Single-step synthesis of 4-phenyl and 3,4-dihydro-4-phenyl coumarins using a recyclable Preyssler heteropolyacid catalyst under solvent-free reaction conditions

A. ESCOBAR; D. RUIZ; J. AUTINO; G. ROMANELLI

RESEARCH ON CHEMICAL INTERMEDIATES

SPRINGER

Lugar: Berlin; Año: 2015 vol. 41 p. 10109 - 10123

0922-6168

4-Phenyl and 3,4-dihydro-4-phenylcoumarins were prepared by direct esterification of phenols with phenylpropiolic and cinnamic acids, respectively, using acompound with Preyssler structure (H14P5NaW30O110) (PA) as heterogeneous catalyst under solvent-free reaction conditions, at 130° C, in a short reaction time (2 h). Under these conditions, very good yields (11 examples: 61-90 %), free of secondary products, were obtained. The catalyst is recyclable, nontoxic, neither air nor moisture sensitive, and easy to handle. The described methodology is a clean and useful alternativeto synthesize oxygenated heterocycles based on a coumarin skeleton.