Application of reactive enols in synthesis: a versatile, efficient, and stereoselective construction of the welwitindolinone carbon skeleton

An efficient and stereoselective synthesis of the complete carbon skeleton found in several welwitindolinone alkaloids was developed. In the process of discovering the synthetic pathway, the remarkable consequences of Montmorillonite K10 clay on aryl C-H insertion reactions were noticed. The usefulness of reactive enol intermediates derived from the interaction of alpha-keto rhodium carbenoids with alcohols was further confirmed.