Facile synthesis of alkynyl-, aryl- and ferrocenyl-substituted pyrazoles via Sonogashira and Suzuki-Miyaura approaches

Date

2016-10-01

Author

KARABIYIKOĞLU, Sedef
Zora, Metin

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

180
views

0
downloads

A concise and efficient synthesis of densely substituted novel pyrazoles with alkynyl, aryl and ferrocenyl functionalities is reported, providing a platform for biological studies. The general strategy involves Sonogashira and Suzuki-Miyaura cross-coupling reactions of easily obtainable 5-ferrocenyl/phenyl-4-iodo-1-phenylpyrazoles with terminal alkynes and boronic acids, respectively. The starting 4-iodopyrazoles were synthesized by electrophilic cyclization of alpha,beta-alkynic hydrazones with molecular iodine. Sonogashira reactions have been achieved by employing 5 mol% PdCl2(PPh3)(2), 5 mol% CuI, excess Et3N and 1.2 equiv. of terminal alkyne, relative to 4-iodopyrazole, in tetrahydrofuran at 65 degrees C, while Suzuki-Miyaura reactions have been accomplished using 5 mol% PdCl2(PPh3)(2) and 1.4 equiv. of both boronic acid/ester and KHCO3, with respect to 4-iodopyrazole, in 4:1 dimethylformamide-H2O solution at 110 degrees C. Both Sonogashira and Suzuki-Miyaura coupling reactions have proven effective for the synthesis of alkynyl-, aryl- and ferrocenyl-substituted pyrazoles and demonstrated good tolerance to a diverse range of substituents, including electron-donating and electron-withdrawing groups. These coupling approaches could allow for the rapid construction of a library of functionalized pyrazoles of pharmacological interest. Copyright (C) 2016 John Wiley & Sons, Ltd.

Subject Keywords

Coupling, Boronic acid, Alkyne, Coupling, Boronic acid, Alkyne, Ferrocene

URI

https://hdl.handle.net/11511/47159

Journal

APPLIED ORGANOMETALLIC CHEMISTRY

DOI

https://doi.org/10.1002/aoc.3516

Collections

Department of Chemistry, Article

Suggestions

OpenMETU
Core

Selective synthesis of N-substituted pyrrolo[1,2-a]pyrazin-1(2H)-one derivatives via alkyne cyclization Cetinkaya, Yasin; Balcı, Metin (2014-12-03) A novel and efficient synthesis of N-substituted pyrrolo-pyrazinone derivatives has been developed. A trichloroacetyl group connected to the pyrrole ring was converted into the desired carboxamide derivatives. Promoted by NaH, the pyrrole carboxamide derivatives underwent a tandem reaction with propargyl bromide to afford pyrrolo-pyrazinones with high efficiency under very mild conditions. The mechanism for the formation of the products is discussed and supported by DFT calculations. (C) 2014 Elsevier Ltd. ...
Selenium containing conducting polymer based pyranose oxidase biosensor for glucose detection Gokoglan, Tugba Ceren; SÖYLEMEZ, SANİYE; Kesik, Melis; Toksabay, Sinem; Toppare, Levent Kamil (2015-04-01) A novel amperometric pyranose oxidase (PyOx) biosensor based on a selenium containing conducting polymer has been developed for the glucose detection. For this purpose, a conducting polymer; poly(4,7-bis(thieno[3,2-b]thiophen-2-yl)benzo[c][1,2,5] selenadiazole) (poly(BSeTT)) was synthesized via electropolymerisation on gold electrode to examine its matrix property for glucose detection. For this purpose, PyOx was used as the model enzyme and immobilised via physical adsorption technique. Amperometric detect...
Dimethyl ether, diethyl ether & ethylene from alcohols over tungstophosphoric acid based mesoporous catalysts Ciftci, Aysegul; VARIŞLI, DİLEK; Tokay, Kenan Cem; Sezgi, Naime Aslı; Doğu, Timur (2012-10-01) Tungstophosphoric acid (TPA) incorporated silicate structured new mesoporous catalysts were synthesized following one-pot hydrothermal and impregnation procedures. Surface area of TPA@MCM-41, which was prepared by impregnating TPA into MCM-41, was two orders of magnitude higher than the surface area of pure TPA and this catalyst showed very high activity in dehydration reactions of both ethanol and methanol. Ethanol fractional conversion values reaching to 1.0 was obtained at 300 degrees C at a space time o...
HYPERTHERMOPHILIC HYDROGEN PRODUCTION BY GEOGLOBUS ACETIVORANS IN MICROBIAL ELECTROLYSIS CELLS Kaş, Aykut; Yılmazel Tokel, Yasemin Dilşad; Department of Environmental Engineering (2021-9-10) Utilization of hyperthermophilic microorganisms was suggested to improve reaction rates and insoluble pollutant degradation and minimize the risk of contamination in bioelectrochemical systems (BESs). So far only a small group of hyperthermophilic microorganisms were identified, which show the ability to donate electrons to solid electrodes in BESs and here we present a new culture that fits to this description. The iron reducing archaeal culture Geoglobus acetivorans, originally isolated from a hydrotherma...
Enantioselective aza-Henry reaction of t-boc protected imines and nitroalkanes with bifunctional squaramide organocatalysts Susam, Dilşad; Tanyeli, Cihangir; Department of Chemistry (2015) The first part of this thesis comprises the application of a Cinchona alkaloid derived, bifunctional squaramide organocatalyst in the aza-Henry reaction of t-Boc protected imines and nitroalkanes. The target chiral β-nitroamines are chosen because; they are quite feasible for the corresponding α-amino acids and 1,2-diamines, which are basic structural motif in many natural products and key materials of the many pharmaceuticals. In this part, 12 different chiral β-nitroamine derivatives were synthesized with...

Citation Formats

S. KARABIYIKOĞLU and M. Zora, “Facile synthesis of alkynyl-, aryl- and ferrocenyl-substituted pyrazoles via Sonogashira and Suzuki-Miyaura approaches,” APPLIED ORGANOMETALLIC CHEMISTRY, pp. 876–885, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47159.