• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1209-1212
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• 2012

In spite of many reports in the literature concerning with oxidation of benzylic alcohols to carbonyl compounds with 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) in stoichiometric amounts or even more, we surprisingly found that benzylic alcohols are directly oxidized to oximes using a catalytic amount of DDQ in the presence of hydroxylamine hydrochloride under solvent-free conditions. The present tandem catalytic method can be efficiently used for preparation of oximes in the presence of some other functional groups with excellent chemoselectivity.

• Clean Technology
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• v.22 no.4
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• pp.269-273
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• 2016

The benzylic bromination of methoxyimino-o-tolyl-acetic acid methyl ester (1) into (2-bromomethyl-phenyl)-methoxyimino-acetic acid methyl ester (2) using N-bromosuccinimide in the presence of 2,2'-azobisisobutyronitrile in various reaction solvents were investigated. The efficiency of the reaction was found to be sensitive to the kind of reaction solvents. We found the benzylic bromination of 1 to 2 can be performed in 1,2-dichlorobenzene as reaction solvent superior to the classic Wohl-Ziegler procedure in both reaction time and isolated yield (8 h vs 12 h, 92 vs 79%). This system provides clean, rapid, and high-yielding reactions with replacement of conventional solvents, such as tetrachloromethane, by less-toxic 1,2-dichlorobenzene.

• Bulletin of the Korean Chemical Society
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• v.23 no.11
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• pp.1667-1670
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• 2002

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.3107-3108
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• 2009

• Bulletin of the Korean Chemical Society
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• v.26 no.3
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• pp.454-456
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• 2005

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2405-2406
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• 2012

• Bulletin of the Korean Chemical Society
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• v.25 no.8
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• pp.1143-1146
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• 2004

A simple and effective procedure for conversion of primary, secondary, allylic and benzylic alcohols into the corresponding iodides is described using $CeCl_3{\cdot}7H_2O/NaI\;over\;SiO_2$ under microwave irradiation. Benzylic alcohols are selectively converted in the presence of saturated alcohols into their corresponding benzylic iodides under these conditions.

• Bulletin of the Korean Chemical Society
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• v.12 no.2
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• pp.149-153
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• 1991

Chlorotrimethylsilane reacts with chromic anhydride to form a very reactive neutral chromium (Ⅵ) oxidizing agent. The active oxidizing species is not trimethylsilyl chlorochromate as was previously reported but chromyl chloride generated in equilibrium concentration. This oxidizing agent was proved very suitable for benzylic oxidations of toluenes and alkylbenzenes to benzaldehydes and aralkyl ketones. Dichlorodimethylsilane and trichlormethylsilane also react with chromic anhydride to form chromyl chloride in an equilibrium concentration.

• Bulletin of the Korean Chemical Society
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• v.12 no.2
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• pp.182-188
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• 1991

The reactions of aniline with benzyl and phenacyl compounds are studied by the AM1 method. Two types of modeling were adopted: Cation-neutral, in which a proton is attached to the leaving group F and anion-neutral model, in which aniline was replaced by phenoxide with Cl as the leaving group. The cation-neutral model represented the reactvery well, reproducing the various solution-phase experimental results. In the benzyl system, the ${\pi}$-electrons of the two rings (X-ring in the nucleophile and Y-ring in the substrate) interact conjugatively in the transition state (TS) resulting in a bond contraction of the $C_{\alpha}-C_{Y1}$ bond (benzylic effect), whereas in the phenacyl system the ${\pi}$ electrons of the X-ring delocalizes more efficiently into the carbonyl group than into the Y-ring (resonance shunt effect) with a bond contraction of the $C_{\alpha}-C_{\beta}$ bond. The bond contraction in the benzylic effect was substantially greater than that in the resonance shunt effect. The TS was rather loose for benzyl while it was tighter for phenacyl system. Various bond length changes with substituents in the TS were, however, found to be irregular.

• Bulletin of the Korean Chemical Society
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• v.16 no.4
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• pp.371-374
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• 1995