Synthesis, characterization, and crystal structures of new 3,5-diaryl-1H-pyrazoles
摘要:
Seven new 3,5-diaryl-1H-pyrazoles were synthesized by the condensation of 1,3-diketones with hydrazine in ethanol, and characterized The crystal structures for 3(5)-(4-tert-butylphenyl)-5(3)-(4-fluorphenyl)-1H-pyrazole (5) and 3-(4-tert-butylphenyl)-5-(6-methoxy-naphthalen-2-yl)-1H-pyrazole (7) have been determined by X-ray crystal structure analysis. The N-H N intermolecular hydrogen bonds join the molecules into dimers. The NH proton of 5 is disordered, and its dimer is formed by the tautomers 5a5b or 5b5a Compound 7 only exists as a 7a tautomer, and its dimer consists of the tautomers 7a7a (C) 2009 Elsevier B V All rights reserved
Five diaroylmethanatoboron difluoride derivatives were prepared from aryl methyl ketones via Claisen condensation with aromatic esters and followed by complexation with boron trifluoride etherate. Their structures and spectroscopic properties were studied by elemental analysis, IR, NMR, ESI–MS, UV and fluorescence spectroscopy. The results showed that these boron complexes had strong fluorescent peaks