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N-methylimidazole promotes the reaction of homophthalic anhydride with imines.

ABSTRACT: 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.

SUBMITTER: Liu J

PROVIDER: S-EPMC4136697 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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N-methylimidazole promotes the reaction of homophthalic anhydride with imines.

Liu Jian J Wang Zheng Z Levin Aaron A Emge Thomas J TJ Rablen Paul R PR Floyd David M DM Knapp Spencer S

The Journal of organic chemistry 20140724 16

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 a ...[more]

PMID: 25036978

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