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Cyclopropenimine-catalyzed enantioselective Mannich reactions of tert-butyl glycinates with N-Boc-imines.

ABSTRACT: Cyclopropenimine 1 is shown to catalyze Mannich reactions between glycine imines and N-Boc-aldimines with high levels of enantio- and diastereocontrol. The reactivity of 1 is shown to be substantially greater than that of a widely used thiourea cinchona alkaloid-derived catalyst. A variety of aryl and aliphatic N-Boc-aldimines are effective substrates for this transformation. A preparative-scale reaction to deliver >90 mmol of product is shown using 1 mol % catalyst. The products of this transformation can be converted into several useful derivatives.

SUBMITTER: Bandar JS

PROVIDER: S-EPMC3804837 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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Cyclopropenimine-catalyzed enantioselective Mannich reactions of tert-butyl glycinates with N-Boc-imines.

Bandar Jeffrey S JS Lambert Tristan H TH

Journal of the American Chemical Society 20130801 32

Cyclopropenimine 1 is shown to catalyze Mannich reactions between glycine imines and N-Boc-aldimines with high levels of enantio- and diastereocontrol. The reactivity of 1 is shown to be substantially greater than that of a widely used thiourea cinchona alkaloid-derived catalyst. A variety of aryl and aliphatic N-Boc-aldimines are effective substrates for this transformation. A preparative-scale reaction to deliver >90 mmol of product is shown using 1 mol % catalyst. The products of this transfo ...[more]

PMID: 23906087

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