Journal Of Organic Chemistry
The addition of N-methylimidazole (NMI) to the reaction of homophthalic anhydride with imines such as pyridine-3-carboxaldehyde-N-trifluoroethylimine (9) reduces the amount of elimination byproduct and improves the yield of the formal cycloadduct, tetrahydroisoquinolonic carboxylate 10. Carboxanilides of such compounds are of interest as potential antimalarial agents. A mechanism that rationalizes the role of NMI is proposed, and a gram-scale procedure for the synthesis and resolution of 10 is also described.
J. Liu, Z. Wang, A. Levin, T. J. Emge, Paul R. Rablen, D. M. Floyd, and S. Knapp.
"N-Methylimidazole Promotes The Reaction Of Homophthalic Anhydride With Imines".
Journal Of Organic Chemistry.