• Title/Summary/Keyword: Pyrroles

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Versatilities of Calix[4]pyrrole Based Anion Receptors

  • Lee, Chang-Hee
    • Bulletin of the Korean Chemical Society
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    • v.32 no.3
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    • pp.768-778
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    • 2011
  • Calixpyrroles and related macrocycles are non-planer synthetic anion receptors that have attracted considerable attentions in recent years. Although the synthesis of calix[4]pyrrole (known as meso-octamethylporphyrinogen) was reported more than 100 years ago, the anion binding properties were first discovered in 1996. The simple calix[4]pyrroles can be synthesized in single step in high yield by condensation of pyrrole with acetone. The compounds showed preferential binding for halide anions including fluoride, phosphate, carboxylate, and chloride in organic media. Efforts to improve the anion affinity of calix[4]pyrrole and to enhance its selectivity have led to the synthesis of a variety of new calixpyrrole derivatives. Among the various modifications, introduction of straps on one side of the calix[4]pyrroles are the most effective. Incorporation of aromatic rings other than pyrroles also exhibited interesting binding behaviour. Introduction of signalling units as part of the strapping element enable to detect the anions on chromogenic or fluorogenic fashion. Finding of the anion transport properties across the membrane and cytotoxic effects of the calix[4]pyrroles open new window for calixpyrrole-related research. The polymer-incorporated systems have also been employed as anion complexants in solvent-solvent extraction. These old, yet easy-to-make macrocycles have well advanced more recently with the discovery of the ion-pair complexation properties. In this review, the synthetic developments and anion binding properties of calixpyrroles for the last decades will be discussed and will cover the advances in calixpyrrole chemistry.

Facile Regiocontrolled Three-Step Synthesis of Poly-Substituted Furans, Pyrroles, and Thiophenes: Consecutive Michael Addition of Methyl Cyanoacetate to α,β-Enone, CuI-Mediated Aerobic Oxidation, and Acid-Catalyzed Paal-Knorr Synthesis

  • Kim, Se-Hee;Lim, Jin-Woo;Lim, Cheol-Hee;Kim, Jae-Nyoung
    • 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.

Synthesis of 6-Alkoxy-3-(1-hydroxyalkyl)-5-nitro-4,5,6,7-terahydroindole-4-carboxylates

  • 김호현;구양모;이윤영
    • Bulletin of the Korean Chemical Society
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    • v.20 no.8
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    • pp.929-934
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    • 1999
  • 2-( β-Alkoxyvinyl)-4-(1-hydroxyalkyl)pyrroles (14) were synthesized from 4-acylpyrrole-2-carboxylates (8) by sequential reduction of their acyl and alkoxycarbonyl groups to give 4-(1-hydroxyalkyl)pyrrole-2-carbalde-hydes (13) followed by Wittig reaction of the aldehydes with the ylide of alkoxymethylphosphonium chloride. Diels-Alder reaction of 2-(β-alkoxyvinyl)-4-(1-hydroxyalkyl)pyrroles with trans-methyl β-nitroacrylate gave 6-alkoxy-3-(1-hydroxyalkyl)-5-nitro-4,5,6,7-tetrahydroindole-4-carboxylates (3).

The Carbazole Synthesis From 1,4-Dichloro-1,4-dimethoxybutane (1,4-디클로로-1,4-디메톡시부탄올 이용한 카르바졸의 합성)

  • Chung Bong Young;Duck Jong Bae;xJung-Il 배덕종;Seung Dal Lee
    • 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.

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Thallium(I)-Selective Electrodes Based on Calix[4]pyrroles

  • Park, Gyeong Sun;Jeong, Seong Uk;Lee, Sim Seong;Kim, Jae Sang
    • 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+.