Highly regio- and Stereoselective Diels-Alder Cycloadditions Via Two-Step and Multicomponent Reactions Promoted by Infrared Irradiation Under Solvent-Free Conditions

Maria Ines Flores-Conde, Leonor Reyes, Rafael Herrera, Hulme Rios, Miguel A. Vazquez, Rene Miranda, Joaquin Tamariz, Francisco Delgado

Research output: Contribution to journalArticle

15 Scopus citations

Abstract

Infrared irradiation promoted the Diels-Alder cycloadditions of exo-2-oxazolidinone dienes 1-3 with the Knoevenagel adducts 4-6, as dienophiles, leading to the synthesis of new 3,5-diphenyltetrahydrobenzo[d]oxazol-2-one derivatives (7, 9, 11 and 13-17), under solvent-free conditions. These cycloadditions were performed with good regio- and stereoselectivity, favoring the para-endo cycloadducts. We also evaluated the one-pot three-component reaction of active methylene compounds 20, benzaldehydes 21 and exo-2-oxazolidinone diene 2 under the same reaction conditions. A cascade Knoevenagel condensation/Diels-Alder cycloaddition reaction was observed, resulting in the final adducts 13-16 in similar yields. These procedures are environmentally benign, because no solvent and no catalyst were employed in these processes. The regioselectivity of these reactions was rationalized by Frontier Molecular Orbital (FMO) calculations. © 2012 by the authors; licensee MDPI, Basel, Switzerland.
Original languageAmerican English
Pages (from-to)2590-2617
Number of pages28
JournalInternational Journal of Molecular Sciences
DOIs
StatePublished - 1 Mar 2012

    Fingerprint

Cite this