M. Toyota et al., AN EFFICIENT SYNTHESIS OF 1,2,3,4-TETRASUBSTITUTED PYRROLES VIA INTRAMOLECULAR AZOMETHINE YLIDE [3-DIPOLAR CYCLOADDITION(2]), Heterocycles, 39(1), 1994, pp. 39-42
A sequence of reactions, involving intramolecular azomethine ylide [32] dipolar cycloaddition, was used to efficiently construct 1,2,3,4-te
trasubstituted pyrroles.