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DOI: 10.1055/s-2004-820020
Regioselective Rapid Analogue Syntheses of 1-Methyl-3,5-diarylpyrazoles via Palladium-catalysed Coupling to 3(5)-Pyrazolyl Nonaflates
Publication History
Publication Date:
04 March 2004 (online)
Abstract
Regioselective rapid analogue syntheses of 1-methyl-3,5-diarylpyrazoles were developed, based on Pd-catalysed couplings to 1-methyl-3(5)-arylpyrazole nonaflates, which offered an advantage in hydrolytic stability over the corresponding triflates. The new bifunctional reagent 1-methyl-3-bromo-pyrazol-5-yl nonaflate underwent highly chemoselective Pd-catalysed couplings to the nonaflate, followed by Suzuki couplings to the bromide, allowing sequential, regioselective introduction of the two aryl substituents.
Key words
regioselectivity - chemoselectivity - palladium - cross-coupling - heterocycles
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References
New address: I. Collins, CRUK Centre for Cancer Therapeutics, The Institute for Cancer Research, 15 Cotswold Road, Sutton, Surrey SM2 5NG, U.K.