A multicomponent double Mannich reaction of amines, aldehydes and ketones was efficiently catalyzed by molecular iodine, producing a series of 4-piperidones in a stereoselective way. A variety of amines, aldehydes and...A multicomponent double Mannich reaction of amines, aldehydes and ketones was efficiently catalyzed by molecular iodine, producing a series of 4-piperidones in a stereoselective way. A variety of amines, aldehydes and ketones were tolerated in this tandem process, including those with labile functinal groups. Further investigation of the reaction between alkyl-imines and ketones showed that imines from amines and ketones were formed in situ and isomerized to enamine in the presence of molecular iodine to accelerate the corresponding Mannich addition.展开更多
文摘A multicomponent double Mannich reaction of amines, aldehydes and ketones was efficiently catalyzed by molecular iodine, producing a series of 4-piperidones in a stereoselective way. A variety of amines, aldehydes and ketones were tolerated in this tandem process, including those with labile functinal groups. Further investigation of the reaction between alkyl-imines and ketones showed that imines from amines and ketones were formed in situ and isomerized to enamine in the presence of molecular iodine to accelerate the corresponding Mannich addition.