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

The convenient synthesis of structurally diverse and complex poly-substituted beta-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, beta-alkenyl valerolactones can be further transformed into unreported pyrazole lactone compounds.

Automated summary

The convenient synthesis of diverse and complex poly-substituted beta-alkenyl valerolactones is achieved through Fe(iii)-catalyzed reduction radical tandem strategy of 2,3-dienoates and allyl alcohols. The allyl alcohols can undergo simultaneous transformations into alkyl radicals and allyl ester intermediates under Fe(iii) catalysis, which then react via Michael addition to form the desired products. Notably, this method also enables the preparation of spiro-valerolactones and cyclo-valerolactones, as well as the transformation of beta-alkenyl valerolactones into previously unreported pyrazole lactone compounds.