engleski

Photochemistry of o-Pyrrolylstilbenes and Formation of Spiro-2H-Pyrroles and Their Rearrangement to Dihydroindoles

Excited states of stilbenylpyrroles 1a-1c deactivate by two photochemical processes: cis-trans isomerization and hydrogen transfer of NH to stilbene double bond. NH-transfer results in the formation of two quinone dimethane intermediates, 10 and 11, and biradicals 12. Intramolecular cyclization of intermediates 10-12 gives rise to polycyclic compounds: spiro-2H-pyrroles 7, pyrroloisoindoles 3 and pyrroloisoquinolines 8. Spiro-2H-pyrroles 7 rearrange on silica gel giving dihydroindoles 2.

photochemistry; pyrroles; stilbenes

nije evidentirano