Multicomponent and Domino Processes for the syntheses of highly functionalized cyclohexanones, piperidinones and their derivatives
Final Report Abstract
To our delight, we were able to develop a protocol for the first one-step photochemical formation of dihydropyrroles under flow conditions starting from vinyl azides and activated alkenes. Within this context the photodenitrogenation of vinyl azides to 2H-azirines using a photoflow reactor was investigated and compared with the thermal formation of 2H-azirines. Photochemically, the 2H- azirines were ring-opened to the nitrile ylides which underwent [3+2]-cycloaddition with 1,3-dipolarophiles. With this method, we were able to prepare a variety of dihydropyrroles and the electronic properties are of little importance for the principal outcome of the reaction. Notable, when diisopropylazodicarboxylate served as dipolarophile 1,3,4-triazoles became directly accessible starting from the corresponding vinyl azide.
