119741-56-9Relevant academic research and scientific papers
Alkylation of 3(5)-cyano-1H-pyrazole-4-carboxylic acid esters
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, (2008/06/13)
The present invention provides a process for selectively alkylating pyrazoles comprising reacting a 3(5)-cyano-1H-pyrazole-4-carboxylic acid ester with a C4 -C8 alkene, or a C5 -C6 cycloalkene substituted at the 1-position with a C1 -C4 alkyl group, and a strong acid in a solvent which contains a strong electron withdrawing group. Also provided are new 3(5)-cyano-1H-pyrazole-4-carboxylic acid ester useful as starting materials in the process of the invention.
Alkylation Studies with 5-Cyano-1H-pyrazole-4-carboxylic Acid, Ethyl Ester
Beck, James R.,Aikins, James,Lynch, Michael P.,Rizzo, John R.,Tao, Eddie V.P.
, p. 3 - 6 (2007/10/02)
5-Cyano-1H-pyrazole-4-carboxylic acid, ethyl ester (1) was regioselectively alkylated at N-1 by tertiary carbocations utilizing sulfuric acid catalysis and relatively mild conditions.In the presence of boron trifluoride, the alkylation occured regioselectively at N-2.Reaction of 1 with alkyl halides under basic conditions resulted in mixture of the two isomers with alkylation at N-2 predominating.
