A convenient and general method for the synthesis of cyclic and acyclic imides, sulfonimides, and N-benzyloxycarbonyl amides via the inter-and intramolecular trapping of ketenes has been developed. Heating the corresponding amido, sulfonamido, and carbamamido ethyl ethynyl ethers at 150° C for 3 h produced the desired compounds in good to excellent yields. Key words: ketenes, imides, sulfonimides, N-benzyloxycarbonyl ...
[Kocienski, Philip J.; Pelotier, Beatrice; Pons, Jean-Marc; Prideaux, Heather Journal of the Chemical Society - Perkin Transactions 1, 1998 , # 8 p. 1373 - 1382]