Stereoselectivity in Diels−Alder Reactions of Diene-Substituted <i>N</i>-Alkoxycarbonyl-1,2-dihydropyridines
作者:Grant R. Krow、Qiuli Huang、Steven W. Szczepanski、Fredrick H. Hausheer、Patrick J. Carroll
DOI:10.1021/jo0700575
日期:2007.4.1
and stereochemical outcomes of uncatalyzed Diels−Alder reactions of N-alkoxycarbonyl-1,2-dihydropyridines with both styrene and methyl vinyl ketone (MVK) were studied. Alkyl substitution on the diene in all cases examined resulted in a kinetic preference for 7-endo isomers (7-phenyl 51−96% exo and 7-acetyl 54−96% exo). For both dienophiles, the highest stereoselectivities (≥89% endo) were observed with