• Archives of Pharmacal Research
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• 제14권3호
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• pp.199-203
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• 1991

7H-thiazolo-[3,2-a]-pyridines as potential antimicrobial agents were prepared by reaction of $\alpha,\beta$-unsaturated nitriles and thioglycolic acid.

• Bulletin of the Korean Chemical Society
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• 제14권6호
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• pp.749-752
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• 1993

Borohydride exchange resin $(BER)-CuSO_4$ system readily reduces {\alpha},{\beta}$-unsaturated ketones to the corresponding saturated alcohols quantitatively. This reduction tolerates many functional groups such as carbon-carbon multiple bonds, chlorides, epoxides, esters, amides and nitriles.

• Bulletin of the Korean Chemical Society
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• 제9권6호
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• pp.352-355
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• 1988

${\alpha},{\beta}$-unsaturated carboxylic acid derivatives such as esters, amides, and nitriles are readily reduced to the corresponding saturated derivatives by potassium triphenylborohydride, $KPh_3BH$, in the presence of phenol, a quenching agent, in excellent yields.

• Archives of Pharmacal Research
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• 제13권3호
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• pp.274-277
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• 1990

It has been found that $\alpha, \beta$-unsaturated nitrile derivatives 1-3 reached with S- methylisothiourea to give the prpone derivatives 4-6 respectively. Cyclisation of 4-6 using ethanolic hydrochloric acid afforded the pyridine derivatives 7-9 in good yields. On the other hand, the reactions of hydrazine hydrate and of phenylhydrazine with each of 7-9 gave the corresponding pyrazolopyridine derivatives 10-15. The structures of the newly synthesised derivatives were assigned on the basis of elemental analyses, IR and $^1H$-NMR spectral data studies.

• Bulletin of the Korean Chemical Society
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• 제12권6호
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• pp.644-649
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• 1991

The approximate rates and stoichiometry of the reaction of excess lithium tris(dibutylamino)aluminum hydride (LT-DBA) with selected organic compounds containing representative functional groups under standardized conditions (tetrahydrofuran, $0^{\circ}C$) were studied in order to characterize the reducing characteristics of the reagent for selective reductions. The reducing ability of LTDBA was also compared with those of the parent lithium aluminum hydride and the alkoxy derivatives. The reagent appears to be much milder than the parent reagent, but stronger than lithium tri-t-butoxyaluminohydride in reducing strength. LTDBA shows a unique reducing characteristics. Thus, the reagent reduces aldehydes, ketones, esters, acid chlorides, epoxides, and amides readily. In addition to that, ${\alpha},{\beta}$-unsaturated aldehyde is reduced to ${\alpha},{\beta}$-unsaturated alcohol. Quinones are reduced to the corresponding diols without evolution of hydrogen. Tertiary amides and aromatic nitriles are converted to aldehydes with a limiting amount of LTDBA. Finally, disulfides and sulfoxides are readily reduced to thiols and sulfides, respectively, without hydrogen evolution.

• Bulletin of the Korean Chemical Society
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• 제8권4호
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• pp.313-318
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• 1987

The approximate rate and stoichiometry of the reaction of excess Thexylbromoborane-methyl sulfide, $ThxBHBr{\cdot}SMe_2,$ with selected organic compounds containing representative functional groups under standardized conditions (methylene chloride, $0^{\circ}C)$ were studied in order to characterize the reducing characteristics of the reagent for selective reductions. The selectivity of the reagent was also compared to the selectivity of thexylchloroborane-methyl sulfide. Thexylbromoborane appears to be a much milder and hence more selective reducing agent than thexylchloroborane. The reagent tolerates many organic functionalities. Thus, the reagent shows very little reactivity or no reactivity toward acid chlorides, esters, epoxides, amides, nitro compounds including simple olefins. However, this reagent can reduce aldehydes, ketones, carboxylic acids, nitriles, and sulfoxides. Especially the reagent reduces carboxylic acids including ${\alpha},{\beta}$ -unsaturated ones and nitriles to the corresponding aldehydes. In addition to that, thexylbromoborane shows good stereoselectivity toward cyclic ketones, much better than the chloro-derivative.

• Bulletin of the Korean Chemical Society
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• 제15권8호
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• pp.644-649
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• 1994

The approximate rates and stoichiometry of reaction of excess dipyrrolinoaluminum hydride (DPAH) with selected organic compounds containing representative functional groups under standardized conditions (tetrahydrofuran, 0, reagent : compound=4 : 1) were examined in order to define the characteristics of the reagent for selective reductions. The reducing ability of DPAH was also compared with that of bis(diethylamino)aluminum hydride (BEAH). The reagent appears to be stronger than BEAH, but weaker than the parent reagent in reducing strength. DPAH shows a unique reducing characteristics. Thus, the reagent reduces aldehydes, ketones, esters, acid chlorides, epoxides, and nitriles readily. In addition to that, ${\alpha},\;{\beta}$-unsaturated aldehyde is reduced to the saturated alcohol. Quinone are reduced cleanly to the corresponding 1,4-reduction products. The examination for possibility of achieving a partial reduction to aldehydes was also performed. Both primary and tertiary aromatic carboxamides are converted to aldehydes with a limiting amount of DPAH. Finally, disulfides and sulfoxides are readily reduced to thiols and sulfides, respectively.

• 대한화학회지
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• 제21권2호
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• pp.108-120
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• 1977

수소화붕소리튬-테트라히드로푸란용액의 환원특성에 대한 계통적인 연구가 52가지의 대표적인 작용기를 가진 유기화합물을 가지고 표준조건($0^{\circ}$, 테트라히드로 푸란)에서 대략의 반응속도 및 정량 관계를 알아봄으로서 이루어 졌다.