An Fe(iii)-catalyzed reduction radical tandem strategy to access poly-substituted β-alkenyl valerolactones

Abstract

The convenient synthesis of structurally diverse and complex poly-substituted β-alkenyl valerolactones is first reported via the reduction radical tandem strategy of 2,3-dienoates and allyl alcohols by Fe(III)-catalysis. Under Fe(III) catalysis, various allyl alcohols can simultaneously transform into alkyl radicals and allyl ester intermediates, which can form products via Michael addition. Interestingly, the method can also prepare spiro-valerolactones and cyclo-valerolactones. In addition, β-alkenyl valerolactones can be further transformed into unreported pyrazole lactone compounds.