High-throughput crystallization and crystal structure of N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)-2-methylbenzamide: a benzamide bearing the 4-aminoantipyrine moiety

A recent communication on Ru-catalyzed C-H bond arylation with 4-aminoantipyrine (AP) reported the synthesis of AP benzamides. In order to provide additional support to the published structures of AP benzamides, crystallization by high-throughput (HTP) encapsulated nanodroplet crystallization (ENaCt) was undertaken. This allowed for conclusive structure determination by single-crystal X-ray diffraction analysis (SCXRD). This article describes the crystallization and X-ray crystal structure of N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)-2-methylbenzamide, C₁₉H₁₉N₃O₂, as a benzamide bearing 4-aminoantipyrine, providing structural confirmation. X-ray structure analysis reveals intermolecular hydrogen-bonding interactions between the AP benzamide N-H proton and the carbonyl O atom of the AP moiety.