• Bulletin of the Korean Chemical Society
• /
• 제33권1호
• /
• pp.55-59
• /
• 2012

Treatments of organic isothiocyanates (R-NCS) with $NaN_3$ in the presence of pyridine in water at room temperature gave corresponding various organic tetrazole-thiones, [$S=CN_4(R)$] (R = alkyl or aryl). Isolated products are obtained as white or yellow solids in good yields (76-97%). The molecular structure by X-ray diffraction study for one of products shows the proposed formation. In addition, one-pot synthesis of 1-substituted 5-alkyl(or aryl)sulfanyltetrazoles has been demonstrated. Addition of alkyl or aryl halides into the mixture of organic isothiocyanates, $NaN_3$, and pyridine in water at room temperature exclusively formed 1-substituted 5-alkyl(or aryl)sulfanyltetrazoles (S-derivatives) in high yields.

• 대한화학회지
• /
• 제53권2호
• /
• pp.224-228
• /
• 2009

• Archives of Pharmacal Research
• /
• 제20권5호
• /
• pp.507-509
• /
• 1997

Several new spiro compounds were synthesized via one-pot ternary condensation of isatin, malononitrile and each of thiobarbituric acid, barbituric, 3-methyl-pyrazolin-5-one, 1-phenyl-3-methyl-pyrazolin-5-one, acetylacetone, benzoylacetone, ethyl acetoacetate, phenacyl cyanide or ethyl-cyanoacetate dimer. Structures and reaction mechanisms were reported and supported via a second synthetic route.

• Bulletin of the Korean Chemical Society
• /
• 제33권5호
• /
• pp.1556-1560
• /
• 2012

A simple highly versatile and efficient method has been developed for the three-component coupling of aldehydes, amines and alkynes to prepare propargylamines, in the presence of a catalytic amount of $BiCl_3$. The advantages of methods are high yield, mild reaction conditions, no environmental pollution and easy work up procedure.

• Bulletin of the Korean Chemical Society
• /
• 제33권2호
• /
• pp.383-386
• /
• 2012

A convenient synthesis of sulfonamides from thiols and disulfides is described. In situ preparation of sulfonyl chlorides from thiols is accomplished by oxidation with 1,3-dichloro-5,5-dimethylhydantoin (DCH) under Nbenzyl-trimethylammonium chloride and water. The sulfonyl chlorides are then further allowed to react with excess amine in the same reaction vessel.

• Bulletin of the Korean Chemical Society
• /
• 제33권8호
• /
• pp.2581-2584
• /
• 2012

Hexafluoroisopropanol (HFIP) is explored as an effective medium for the synthesis of quinoxaline derivatives in high yields at room temperature. The solvent (HFIP) can be readily separated from reaction products and recovered in excellent purity for direct reuse.

• Archives of Pharmacal Research
• /
• 제17권1호
• /
• pp.39-41
• /
• 1994

Various N,N'-disubstituted ureas 5 were easily prepared from the corresponding primary amide 1 by tratment with N-Bromophthalimide $(NBP)-AgOAc-RNH$_{2}$ 4 in dry N,N-dimrthylformamide (DMF). This reaction envolved the intemediate formation of isocyanate 3 from amide 1 via Hofmann rearrangement by treatment with AgOAc and NBP and nucleophilic addition of amine 4 to this isocyante 3. This method is simple enough to be applied to the synthesis of various N,N'-disubstututed ureas scale conviently.

• Archives of Pharmacal Research
• /
• 제27권12호
• /
• pp.1189-1193
• /
• 2004

The total synthesis of norneolignans isolated from Krameria species, 2-aryl-5-(E)-propenylbenzofurans (5, 11), is described. The key step involves the one-pot reaction for 2-arylbenzofurans (2, 7) from 4-hydroxyphenylacetone with 4'-acetoxy-2-chloro-2-(methylthio)acetophenone (1) and 2-chloro-2-methylthio-(2',4',6'-trimethoxy)acetophenone (6) under Friedel-Crafts reactionconditions.

• Bulletin of the Korean Chemical Society
• /
• 제33권11호
• /
• pp.3559-3564
• /
• 2012

An efficient one-pot synthesis of ${\beta}$-acetamido ketones was accomplished by AgOTf-catalyzed multicomponent reactions of substituted acetophenones with aromatic aldehydes and acid chloride in acetonitrile in high yields. The methods offer several significant advantages of easy handling, mild reaction conditions, and use of effective and non-toxic catalyst.

• Bulletin of the Korean Chemical Society
• /
• 제30권3호
• /
• pp.695-699
• /
• 2009

A short and efficient synthesis of (2S,3S)-safingol from commercially available D-ribo-(2S,3S,4R)-phytosphingosine is described. The highlights of the synthesis are a stereoselective one-pot transformation of a diol into an epoxide under phase transfer catalytic conditions and a regioselective epoxide-opening reduction with a hydride reagent.