• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
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• pp.1-2
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• 2003

Some new synthetic routes for the preparation of poly (isobutyl vinyl ether) (P(IBVE)) having a controllable molar mass with narrow distribution via catalytic or photoinduced living cationic polymerization and their conversion to corresponding PVA have been developed. It was found that the combination of iodomethyl methyl ether (IMME)-zinc iodide is effective in the initiation of the catalytic and the various combinations of diphenyliodonium halides, well known photocationic initiators (DPIX) with zinc halides (ZnX$_2$) are also useful in photoinduced living cationic polymerization of isobutyl vinyl ether (IBVE). Polymerization both in the catalytic and photoinduced systems precede until the full consumption of the monomer and the rate of polymerization increases as the concentration of the catalyst or photoinitiator. The number average molar mass of the resulting polymer is proportional with % conversion, which is determined by the ratio of monomer consumed and the initial values of the catalyst or initiator. The living nature was also confirmed by subsequent monomer addition technique.

• 한국결정성장학회지
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• 제11권3호
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• pp.102-105
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• 2001

A parametric cmpariosn of etch rate and etch selectivity has been performed for GaN, InN and AIN etched in chlorine- and boron halides-based Inductively Coupled Plasma (ICP) discharges. Chlorine-based chemistries produced controllable etch rates (50~150 nm/min) and maximum etch selectivities ~6 for InN over GaN and ~10 for InN over AlN. Maximum etch selectivities of ~100 for InN over GaN and InN over AlN were obtained in boron halides-based discharges and smooth etched surface morphologies were also achieved.

• Archives of Pharmacal Research
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• 제13권1호
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• pp.9-13
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• 1990

4, 5-Diphenyl-2-mercaptiomidazole (I) was reacted with hydraziodyl halides IIa-d togive the S-alkyl derivatives III-a-d. Cyclization of IIIa-d afforded imidazo[2, 1-b]-thiazole derivatives Vla, b and VII. Treatment of 1 with a-chloroethylacetoaccetate (IV) gave ethyl 2(4, 5-diphenyl-2-imidazolinylthio)-3-keto-butyrate (V). Compound V coupled with benzendiazonium chloride to give the corresponding phenylhydrazo compound IIId. On heating V with polyphosphoric acid, cyclization took place and 2-acetyl-5, 6-diphenyl-imidazo [2, 1-b] thiazol-3-one (VIII) was obtained. The compound VIII was condensed with aromatic aldehydes to yield the cinnamoyl derivatives 1Xa, b. The antimicrobial activities of compounds IIIa-d, V, VIa, VII were examined.

• Archives of Pharmacal Research
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• 제15권1호
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• pp.14-19
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• 1992

Diazotized primary artomatic amines 4 coupled with the ketosulfones 1-3 in ethanol in the presence of sodium acetate at $0^\circ{C}$ to afford the corresponding bydrazones 5-7. Also diazotized 3-aminopyrazoles 14 coupled with 1-3 in ethanolic sodium acetate to give the pyrazolotriazines 18-20 in good yields. Compounds 5-7 and 18 can also be obtained from the reaction of hydraziodoyl halides 8-10 and 21 with sodium benzenesultinate. The hydrazones 11-13 can easy be oxidized to the hydrazones 5-7, using hydrogen peroxide in acetic acid.

• Nuclear Engineering and Technology
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• 제5권1호
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• pp.20-25
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• 1973

Phenacyl halides의 할로겐 교환반응을 무수 아세톤 중에서 방사성 할라이드 이온을 사용하여 속도론적으로 연구하였다. 반응은 SN2반응이며 할라이드 이온의 상대적 친핵성의 순서는 Phenacyl chloride에 있어서는 Cl->I->Br-이고 Phenacyl bromide에 있어서는 I>Cl->Br-였다. 이것을 할라이드 이온의 용매화 효과와 그리고 HSAB 원리로 설명하였다.

• 대한화학회지
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• 제11권4호
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• pp.121-125
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• 1967

各種 아민과 할로겐化合物間의 Charge Transfer Complex 形成與否를 檢討하여 보았다. Pyridine Tridthylamine, Piperidine Ethanolamine Triethanolamine, Aniline, Diethylamine 等의 아민類와 四鹽化炭素 또는 클로로폼의 混合溶液을 n-Hexane 溶媒存在下에서 紫外線吸收 스펙트라를 檢査한 結果 장파장쪽의 Shift가 있었으며 特히 Diethylamine과 Triethylamine은 클로로폼 또는 四鹽化炭素와 1:1 Charge Transfer Complex를 形成하였고, Piperidine은 接觸的 Complex를 形成하는 것이 確認되었다. Complex의 形成경향과 아민의 Nucleophilicity와의 關係를 論議하였다.

• 대한화학회지
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• 제14권3호
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• pp.221-228
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• 1970

The tendency of forming a charge transfer complex between furfuryl derivatives (2-methyl furan, furfuryl acetate, and Ethyl 2-furoate) and halides(Iodine, Iodine monochloride, and Trichloro bromo methane) was studied by means of ultra violet spectrophotometry. In case of furfuryl acetate the formation of the complex could not be distinctly detected by this method. Iodine and trichloro bromo methane could show a distinct formation of charge transfer complex in the U.V. region, whereas iodine monochloride shows a possibility of forming an addition compound rather than the charge transfer complex itself. The results were discussed in conjunction with the stability of the furfuryl ring.

• Bulletin of the Korean Chemical Society
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• 제33권4호
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• pp.1231-1234
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• 2012

A one-pot efficient procedure for the synthesis of 2,4,5-triaryl-1H-imidazole derivatives in good to excellent yields by reaction between hexamethyldisilazane and arylaldehydes, benzyl alcohols, benzyl halides in the presence of molecular iodine has been developed. The remarkable advantages of this method are the simple workup procedure, high yields of products, and the availability of reagents.

• 대한화학회지
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• 제18권1호
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• pp.3-7
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• 1974

확장 Huckel법을 사용하여 술페닐, 술피닐 및 술포닐기가 할라이드의 $S-N2$형 반응에 미치는 효과를 고찰하고 각종 반응성 지수를 비교, 검토한 결과 bond formation과정의 반응성 지수중 Frontier electron에 의한 것이 가장 합리적인 것임을 밝혔다.

• Macromolecular Research
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• 제14권3호
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• pp.338-342
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• 2006

The kinetic features of polymerization with an active site comprising cobalt dihalides ($CoX_2$, where X=Cl, Br, I) activated by methylaluminoxane (MAO) were investigated in 1,3-butadiene polymerization. The catalytic system exhibited the characteristic features of living polymerization. The initiation ($k_i$) and propagation ($k_p$) rate coefficients were estimated using the kinetic model for slow initiation previously reported by Shiono et al. The energy of activation fur the propagation reaction was calculated to be 27-30 $kJmol^{-1}$. The marked changes in reaction rate observed with different halides could be adequately described in terms of variations in the initiation process, with the same Arrhenius curve fitting propagation rate coeffcients estimated from all three halides, suggesting that the halide does not participate in the growing chain end.