively. The structure of adducts were identified by UV and IR-spectra, molecular weight measurement, and elemental analysis.