Photoredox-catalyzed intramolecular oxy- and aminoacylation of alkenes with acyl oxime esters: facile synthesis of acylated saturated heterocycles

In the present paper, an efficient photoredox-catalyzed intramolecular oxy- and aminoacylation of internal alkenes equipped with pendant oxygen- or nitrogen-centered nucleophiles with acyl oxime esters is reported. Under visible-light irradiation, a variety of structurally diverse acylated saturated heterocycles, such as tetrahydrofurans, tetrahydropyrans, delta-valerolactones, tetrahydropyrroles, piperidines, tetrahydro-1,3-oxazepines, etc., were efficiently synthesized from easily accessible unsaturated alcohols, carboxylic acids, tosyl-protected amines, and O-homoallyl benzimidates via an acyl radical-mediated cascade acylation/cyclization process. This light-driven transformation features a broad substrate scope, good functional group compatibility, high regio- and diastereoselectivity, and mild reaction conditions, representing a general and practical procedure toward the construction of acylated saturated heterocycles as well as their derivatives. A general photoredox-catalyzed intramolecular oxy- and aminoacylation of internal alkenes with acyl oxime esters to access various acyl heterocycles is developed.