• Journal of the Korean Chemical Society
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• v.10 no.1
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• pp.43-45
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• 1966

The rate of exchange of I atom between alkyl iodides(ethyl or methyl iodide) and $I_2$ in n-hexane have been determined using $II^{131}$. It is found that the escape of $CH_3$ radicals from a solvent cage is faster than $C_2H_5$ radicals and that photolysis of $C_2H_5I$ is almost identical to that in the case of $CH_3I$.

• Applied Chemistry for Engineering
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• v.7 no.1
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• pp.118-128
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• 1996

N-methyl, N-butyl and N,N-dibutyl chitosan derivatives were prepared by Schiff's base formation and hydrogenation in aqueous media. Furthermore quaternization of the chitosan derivatives was performed in N-methyl-2-pyrrolidone using methyl iodide to obtain water soluble cationic polyelectrolytes. It was confirmed that O-alkylation was occured as well as selective N-alkylation in these reactions. Chitosan and chitosan derivatives with quaternary ammonium iodide showed high flocculation power as the cationic flocculant. When tested on paper mill waste water, they showed high flocculation power, independing of pH range. The flocculation power was increased as the N-alkyl chain length was increased. Among them, N-butyl dimethyl chitosan ammonium iodide showed better flocculation power than chitosan. But, N,N-dibutyl-N-methyl chitosan ammonium iodide showed less flocculation powre than chitosan itself.

• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.1020-1026
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• 1996

Chitosan is the deacetylation product of chitin. Chitosan was converted to N-alkyl chitosan derivatives using proper aldehyde having different alkyl chains, then chitosan derivatives with quaternary ammonium salt were producted by quaternization with methyl iodide. Their antibacterial activities aganst S. aureus(ATCC 6538P) and E. coli (ATCC 14339), gram-positive bacteria and gram-negative bacteria, respectively, as introduced alkyl length were evaluated by shake flask method using colony count. The antibacteiral activity was found to be increased as alkyl chains. hydrophobic goups. These antibacterial agents were more active against S. aureus than E. coli. It may be due to the different of structure of cytoplasmic membrane.

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.1085-1087
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• 2004

• Archives of Pharmacal Research
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• v.17 no.4
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• pp.281-283
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• 1994

5-sec-butylthiomethyl-5-alkyl (methyl or phenyl) hydantoins (3-x) were prepared by the reaction of sec-buylthiomethyl alkyl (methyl or phenyl) ketone (1-2), potassium cyanide and ammonium carbonate. 3-(2-Bromoethyl) hydantoins (5-6) were the reaction products of 5-sec-buythiomethyl-5-alkyl (methyl or phenyl) hydantoin and 1, 2-dibromothane in the presence of potassium hydroxide. Alkylation of 5 and 6 with an excess of alkyl (methyl or ethyl iodide in THF with sodium hydride as base gave three 1-alkyl (methyl or ethyl)-3-(2-bromoethyl) hydantoins (7-9). Treatment of the 2-bromothyl group with potassium thioacelate and triethylamine gave three 1-alkyl (methyl or ethyl)-3-92-acetylthioethyl) hydantoins (10-12). Hydrolysis of the 2-acetylthiuoethyl group with sodium hydroxide in methanol afforded the three 1-alkyl (methyl or ethyl)-3-(2-mercaptorthyl) hydantoins.

• YAKHAK HOEJI
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• v.52 no.6
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• pp.514-519
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• 2008

We developed a convenient synthetic route to 3-alkylated 2-phenyl-4-quinolone derivatives (4a-h and 5a-c), which were expected to retain antitumor activity. A series of 2,3-dihydro-2-hydroxy-2-phenyl-4-quinolones (3a-h) was synthesized through dehydration, dealcoholation and hydration using acid-catalyzed one-pot reaction from anilines and ethyl benzoylacetates. 3-Methyl (or 3,3-dimethyl)-2-phenyl-4-quinolone derivatives 4 and 5 were synthesized from 3a-h through the methylation using methyl iodide. Formation of quinolone nucleus was undertaken with p-toluenesulfonic acid (p-TSA) at $90{\sim}110^{\circ}C$ in toluene for 3${\sim}$7.5 hr over the Dean-Stark apparatus. The key intermediates in these preparations are ${\beta}$-ketoesters 2a-h, which can be readily obtained from the corresponding anilines 1a-e by reaction with ethyl bezoylacetates.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.325-327
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• 2013

• Bulletin of the Korean Chemical Society
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• v.16 no.2
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• pp.153-157
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• 1995

Calix[6]arenes are selectively dialkylated at the lower rim and further functionalized by the aminomethylation and Claisen Rearrangement reactions. Dialkylation was conducted by the reaction of calix[6]arene and alkyl halides such as benzyl bromide, allyl bromide, ethyl bromoacetate, propyl bromide, and methyl iodide under the carefully controlled reaction conditions. Aminomethylation was carried out with the treatment of disubstituted calix[6]arene and secondary amine in the presence of formaldehyde. Claisen rearrangement reaction of the O-diallylcalix[6]arene produced the p-diallylcalix[6]arene.

• Membrane Journal
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• v.5 no.1
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• pp.26-34
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• 1995

In this study, polysulfone was carboxylated(CPSf), as a method of introducing carboxyl group to polymer main chain using direct lithiation reaction. Then, poly(1-alkyl-4-vinylpyridinium iodide-co-divinylbenzene) (MeVpI-DVB) containing pyridinium cation which has an anion selectivity as a fixed carrier was synthesized. And polymer membranes were prepared by mixing CPSf and MeVpI-DVB. Characteristics and permeation of membranes were investigated. As a result of synthesizing CPSf/MeVpI-DVB, blend was formed, not new copolymer. As the content of CPSf amount increasing, thermal stability of membranes was increasing. Ion exchange capacity was 1.0~1.8(meq/g dry mem.) and water content was 0.16~0.26(g $H_2{O}$)/g dry mem.) and fixed ion concentration was 6.4~7.3(meq/g $H_2{O}$) in synthetic membranes. The $Cl^-$ flux showed an increase due to the increase of CPSf content.

• Bulletin of the Korean Chemical Society
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• v.32 no.6
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• pp.2058-2062
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• 2011

The effect of the addition of ionic liquids with four different cations (imidazolium, pyrrolidinium, piperidinium and pyridinium) on the performance of dye-sensitized $TiO_2$ solar cells based on electrolytes containing a t-butylpyridine (TBP) in 3-methoxypropionitrile (MPN) was studied. A total of 18 ionic liquids with mono-, di- and tri-alkyl derivatives were used in the present study, and among them a pyridinium cation with a mono-alkyl group showed better cell efficiency than the others. The best photoelectric conversion efficiency, 7.213%, was obtained using 1-hexylpyridinium iodide with an open-circuit photovoltage ($V_{oc}$) = 0.731 V, a short-circuit photocurrent density ($J_{sc}$) = 16.175 $mA/cm^2$, and a fill factor (ff) = 0.610 under AM1.5 and 100 $mW/cm^2$ illumination.