Diels-Alder reactions of [alpha]-cyano [alpha],[beta]-unsaturated ketones with 2-methyl-1,3-butadiene: DFT study of mechanism, reactivity and regioselectivity

• Published in: Progress in reaction kinetics and mechanism Vol. 40; no. 2
• Main Authors: Nouri, Azita, Zahedi, Ehsan, Jafari, Fateme Joneydi, Nouri, Arezu
• Format: Journal Article
• Language: English
• Published: London Sage Publications Ltd 01.04.2015
• ISSN: 1468-6783; 1471-406X
• DOI: 10.3184/146867815X14262620270642

The mechanism, reactivity and regioselectivity of Diels-Alder cycloaddition reactions of 2-methyl-1,3-butadiene with four dienophiles, (E)-2-benzylidene-3-oxobutanenitrile, (E)-2-(furan-2-ylmethylene)-3-oxopentanenitrile, (E)-2-benzylidene-4,4-dimethyl-3-oxopentanenitrile, and (E)-2-benzoyl-3-(furan-2-yl) acrylonitrile, have been studied by means of several theoretical approaches. The regioselectivity of these reactions has been confirmed by their activation energies, the Gazquez-Mendez rule, Houk's rule and global descriptors of the products. All the studied reactions have normal electron demand character and a polar nature. All calculations were done at the DFT-B3LYP/6-31G(d) level of theory.