Synthesis of Weinreb amides via Pd-catalyzed aminocarbonylation of heterocyclic-derived triflates.
The direct transformation of lactam-, lactone-, and thiolactone-derived triflates into N-methoxy-N-methyl or morpholine Weinreb amides has been realized using Pd-catalyzed aminocarbonylation under CO atmospheric pressure and at room temperature. The carbonylative coupling can be efficiently carried out with 2% of catalyst in the presence of Xantphos as a ligand. The amides smoothly react with nucleophiles to afford acylated aza-, oxa-, and thio-heterocycles. The proposed methodology could be advantageously exploited for the synthesis of dienones in which one of the double bonds is embedded in a heterocyclic moiety, as useful substrates for Nazarov cyclization.
Deagostino
A
A
Dipartimento di Chimica Generale ed Organica Applicata, Università di Torino, Corso Massimo D'Azeglio, 48, I-10125 Torino, Italy.
Larini
Paolo
P
Occhiato
Ernesto G
EG
Pizzuto
Lorena
L
Prandi
Cristina
C
Venturello
Paolo
P
D000577:Amides / Q000138:chemical synthesis*; D002384:Catalysis; D006571:Heterocyclic Compounds / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D010165:Palladium / Q000737:chemistry*
D000577:Amides; D006571:Heterocyclic Compounds; D010165:Palladium