Palladium-Catalyzed Aerobic Oxidative Cyclization of Aliphatic Alkenyl Amides for the Construction of Pyrrolizidine and Indolizidine Derivatives
An efficient palladium-catalyzed aerobic oxidative cyclization has been developed to synthesize a variety of pyrrolizidine and indolizidine derivatives from simple aliphatic alkenyl amides in moderate to good yields. The reaction features the capability of accessing various N-heterocycles and the use of molecular oxygen (1 atm) as the green oxidant.
Lo, Kai-Yip,Ye, Liu,Yang, Dan
p. 1570 - 1575
(2017/08/11)
Radical carbonylation of ω-alkynylamines leading to α-methylene lactams. Synthetic scope and the mechanistic insights
Tin hydride mediated radical carbonylation and cyclization reaction was investigated using a variety of ω-alkynyl amines as substrates. In this reaction α-methylene and α-stannylmethylene lactams having five to eight membered rings were obtained as princi
Palladium-Catalyzed Carbonylation. A New Synthesis of α-Methylene γ-, δ-, and ε-Lactams and -Lactones Including Bicyclic Lactams of Pyrrolizidine and Indolizidine Skeletons
The insertion of carbon monoxide into vinyl halides bearing the secondary amine or alcohol with a catalytic amount of Pd(OAc)2 and PPh3 was realized to give five-, six-, and seven-membered lactams and lactones carrying α-methylene groups in fairly good yields.Bicyclic heterocycles, pyrrolizidine and indolizidine derivatives, were also synthesized from pyrrolidine and piperidine derivatives possessing vinyl halide groups in the side chain at the 2-position of the ring by means of palladium-catalyzed carbonylation.