Oxidative Kinetic Resolution of cis-Fused Tricyclic 1-Tetralone Derivatives by Guanidine–Bisurea Bifunctional Organocatalyst

Abstract

We present an enantioselective synthesis of cis-fused tricyclic 1-tetralones via oxidative kinetic resolution in the presence of cumene hydroperoxide (CHP) and guanidine–bisurea bifunctional organocatalyst. This reaction affords the corresponding α-hydroxylation products together with unreacted tetralones in good to high enantioselectivity, with s values as high as 42. The reaction was successfully applied for the synthesis of the core structure of a kainoid derivative, 4-(2-methoxyphenyl)-2-carboxy-3-pyrrolidineacetic acid (MFPA).