An RCM strategy to stereodiverse δ-sultam scaffolds

An asymmetric approach for the synthesis of substituted delta-sultams with multiple synthetic handles is described. This study demonstrates the facile construction of a stereochemically diverse array of substituted delta-sultams, more specifically substituted 3,4,5,6-dihydro 1,2-thiazine 1,1-dioxides. A pivotal Mitsunobu alkylation/RCM sequence is used to assemble key allyl sultam building blocks possessing a C3 stereogenic handle. All subsequent reactions are achieved with high levels of diastereoselectivity to afford enantiopure delta-sultams in good yields.