Intermolecular addition of alcohols to carbodiimides catalyzed by rare-earth metal amides

Abstract

A novel catalytic behavior of simple rare-earth metal amides RE[N(SiMe₃)₂]₃ (RE = La(1), Nd(2), Sm(3), Yb(4), Y(5)) in the intermolecular addition of alcohols to carbodiimides was disclosed. A series of isoureas were obtained in good to excellent yields via the addition reaction in the presence of the optimal lanthanum amide La[N(SiMe₃)₂]₃. Kinetic studies were also conducted and a possible mechanism of catalytic transformation was suggested.