Rapid construction of the aza-propellane core of acutumine via a photochemical [2 + 2] cycloaddition reaction.
Synthetic efforts toward the chlorinated aza-propellane alkaloid acutumine (1) are described. The key vicinal quaternary centers were constructed by a photochemical [2 + 2] cycloaddition reaction of a furanyl-tetrahydroindolone. Dihydroxylation of the [2 + 2] product enabled a tandem retro-aldol/intramolecular ketalization reaction, which revealed the aza-propellane core of 1 while generating an unusual, caged, pentacyclic hemiketal product.
The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Raul
R
Navarro
Sarah E
SE
Reisman
D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D001372:Aza Compounds / Q000737:chemistry*; D003500:Cyclization; D015394:Molecular Structure; D032841:Sinomenium / Q000737:chemistry; D013141:Spiro Compounds / Q000138:chemical synthesis* / Q000737:chemistry
D000470:Alkaloids; D001372:Aza Compounds; D013141:Spiro Compounds; C442344:acutumine