The Rearrangement of 2, 3-Epoxysulfonates and Its Application to Natural Products Syntheses: Formal Synthesis of (-)-Aphanorphine and Total Syntheses of (-)-α- …
The Lewis acid treatment of 2, 3-epoxysulfonates with 2, 3-dialkyl substituents or 2-alkyl-3- aryl substituents produced the rearrangement products via C3-cleavage of the oxirane ring in high yields. On the other hand, 2-aryl-3-alkyl-2, 3-epoxysulfonates produced the products via C2-cleavage of the oxirane ring. The sulfonyloxy groups of the α-sulfonyloxy ketones, having a chiral benzylic quaternary carbon center obtained by the rearrangement of 2- ...