Regio- and Stereoselectivity in the Ene Reaction of N-Phenyl-1,2,4-triazoline-3,5-dione with α,β-Unsaturated Carbonyl Substrates

Article abstract of DOI:10.1021/jo01310a007

N-Phenyltriazoline-3,5-dione reacts with α,β-unsaturated ketones,esters, and lactones 1a-l to give ene adducts 2a-l.The reactions usually proceed in good yield with high regioselectivity and, where possible, high stereoselectivity.Ene substrates capable of adopting an s-cis conformation show much greater reactivity.A variety of mechanistic interpretations is considered.