‘On-water’ generation of carbonyl ylides from diazoamides: rhodium(II) catalyzed synthesis of spiroindolo-oxiranes and -dioxolanes with an interesting diastereoselectivity

Abstract

The ‘on-water’ generation of carbonyl ylide dipoles from diazoamides in the presence of rhodium(II) acetate dimer as the catalyst was demonstrated for the first time to synthesize spiroindolo-oxiranes and -dioxolanes. Unusual generation of carbonyl ylides with aromatic aldehydes having electron-withdrawing substituents and 1,3-dipolar cycloaddition reactions with aromatic aldehydes having electron-donating substituents were described in water with complete diastereoselectivity. This discovery provides an environmentally friendly way to generate carbonyl ylide dipoles and to synthesize substituted spiro-heterocycles in water with stereoselectivity, avoiding the use of toxic halogenated organic solvents.