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Stereoselective Synthesis of Tropanes via a 6?-Electrocyclic Ring-Opening/ Huisgen [3+2]-Cycloaddition Cascade of Monocyclopropanated Heterocycles.

ABSTRACT: The synthesis of tropanes via a microwave-assisted, stereoselective 6?-electrocyclic ring-opening/ Huisgen [3+2]-cycloaddition cascade of cyclopropanated pyrrole and furan derivatives with electron-deficient dipolarophiles is demonstrated. Starting from furans or pyrroles, 8-aza- and 8-oxabicyclo[3.2.1]octanes are accessible in two steps in dia- and enantioselective pure form, being versatile building blocks for the synthesis of pharmaceutically relevant targets, especially for new cocaine analogues bearing various substituents at the C-6/C-7 positions of the tropane ring system. Moreover, the 2-azabicyclo[2.2.2]octane core (isoquinuclidines), being prominently represented in many natural and pharmaceutical products, is accessible via this approach.

SUBMITTER: Sonnleitner CM

PROVIDER: S-EPMC7589232 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Stereoselective Synthesis of Tropanes via a 6π-Electrocyclic Ring-Opening/ Huisgen [3+2]-Cycloaddition Cascade of Monocyclopropanated Heterocycles.

Sonnleitner Carina M CM Park Saerom S Eckl Robert R Ertl Thomas T Reiser Oliver O

Angewandte Chemie (International ed. in English) 20200818 41

The synthesis of tropanes via a microwave-assisted, stereoselective 6π-electrocyclic ring-opening/ Huisgen [3+2]-cycloaddition cascade of cyclopropanated pyrrole and furan derivatives with electron-deficient dipolarophiles is demonstrated. Starting from furans or pyrroles, 8-aza- and 8-oxabicyclo[3.2.1]octanes are accessible in two steps in dia- and enantioselective pure form, being versatile building blocks for the synthesis of pharmaceutically relevant targets, especially for new cocaine analo ...[more]

PMID: 32627302

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