The Open Organic Chemistry Journal

2008, 2 : 10-16
Published online 2008 March 10. DOI: 10.2174/1874095200801020010
Publisher ID: TOOCJ-2-10

Microwave Synthesis of Arylmethyl Substituted Pyrazoles

Consuelo Escolástico , Mercedes Blanco , Rosa M. Claramunt , Dionisia Sanz and José Elguero
Departamento de Química Orgánica y Bio-Orgánica, Facultad de Ciencias, UNED, Senda del Rey 9, E- 28040 Madrid, Spain.

ABSTRACT

The synthesis under MW irradiation without solvent of 19 pyrazoles, of which only 8 were known, is described. They bear C-methyl groups and trityl, diphenylmethyl and benzyl groups at positions 1 and 4 of the pyrazole ring. In the reaction between pyrazole and trityl bromide an unexpected reaction occurred and 4-(9-phenyl-9H-fluoren-9-yl)-1Hpyrazole (7) was isolated.

Keywords:

Microwave, pyrazoles, tritylpyrazole.