1394330-63-2Relevant articles and documents
Palladium-catalyzed direct arylation of 5-chloropyrazoles: A selective access to 4-aryl pyrazoles
Yan, Tao,Chen, Lu,Bruneau, Christian,Dixneuf, Pierre H.,Doucet, Henri
, p. 7659 - 7664 (2012/10/29)
The use of a temporary protection by a chloro group at C5 of pyrazoles allows the synthesis of the 4-arylated pyrazoles, which were previously inaccessible by palladium-catalyzed direct arylation, with complete regioselectivity and in high yields using in most cases as little as 0.5-0.1 mol % Pd(OAc)2 as the catalyst with electron-deficient aryl bromides. Moreover, from 5-chloro-1,3-dimethylpyrazole, sequential catalytic C4 arylation, dechlorination, catalytic C5 arylation reactions allowed the synthesis of a 4,5-diarylated pyrazole derivative.