Preparation of Cyclic Carbodiimides – DMAP as Catalyst

P. Molina, M. Alajarin, and P. Sanchez-Andrada, Tetrahedron Lett., 34, 5155, (1993)

1. The bis(iminophsophorane) (1), DMAP, dry dichloromethane, and a slight excess of di-tert-butyldicarbonate (Boc₂O) are stirred at room temperature to afford the cyclic carbodiimide (2) in 98% yield.