Tetrabutylammonium Fluoride Promoted Intramolecular Nucleophilic Attack of an Ester Group on a Carbodiimide: Preparation of 1,3-Oxazolin-5-ones and 3,1-Benzoxazin-4-ones - Molina, P; Aller, E; Écija, M; Lorenzo, A (Synthesis, 1996)