• Archives of Pharmacal Research
• /
• v.27 no.12
• /
• 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
• /
• v.33 no.11
• /
• 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
• /
• v.33 no.12
• /
• pp.4150-4154
• /
• 2012

Efficient synthesis of ${\alpha}$-chloroenones bearing ${\beta}$-carbonates or ${\beta}$-carbamates was achieved by rhodium(II)-catalyzed reaction of cyclic diazodicarbonyl compounds with a variety of chloroformates or carbamyl chlorides in good yields. These reactions provided a useful and rapid route to ${\beta}$-substituted ${\alpha}$-haloenones.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.11
• /
• pp.2697-2700
• /
• 2009

A $Pd(OAc)_2/(o-MeOPh)_3P$ system has been developed for the catalytic Suzuki coupling of aryl bromides with arylboronic acids. Our catalyst system covers a broad spectrum of commonly available arylboronic acids and aryl bromides to provide biaryls in very good yields. The catalyst system works very well in the synthesis of sterically hindered biaryls.

• Bulletin of the Korean Chemical Society
• /
• v.28 no.11
• /
• pp.2061-2064
• /
• 2007

The first efficient synthesis of biologically interesting nigrolineabenzopyran A, blandachromene II, and daurichromene D with the benzopyran moiety has been accomplished using ethylenediamine diacetatecatalyzed reaction as a key step. The key step in these synthetic strategies involves the formation of benzopyran moiety via an electrocyclization reaction.

• Bulletin of the Korean Chemical Society
• /
• v.17 no.11
• /
• pp.1009-1018
• /
• 1996

A study on the application of vinyl radical cyclization via free radical allylation reaction in the synthesis of various carbocyclic compounds is described. In connection with this study, a new allyl transfer reagent, 2-bromo-3-(phenylthio)propene 1 is developed and it was shown that vinyl radical cyclization through free radical allylation reaction using reagent 1 provides a valuable approach to carbocyclic systems with a reactive exo-alkylidene moiety, which is advantageous for further transformations.

• Bulletin of the Korean Chemical Society
• /
• v.20 no.5
• /
• pp.551-555
• /
• 1999

11-Deoxydaunomycinone 15 and 10-fluoroanthracyclinone derivatives 9, 10 were obtained. Naphthalenone 4 prepared from 2-(2,4-pentadienyl)-1,3-dioxane 2 with methyl vinyl ketone and hydrolysis with HClO4 was condensed with phthalidesulfone 5 through Michael type reaction, and was converted to 7 by epoxidation. Epoxide 7 was transformed to trione 12 using reduction-oxidation or hydrofluorination process, and then to 15 by introducing several functional groups. Compound 8 obtained in the course of the reaction of epoxide 7 and HF/ Pyr was used for the synthesis of compounds 9, 10.

• YAKHAK HOEJI
• /
• v.41 no.4
• /
• pp.480-483
• /
• 1997

The efficient synthesis of p-(acetylamino)phenylacetic acid(7), a antirheumatic agent, is reported. Methyl phenylacetate(3) was prepared from Friedel- Crafts reaction of benzene with methyl ${\alpha}$-chloro-${\alpha}$-(methylthio)acetate(1) followed by reductive desulfurization with zinc dust in acetic acid. Compound(7) was obtained from 3 by a sequence of nitration, reduction, N-acylation, and hydrolysis.

• Archives of Pharmacal Research
• /
• v.13 no.4
• /
• pp.347-350
• /
• 1990

The hydrazine derivative 2 has been utilized for the synthesis of three different fused 1, 2, 4-triazolo [4, 3-a] pyrimidine derivatives 4, 5, &6 and a tetrazolo [1, 5-a] pyrimidine derivative 7. Reaction of 2 with the chalcone analogue 2-thenylidene-2'-acetothienone, gave the pyrazoline derivative 8.

• Journal of Environmental Science International
• /
• v.17 no.3
• /
• pp.351-357
• /
• 2008

In order to develope an efficient way for the synthesis of highly pure 1,4-sorbitan solution from sorbitol, some experimental studies were performed. The reaction showed first order reaction with activation energy of 118.3 KJ/mol. Color of the product solutions changed to brown with reaction temperature and reaction time. The equilibrium contents of 1,4-sorbitan increased with decrease in reaction pressure, but the content of major impurity, sorbide, showed maximum about 550 torr vacuum with $H_3PO_4$ catalyst. The reasonable catalyst configuration was 0.26 wt% PTSA and 1 wt% $H_3PO_2$ and optimum reaction temperature and pressure range was $110\sim120^{\circ}C$ and $700\sim720$ torr vacuum, respectively. At optimum reaction conditions, we could obtain white product solutions of highly pure 1,4-sorbitan with sorbide less than 10 wt%. This white product solution is advantageous for preparation of high quality span, anti-fogging agent.