Demonstration of 14-20-membered intramolecular carbonyl ylides: diastereoselective synthesis of macrocycles incorporating spiro-indolooxiranes

A mild route to synthesize the macrocycles incorporating spiro-indolooxiranes with complete diastereoselectivity in good yield in the presence of rhodium(II) acetate as a catalyst was demonstrated. This process demonstrates the formation of 14-20 intramolecular carbonyl ylides for the first time.