Stereoselective synthesis of 5-alkyliden-6-aminotetrahydro-2-pyranones through an unexpected isomerization of the hydroxytetrahydro-2-pyridinones obtained by the …
A convenient methodology for the stereoselective preparation of 5-alkyliden-6- aminotetrahydro-2-pyranone 4 is reported. The synthesis of 2-pyranone 4 occurs through an unknown isomerization mechanism of the hydroxytetrahydro-2-pyridinone 3, an accessible starting material obtained by mild and selective reduction of the 5-acyltetrahydro-2- pyridinone 2. The isomerization mechanism and the stereoselectivity in the synthesis of 2- ...