• Bulletin of the Korean Chemical Society
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• 제27권10호
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• pp.1674-1676
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• 2006

• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3535-3536
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• 2012

• Bulletin of the Korean Chemical Society
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• 제30권2호
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• pp.327-333
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• 2009

For the Pt-catalyzed nucleophilic addition of enones, Pt complexes were employed in the presence of various phosphine ligands and $H_2\;(or\;Et_3SiH),$ affording inter- and intra-molecular coupling products in good to modest yield. Depending on reaction protocols, different phosphine ligands were required to optimize the conditions. In the aldol reaction, the Pt catalyst involving $P(2,4,6-(OMe)_3C_6H_2)3\;or\;P(p-OMeC_6H_4)_3$ was chosen. Michael reaction proceeds in good yields in the presence of $P(p-CF_3C_6H_4)_3$. Regarding the activity of the reductants, $H_2$ exhibited superior activity to $Et_3SiH$, resulting in a shorter reaction time and higher yield in the aldol and Michael reaction. In light of the deuterium labeling studies, the catalytic cycle including the hydrometalation of the enones by the platinum hydride species was proposed.

• Bulletin of the Korean Chemical Society
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• 제29권1호
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• pp.76-80
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• 2008

Reductive acetylation of a variety of carbonyl compounds such as aldehydes, ketones and a,b-unsaturated enals/enones was carried out efficiently with pyridine zinc borohydride, (Py)Zn(BH4)2, in a mixture of THF-EtOAc at room temperature or under reflux condition. The corresponding acetates were obtained in high to excellent yields. In addition, chemoselective reductive acetylation of aldehydes over ketones was achieved perfectly with the reagent at room temperature.

• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.620-624
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• 2012

An efficient synthesis of poly-substituted furans, pyrroles, and thiophenes was carried out in a regiocontrolled manner via a three-step process; (i) conjugate addition of methyl cyanoacetate derivatives to ${\alpha}$,${\beta}$-enones, (ii) CuI-mediated aerobic oxidation, and (iii) Paal-Knorr type synthesis of five-membered heterocycles.

• Bulletin of the Korean Chemical Society
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• 제34권3호
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• pp.936-942
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• 2013

Series of (E)-1-aryl-3-(2-pyrrolyl)-2-propenones, that were aldol condensation products between pyrrole-2-carbaldehyde and m- and p-substituted acetophenones, were prepared and their $^1H$ and $^{13}C$ NMR spectra were examined to obtain the information on the conformation of the enone system. Similar studies were carried out with (E)-3-aryl-1-(2-pyrrolyl)-2-propenones that were prepared from 2-acetylpyrrole and m- and p-substituted benzaldehydes. The substituent chemical shifts were studied by applying the Hammett relationship.

• 통합자연과학논문집
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• 제2권3호
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• pp.185-189
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• 2009

The new MPV-type reagent, Al-fluorodiisobutylalane (DIBAF), has been prepared and their reducing characteristics in the reduction of selected organic compounds containing representative functional groups have been examined in order to find out a new reducing system with unique applicability in organic synthesis. In general, the reagent is extremely mild, showing only reactivity toward aldehydes, ketones, and epoxides. The reagent achives a clean 1,2-reduction of enals to the corresponding allylic alcohols in a 100% purity, but shows no reactivity toward enones. The reagent also shows an excellent regioselective cleavage of substituted epoxides. In addition, DIBAF produces the thermodynamically more stable alcohol epimer in high stereoselectivity in the reduction of cyclic ketones.

• Bulletin of the Korean Chemical Society
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• 제31권6호
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• pp.1689-1694
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• 2010

Substituent chemical shifts were examined for the 2- and 3-thiophene derivatives of chalcone and compared to the thiophene series of derivatives with the phenyl series. The chemical shift values for the ${\alpha}$-carbons of the enones showed and inverse correlation with the Hammett $\sigma$ values, but the correlation coefficients were moderate (r = 0.836 - 0.878). On the other hand, the $\beta$-carbons showed a normal correlation with excellent correlation coefficients (r = 0.994). The absolute magnitude of the $\rho$ values for the $\alpha$-carbon are about half of those of the $\beta$-carbon. The observation may be the result of a through-space transition of the electronic effect of the substituents in addition to the through bond transition.

• Bulletin of the Korean Chemical Society
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• 제31권10호
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• pp.2961-2966
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• 2010

Reduction of carbonyl compounds such as aldehydes, ketones, $\alpha,\beta$-unsaturated enals and enones, $\alpha$-diketones and acyloins was carried out readily with $NaBH_3CN$ in the presence of wet $SiO_2$ as a neutral media. The reactions were performed at solvent-free conditions in oil bath (70 - $80^{\circ}C$) or under microwave irradiation (240 W) to give the product alcohols in high to excellent yields. Regioselective 1,2-reduction of conjugated carbonyl compounds took place in a perfect selectivity without any side product formation.

• Bulletin of the Korean Chemical Society
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• 제30권7호
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• pp.1445-1451
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• 2009

New benzotriazoles (5-8) or dibenzodiazepine derivatives (11-18) were synthesized starting from 3-[(2-amino- 4,5-disubstitutedphenyl)amino]-5,5-disubstitutedcyclohex-2-enones (1-4) through internal coupling of their diazonium salts or internal Mannich reaction in the presence of aromatic aldehydes. Pharmacological evaluation of benzotriazole and dibenzodiazepine derivatives for their clozapine-like properties revealed that dibenzodiazepine 11 bearing 4-bromophenyl group exhibited the same antipsychotic activity as the reference drug clozapine while the activity of benzotriazole 7 was 25% lesser than that of clozapine. Moreover, compounds 7 and 11 did not show significant CNS depressant activity as well as no or slight neurotoxicity on contrast to clozapine when tested in mice using forced swim, rotarod and horizontal screen tests.