Rhodium-catalyzed synthesis of 3-hydroxy-beta-lactams via oxonium ylide generation: three-component reaction between azetidine-2,3-diones, ethyl diazoacetate, and alcohols.

ABSTRACT

3-Substituted-3-hydroxy-beta-lactams, with two new adjacent stereogenic centers, have been prepared in a single step by a rhodium-catalyzed, three-component reaction between azetidine-2,3-diones, ethyl diazoacetate, and alcohols. Good to moderate stereoselectivity was obtained depending on the alcohol used. The stereochemistry of the new centers has been undoubtedly assigned by single crystal X-ray diffraction.