title: Hexadehydro-Diels-Alder (HDDA)-Enabled Carbazolyne Chemistry: Single Step, de Novo Construction of the Pyranocarbazole Core of Alkaloids of the Murraya koenigii (Curry Tree) Family.
abstract: Here we report the use of the hexadehydro-Diels-Alder (HDDA) reaction for the de novo construction of a benzenoid ring in fused polycyclic heteroaromatic carbazole (i.e., [2,3]-benzoindole) skeletons. The strategy allows creation of highly substituted benzenoids. We also describe the HDDA-enabled chemical synthesis of the natural product alkaloids mahanimbine and koenidine. Trapping of the intermediate carbazolyne with a conjugated enal, proceeding through formal [2+2] cycloaddition, 4π-electrocyclic ring opening, and 6π-electrocyclic ring-closing events, constitutes a robust method for producing pyranocarbazoles.
authors.affiliation: Department of Chemistry, 207 Pleasant Street, SE, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
authors.affiliation: Department of Chemistry, 207 Pleasant Street, SE, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Hoye