• Elastomers and Composites
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• 제51권2호
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• pp.99-105
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• 2016

Alkoxy modified silicone (PAMS) was synthesized from hydroxyl-terminated polydimethylsiloxane (OH-PDMS) and vinyltrimethoxysilane (VTMO) under alkali catalyst (NaOH and KOH) at room temperature ($25^{\circ}C$) via condensation polymerization. Then, the structural verification of the synthesized PAMS was confirmed using $^1H$-NMR and FT-IR spectroscopy. The reaction rate of PAMSs was studied in terms of the concentration variation of alkali catalyst. The reaction rate increased with the concentration of alkali catalyst, but no correlation between conversion and concentration of alkali catalyst was observed.

• Bulletin of the Korean Chemical Society
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• 제14권2호
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• pp.183-187
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• 1993

Aryl carbenic anion radicals have been generated from the corresponding alkoxy-aryl diazo compounds by unimolecular decomposition reaction in various electrolyte/solvent systems. The electrochemical reductions of alkoxy-aryl diazo compounds in the electrolyte/solvent system are shown to initially be a one-electron process which affords the corresponding anion radicals. The unimolecular loss of nitrogen is favored at the propagation step and accelerated by the oxygen and carbon atoms of alkoxy group adjacent to the diazo function. The structure of the carbene anion radical in the termination is considered to be a resonance hybrid.

• Bulletin of the Korean Chemical Society
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• 제19권2호
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• pp.243-249
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• 1998

The reaction of alcohol with a solution of thexylborane (ThxBH2) in tetrahydrofuran (THF) provides a new class of mild and selective reducing agents, thexylalkoxyboranes (ThxBHOR: R=Et, i-Pr, i-Bu, s-Bu, t-Bu, Ph). In order to elucidate the effect of the alkoxy group in reduction reactions, the reducing power of ThxBHOR toward selected organic compounds containing representative functional groups under practical conditions (THF, 25°, the quantitative amount of reagent to compound) has been investigated. Generally, the reactivity of ThxBHOR is largely dependent upon the alkoxy substituent. ThxBHOR can be synthesized from a variety of alcohols, thus allowing control of the steric and electronic environment of these reagents.

• Bulletin of the Korean Chemical Society
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• 제8권4호
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• pp.276-280
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• 1987

Several chiral potassium B-alkyl-9-boratabicyclo[3.3.1]nonanes $(K\; B-R^*-9-BBNH)$ and potassium B-alkoxy-9-boratabicyclo[3.3.1]nonanes $(K \;B-OR^*-9-BBNH)$ were synthesized by treatment of the corresponding trialkylboranes and dialkylmonoalkoxyboranes with a small excess of potassium hydride. The chiral B-alkoxy derivatives generally reduce representative ketones, such as acetophenone and 3-methyl-2-butanone, with greater optical induction than the corresponding B-alkyl derivatives, suggesting the involvement of the oxygen atom in the control process for asymmetric synthesis.

• Journal of Photoscience
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• 제2권2호
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• pp.77-81
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• 1995

Photoreactions of pseudosaccharin ethers have been investigated. Pseudosaccharin 3-allyl ether undergoes a facile photoreaction via reaction pathways involving homolysis of bond between pseudosaccharyl oxygen and 3-allyl carbon, and excited nucleophilic substitution of allyloxy group by solvent which are not quenched by oxygen present in the reaction. Product yield demonstrates that the homolysis pathway predominates over the nucleophilic substitution in ca. 7:1 ratio. In contrast, pseudosaccharin alkyl ethers follow different reaction routes to produce two products, solvent-substituted pseudosaccharin alkyl ethers and reduction products, 3-alkoxy-1, 2-benzisothiazoles. The formations of reduction products, 3-alkoxy-1, 2-benzisothiazoles are completely quenched by oxygen.

• Bulletin of the Korean Chemical Society
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• 제26권11호
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• pp.1869-1871
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• 2005

• 한국재료학회지
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• 제2권6호
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• pp.398-407
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• 1992

Cholesteryl S-alkoxybenzene thiocarbonates를 합성하여 그들의 상전이 온도를 조사하였다. 이 계열 화합물들은 모두 호변성 cholesteric 액정상을 나타낸다. 상전이 온도는 시차주사열분석기 (DSC)로 측정하였으며, 측정된 cholesteric-isotropic 상전이 온도는 alkoxy 사슬 길이 증가에 따라 감소한다.

• 약학회지
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• 제39권1호
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• pp.41-47
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• 1995

An efficient and stereoselective synthetic route to the trisubstituted hydroxy cyclopentane as an useful synthetic intermediate for carbaprostacyclin is described. Pd(0)-mediated intramolecular alkylation of allylic carbonate has been employed as a key reaction.

• Bulletin of the Korean Chemical Society
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• 제17권10호
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• pp.892-899
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• 1996

In order to elucidate the effect of alkoxy substituent in thexylborane and hence establish their usefulness as hydroborating agent, reactions of alkenes and alkynes with thexylalkoxyborane (ThxBHOR; R=Et, i-Pr, i-Bu, sec-Bu, t-Bu, Ph) were investigated in detail. The reagents readily hydroborated alkenes and alkynes of various structural types at 25 ℃ in excellent regioselectivity. The selectivity increases consistently with increasing steric size of alkoxy substituent. Especially, the selectivity achieved by the sec-butoxy derivative is comparable to that previously achieved by thexylhaloborane-methyl sulfide (ThxBHX·SMe2), the most selective hydroborating agent known.

• Bulletin of the Korean Chemical Society
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• 제20권8호
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• pp.929-934
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• 1999

2-( β-Alkoxyvinyl)-4-(1-hydroxyalkyl)pyrroles (14) were synthesized from 4-acylpyrrole-2-carboxylates (8) by sequential reduction of their acyl and alkoxycarbonyl groups to give 4-(1-hydroxyalkyl)pyrrole-2-carbalde-hydes (13) followed by Wittig reaction of the aldehydes with the ylide of alkoxymethylphosphonium chloride. Diels-Alder reaction of 2-(β-alkoxyvinyl)-4-(1-hydroxyalkyl)pyrroles with trans-methyl β-nitroacrylate gave 6-alkoxy-3-(1-hydroxyalkyl)-5-nitro-4,5,6,7-tetrahydroindole-4-carboxylates (3).