

SYNTHESIS OF 4-ARYL(HETARYL)PYRAZOLO[1,5-a]PYRAZINES BY PALLADIUM-CATALYZED SUZUKI–MIYAURA CROSS COUPLING

Abstract
4-Bromopyrazolo[1,5-a]pyrazines react with aryl(hetaryl)boronic acids in the presence of catalytic amounts of Pd(dppf)Cl2·CH2Cl2 and an excess of Cs2CO3 in the MeCN–H2O, 9:1 solvent system with the formation of 4-aryl(hetaryl)pyrazolo[1,5-a]pyrazines.
Keywords
arylboronic acids; 4-aryl(hetaryl)pyrazolo[1,5-a]pyrazines; 4-bromopyrazolo[1,5-a]pyrazines; palladium catalysis; Suzuki– Miyaura reaction.
Latvian Institute of Organic Synthesis - Aizkraukles iela, 21, Riga, LV-1006, Latvia - hgs@osi.lv