Phosphine-Mediated Sequential [2+4]/[2+3] Annulation to Construct Pyrroloquinolines
Junhui Lin, Yannan Zhu, Wei Cai, You Huang
Abstract
A domino [2+4]/[2+3] sequential annulation reaction of MBH carbonates with N-unprotected indoles has been developed to provide various pyrroloquinoline derivatives in ≤94% yield and 20:1 dr. The reaction could be either mediated by stoichiometric PCy3 or catalyzed by R3PO via PIII/PV═O redox cycling in the presence of phenylsilane. This method assembles polycyclic 1,7-fused indoles in one step diastereoselectively.
Topics & Concepts
ChemistryAnnulationYield (engineering)PhosphineDominoStoichiometryRedoxCombinatorial chemistryDehydrogenationReaction conditionsPhenylsilaneMedicinal chemistryCatalysisStereochemistryOrganic chemistryMetallurgyMaterials scienceAsymmetric Hydrogenation and CatalysisSynthesis and Catalytic ReactionsAsymmetric Synthesis and Catalysis