Selective Synthesis of Isochromene Fused Indenone or Indane Fused Indanone Derivatives Featuring with Solvent-Dependent Intra- or Intermolecular O–H Bond Carbene Insertion

Presented herein is a condition-controlled selective synthesis of isochromene fused indenone (3) or Indane fused indanone derivatives (4) via the cascade reactions of 3-phenyl[1,2,3]triazolo[1,5-a]pyridine (1) with diazo indanedione (2). The formation of products is initiated by Rh(III)-catalyzed aryl C–H alkylation of 1 with 2 followed by denitrogenation of the pyridotriazole moiety to form a Rh-carbene species as the key intermediate. When the reaction is carried out in DCM, the Rh-carbene species undergoes an intramolecular O–H bond insertion with the enol moiety followed by proto-demetalation to give product 3. When the reaction is carried out in HFIP, on the other hand, the Rh-carbene species chooses to…

• NN
  National Natural Science Foundation of China

  Award: U2004189
• HE
  Higher Education Discipline Innovation Project

  Award: D17007
• HK
  Henan Key Laboratory of Organic Functional Molecules and Drug Innovation