• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1403-1406
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• 2001

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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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.

• Journal of the Korean Chemical Society
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• v.36 no.4
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• pp.603-605
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• 1992

N-Substituted pyrroles were synthesized from 1,4-dichloro-1,4-dimethoxybutane and primary amines or amide in the presence of Amberlyst A-21 resin. Further reation of these N-substituted pyrroles with 1,4-dichloro-1,4-dimethoxybutane gave N-substituted carbazoles in moderate yields.

• Bulletin of the Korean Chemical Society
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• v.19 no.4
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• pp.488-491
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• 1998

• Bulletin of the Korean Chemical Society
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• v.29 no.11
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• pp.2215-2220
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• 2008

• Bulletin of the Korean Chemical Society
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• v.26 no.8
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• pp.1190-1196
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• 2005

Halopyrroles, N-substituted 2-halopyrroles were prepared by halogenation of N-substituted pyrroles with NBS, NCS, or surfuryl chloride. N-Substituted 3-halopyrroles were synthesized by acid-catalyzed thermal and photochemical isomerization reactions of N-substituted 2-halopyrroles. Both the thermal and photochemical reactions were acid-catalyzed. For the acid-catalyzed isomerization, a mechanism of [1,3] bromine shift followed by deprotonation is operated. For the acid-catalyzed photoisomerization, an excited triplet state of 2-protonated N-benzyl-2-halopyrrole produces an intermediate N-substituted pyrrole complex with halonium ion which is equilibrated with N-substituted pyrrole plus halonium ion, and then the halonium ion newly adds to 3-position of N-substituted pyrrole followed by deprotonation to afford N-benzyl-3-halopyrrole.

• Bulletin of the Korean Chemical Society
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• v.21 no.9
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• pp.909-912
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• 2000

Thallium(I) selective electrodes based on meso-alkyl substituted calix[4]pyrroles such as, meso-octamethyl-calix[4]pyrrole (L1), meso-octaethylcalix[4]pyrrole (L2) and meso-tetraspirocyclohexylcalix[4]pyrrole (L3) as sensor molecules have been pre pared and tested. The conditioned electrode (E4) incorporating L3gave best results with a wide working concentration range of 10-5.5 ~10-1 M near-Nernstian slope of 56.0 mV/decade of activity and detection limit of 10-6.0 M. This electrode exhibited a fast response time of 30 s and high selectivity over Na+ , K+ and other metal ions with only Ag+ interfering. The electrode works well in the pH range 2.0-11.0 and can be successfully employed for the determination of Tl+.This proposed electrode was also used as an indicator electrode in potentiometric titration of Tl+.

• Journal of the Korean Magnetic Resonance Society
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• v.26 no.4
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• pp.40-45
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• 2022

A small cage-like molecule (2) composed of three aminomethyl pyrroles and two hexa-substituted benzenes has been prepared by reduction of its iminopyrrole analogue (1) using NaBH₄. It was revealed by ¹H NMR spectroscopic analyses that cage molecule 2 strongly binds the fluoride anion in polar DMSO-d₆ relative to CDCl₃. Compared to that of compound 1, the lowered affinity of 2 for the fluoride anion is attributable to its increased electron density resulting from the production of thesecondary amine groups.

• Journal of the Korean Chemical Society
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• v.21 no.1
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• pp.32-37
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• 1977

Conformations of nine 2-substituted furan, thiophene and pyrrole compounds have been studied by EHT methods. The preferred conformations of furan derivatives were trans form, which were mainly stabilized by electrostatic interactions. For thiophenes, electronic conjugation between the ring S and carbonyl oxygen was dominant, while for pyrroles both the electrostatic and conjugation effects were operative in determining the preferred conformations. Results of EHT calculation agreed well with experimentally determined preferences.

• Bulletin of the Korean Chemical Society
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• v.25 no.10
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• pp.1545-1550
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• 2004

meso-Functionalized dipyrromethanes 6-10 were synthesized by acid-catalyzed addition of pyrrole to ${\alpha}$-position of 2-alkenyl pyrroles. The regiochemistry of the reaction can be explained by either the formation of more stable carbocation intermediate or ${\beta}$-addition of ${\alpha},{\beta}$-unsaturated carbonyl compounds. The starting 2-alkenyl pyrroles were synthesized by Aldol condensation of 2-formylpyrrole with active methylene compounds such as nitromethane, diethylmalonate and malononitrile. Attempted ‘2+2' condensation of meso-diethylmalonyldipyrromethane, meso-(p-tolyl)dipyrromethane and p-tolualdehyde afforded three different porphyrins 12, 13 and 14 in reasonable yields. On the other hand, meso-(nitromethyl)dipyrromethane with p-(tbutyl) benzaldehyde resulted in the formation of three different porphyrins such as 5,15-dicyano-10,20-diarylporphyrin (16), 5-cyano-15-formyl-10,20-diarylporphyrin (17) and 5,15-diformyl-10,20-diarylporphyrin (18) in low yields. Conversion of nitromethyl groups to nitrile and (or) formyl group was observed under the porphyrin forming conditions.