• Bulletin of the Korean Chemical Society
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• v.8 no.4
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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.

• Bulletin of the Korean Chemical Society
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• v.27 no.7
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• pp.986-990
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• 2006

As key nucleoside intermediates for the preparation of cyclic adenosine diphosphate ribose (cADPR, 1) analogues, 8-alkyl-2' (or 3')-azido(or amino)-adenosine derivatives (16-19) were successfully prepared by alkylating selectively protected adenosine derivatives (12, 13) via Pd(0) catalyzed cross-coupling reaction with tetraalkyltin reagents, followed by the sugar modification of these 8-alkyl-adenosine derivatives according to our precedent procedure. Compared to other precedent procedures, our 8-alkylation methodology using selectively TBDMS-protected 8-alkyl adenosine derivatives as starting materials will be utilized very conveniently to prepare highly functionalized adenosine analogues, which will be serve as key intermediates for the cADPR.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.10
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• pp.1417-1422
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• 2012

Alkyl glucosides were synthesized using the transglycosylation reaction of Celluclast, the cellulase from Trichoderma reesei, with cellobiose and various alcohols. Glucose as a by-product of the reaction was removed using the immobilized yeast system. Among the alkyl glucoside products, the acceptor products of methanol and ethanol were confirmed as methyl ${\beta}$-D-glucopyranoside and ethyl ${\beta}$-D-glucopyranoside via MALDI-TOF MS and enzymatic analysis. Optimal yields of methyl ${\beta}$-glucoside and ethyl ${\beta}$-glucoside were 65.3% (mol/mol) and 59.0% (mol/mol), respectively, based on cellobiose consumed.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1009-1011
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• 2009

Nano-structured conducting polypyrroles were synthesized in the ionic liquids (ILs) based on 1-alkyl-3-methylimidazolium family with tetrachloroferrate as an anion ($C_n\;mim\;[FeCl_4]\;with\;n\;=\;4,\;8,\;and\;12$). The polypyrrole nanostructures synthesized in ILs were formed as spherical shapes. For ionic liquids with alkyl side chain length $C_4,\;C_4\;mim\;[FeCl_4]$, the size of particles was ranged around 60-nm with a relatively narrow size distribution. As the length of alkyl chain increases, the particle sizes become larger and their distributions become wider. The self-assembled local structures in the solvent ionic liquids are likely to serve as templates of highly organized nano-structured polymers. The length of the alkyl chain in ionic liquids seems to affect these local structures.

• Bulletin of the Korean Chemical Society
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• v.25 no.10
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• pp.1531-1537
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• 2004

Twenty four thiol-functionalized ionic liquids based on imidazolium cation, 1-(12-mercaptododecyl)-3-alkylimidazolium salts, have been synthesized, and utilized to investigate the effects of alkyl-chain length and anion on the wettability of Au surfaces on the basis of self-assembled monolayers presenting [(CnSAMIM)X], where n = 1-6, X = Br, $BF_4$, $PF_4$ and $NTf_2$. Water wettabilities of the surfaces were measured as a water contact angle by contact angle goniometry. It was found that water wettability of the Au surfaces coated with imidazolium ions was largely dependent not only on counter anions but also on the length of alkyl chains. In the case of SAMs of N-alkylimidazolium ions having short length of N-alkyl chain (C1-$C_4$), anions played great role in determining water wettability of the surfaces.

• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1771-1775
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• 2005

An efficient and environment friendly method has been described for the synthesis of various 2-alkyl-4-hydroxy-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxides starting from N-alkylation of sodium obenzosulfimide in an ionic liquid for the first time. Ring cleavage and ring closure of the resulting product were achieved in a single step in a cost effective solvent (methanol) followed by N-alkylation of resulting alkyl 4-hydroxy-2H-1,2-benzothiazine-3-carboxylate in ionic liquid while boron triflouride was used as a catalyst along with molecular sieves in carboxamide formation step.

• Journal of Ceramic Processing Research
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• v.19 no.5
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• pp.361-368
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• 2018

We investigated the interfacial properties of fluorocarbon self-assembled monolayers (FC-SAMs) with different alkyl chain lengths. It was found that the substrate characteristics were changed rapidly with the fabrication time and temperature of the SAM. FC-3SAM, which has the shortest alkyl chain in this study, showed a contact angle of $54.1^{\circ}$ when it was fabricated in an electric oven at $60^{\circ}C$ for the first minute. The FC-3SAM showed a contact angle of up to $76.9^{\circ}$ when it was fabricated in an electric oven at the same temperature condition for 180 minutes. FC-10SAM, which has the longest alkyl chain in this study, showed a contact angle of $64.7^{\circ}$ when it was fabricated at a temperature condition of $60^{\circ}C$ for 1 minute, and a contact angle of $98.7^{\circ}C$ at a temperature condition of $60^{\circ}C$ for 180 minutes. It was found that the FC-10SAM shows an increased contact angle and hydrophobic properties due to a well-aligned molecular structure resulting from a strong van der Waals force. In contrast, the FC-3SAM shows a small contact angle due to the intermolecular disorder resulting from a weak van der Waals force. The average roughness of FC-SAMs was investigated using AFM. The surface roughness of FC-SAMs, which verifies the results of contact angle, was confirmed. At a fabrication time of 120 minutes, the FC-10SAM showed an improvement in average roughness by 62% compared to that of FC-3SAM due to its good alignment.

• Archives of Pharmacal Research
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• v.15 no.1
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• pp.5-8
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• 1992

5-Alkyl-3-(1-thioxolanyl-cyclohexenyl)-resorcinol derivatives are readily prepared by boron trifluoride-on-alumina-catalyzed formation of 5-alkylresorcinols with 1-thioxolanyl-2-cyclohexenol; their formation depends on the nature of the alkylgroup. The yield is the highest with 5-(1, 1-dimethylheptyl)-resorcinol. The one with 5-pentylresorcinol is higher than 5-methylresorcinol and resorcinol apparently because of steric effects. The yields of the products increases: 3a (10%), 3b (20%) 3c (48%) and 3d (77%).

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.653-658
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• 2010

• Bulletin of the Korean Chemical Society
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• v.17 no.4
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• pp.362-365
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• 1996

Carbonyl compounds 1, alkyl- and arylaldehydes and alkyl, aryl, benzylic, and cyclic ketones were converted to the corresponding 1,3-dioxolanes 2 and 1,3-dioxanes 4 with ethylene glycol and 2,2-dimethyl-1,3-propanediol in the presence of 1-3 mol% of 1-(p-substituted)benzyl-1,1-dimethyl-2-(p-substituted)-benzoyl hydrazinium hexafluoroantimonates 3 in high yields.