New synthetic route to the alkaloid withasomnine by ring transformation of a functionalized cyclopropanol via the parent pyrrolo[1,2-b]pyrazole

Article abstract of DOI:10.1016/0040-4039(95)02313-5

Withasomnine has been prepared by rearrangement of 1-(3-chloropropyl)-cyclopropanol into 5,6-dihydro-4H-pyrrolo[1,2-b]pyrazole, followed by bromination and [NiCl₂(dppp)]-catalyzed phenylation.