The use of mechanistic information to develop a new, catalytic multicomponent reaction is described. The complex [(salph)Al(THF)2+[co(CO)4]-(1, salph = N,N-o-phenylenebis(3,5-di-tert-butylsalicylideneimine), THF = tetrahydrofuran), wich is known to carbonylate epoxides, aziridines, and B-lactones, was used to catalyze the synthesis of 1,3-oxazinane-2,4-diones from epoxides, isocyanates, and CO. Under optimized conditions, the reaction was both selective and high-yielding. 1,3-Oxazinane-2,4-diones were synthesized from a variety of epoxides and isocyanates, including some epoxides that do not undergo simple ring-expansion carbonylation. The best results were obtained using highly electrophilic isocyanates. The mechanism of the multicomponent reaction was investigated using labeling and stereochemsitry, and the data obtained were consistent with the 1-catalyzed formation of B-lactone and 1,3-oxazinane-2,4-dione from a common intermediate.
2007. Vol. 129, no 26, 8156-8162 p.