%0 Journal Article %T Conditions for palladium-catalyzed direct arylations of 4-bromo and 4-iodo N-substituted pyrazoles without C-Br or C-I bond cleavage %+ Institut des Sciences Chimiques de Rennes (ISCR) %+ Laboratoire de Synthèse Organique Asymétrique et Catalyse Homogène %A Brahim, Mariem %A Smari, Imen %A Ben Ammar, Hamed %A Ben Hassine, Bechir %A Soulé, Jean-François %A Doucet, Henri %< avec comité de lecture %@ 2052-4129 %J Organic Chemistry Frontiers %I Royal Society of Chemistry %V 2 %N 8 %P 917-926 %8 2015 %D 2015 %R 10.1039/c5qo00093a %Z Chemical SciencesJournal articles %X The Pd-catalyzed arylation at the C5 position of N-protected pyrazole derivs. bearing bromo or iodo substituents at the C4 position is described. A simple phosphine-free catalytic system was used, namely, 1 mol% Pd(OAc)2 in DMA in the presence of KOAc as the base. A wide aryl bromide scope as a coupling partner has been coupled with pyrazole derivs. The reaction was very chemoselective as the C-halogen bonds of the pyrazole units were not involved in the C-H bond arylation process. Some examples demonstrating the synthetic potential of the bromo and iodo pyrazole substituents for chem. transformations are reported. %G English %L hal-01162340 %U https://univ-rennes.hal.science/hal-01162340 %~ UNIV-RENNES1 %~ CNRS %~ INSA-RENNES %~ ENSC-RENNES %~ ISCR %~ SCR_OMC2012 %~ ISCR-OMC %~ STATS-UR1 %~ UR1-SPM %~ INC-CNRS %~ UR1-UFR-SPM %~ UR1-HAL %~ UR1-SDLM %~ UR1-SDLMJONCH %~ TEST-UNIV-RENNES %~ TEST-UR-CSS %~ UNIV-RENNES %~ INSA-GROUPE %~ UR1-MMS %~ TEST2-HALCNRS