Example：10.1021/acsami.1c06204 or Chem. Rev., 2007, 107, 2411-2502
Weakly Coordinating tert-Amide-Assisted Ru(II)-Catalyzed Synthesis of Azacoumestans via Migratory Insertion of Quinoid Carbene: Application in the Total Synthesis of Isolamellarins Organic Letters (IF6.072), Pub Date : 2022-06-23, DOI: 10.1021/acs.orglett.2c01556 Souradip Sarkar, Rajarshi Samanta
A weakly coordinating tert-amide-directed straightforward method was developed for the synthesis of azacoumestans using the corresponding azaheterocycle derivatives and diazonaphthoquinones under cheap Ru(II)-catalyzed conditions. The reaction proceeds via migratory insertion of quinoid carbene and subsequent Brønstead acid-mediated cyclization. The optimized C2-selective method offered a wide scope of important azaheterocycles. Bioactive natural products like isolamellarins A and B were synthesized via the developed protocol. Preliminary mechanistic studies highlighted the probable mechanistic pathway.