TiCl4 promoted formal [3 + 3] cycloaddition of cyclopropane 1,1-diesters with azides: synthesis of highly functionalized triazinines and azetidines.

A TiCl4 promoted formal [3 + 3] cycloaddition of cyclopropane 1,1-diesters with azides has been developed for the synthesis of highly functionalized triazinines. Both stoichiometric and substoichiometric versions of this reaction were accomplished dependent on the choice of solvent. It is noteworthy that the corresponding products could be easily converted to biologically important azetidines by simple thermolysis.