ERIC Number: EJ1062257
Record Type: Journal
Publication Date: 2015-Feb
Abstractor: As Provided
Reference Count: 8
Synthesis of 3-Methyl-4-(4-methylbenzoyl)-1-phenyl-pyrazol-5-One: How to Avoid O-Acylation
Kurteva, Vanya B.; Petrova, Maria A.
Journal of Chemical Education, v92 n2 p382-384 Feb 2015
In this laboratory experiment, students synthesize 3-methyl-4-(4-methylbenzoyl)-1-phenyl-pyrazol-5-one by selective C-acylation of 3-methyl-1-phenyl-1H-pyrazol-5-one. Calcium hydroxide is used to push the tautomeric equilibrium toward the enol form, to protect the hydroxyl functionality as a complex, to trap the liberated hydrogen chloride, and to keep the reaction media basic. The product is obtained in excellent yield and recrystallized from various solvents and solvent systems. The chromatographic and physical parameters are determined and the results are analyzed. The signals in the NMR spectra of acyl pyrazolone are assigned and then compared with those of three previously synthesized acyl pyrazolones and two corresponding O-acylated products.
Descriptors: Science Instruction, Science Experiments, Laboratory Experiments, Science Laboratories, College Science, Undergraduate Study, Chemistry, Spectroscopy, Hands on Science, Scientific Concepts
Division of Chemical Education, Inc and ACS Publications Division of the American Chemical Society. 1155 Sixteenth Street NW, Washington, DC 20036. Tel: 800-227-5558; Tel: 202-872-4600; e-mail: firstname.lastname@example.org; Web site: http://pubs.acs.org/jchemeduc
Publication Type: Journal Articles; Reports - Descriptive
Education Level: Higher Education; Postsecondary Education
Authoring Institution: N/A