Singlet‐Oxygen‐Initiated Tandem Transformation of 2‐Hexylfuran to the Natural Alkaloids Glochidine and Glochidicine
A synthesis of the imidazole alkaloids glochidine and glochidicine is presented. These natural products were prepared by the photooxygenation of a readily accessible alkylfuran precursor using histamine as a nitrogen source. By tailoring the choice of the photosensitizer as well as the conditions used for the cyclization of an N-acyliminium intermediate, the tandem reaction sequence could be manipulated to afford each of the natural products independently and as desired.