Preparation of 3-azabicyclo [3.2.0] heptenones by intramolecular [2+2] cycloaddition
作者:Fariba Arya、James Bouquant、Josselin Chuche
DOI:10.1016/s0040-4039(00)84409-3
日期:1986.1
Pyrolysis of N-allyl enaminoesters is a general method for the stereoselective synthesis of 3-azabicyclo[3.2.0] heptenones ; the reaction involves a [2+2] intramolecularcycloaddition of an intermediate iminoketene.
Assembly of Four Diverse Heterocyclic Libraries Enabled by Prins Cyclization, Au-Catalyzed Enyne Cycloisomerization, and Automated Amide Synthesis
作者:Jiayue Cui、David I. Chai、Christopher Miller、Jason Hao、Christopher Thomas、JingQi Wang、Karl A. Scheidt、Sergey A. Kozmin
DOI:10.1021/jo301061r
日期:2012.9.7
simple one-flask operation starting with readily available amines, ketoesters, and unsaturated anhydrides. The use of tetrahydropyran-containing ketoesters, which were rapidly assembled by our Prinscyclization protocol, enabled efficient fusion of pyran and piperidinone cores. A newly developed Au(I)-catalyzed cycloisomerization of alkyne-containing enamides further expanded heterocyclic diversity by
The b-keto ester undergoes condensation reactions with aliphatic and aromatic amines in ethanol to give high-yielding b-enamino ester. The method is simple, cost-effective and environmentally benign. Structural characterization of the synthesized compounds was carried out by spectroscopic methods (1H NMR, 13C NMR and DEPT).