Intramolecular [3 + 2]-Cycloadditions of Azomethine Ylides Derived from Secondary Amines via Redox-Neutral C–H Functionalization
作者:Kempegowda Mantelingu、Yingfu Lin、Daniel Seidel
DOI:10.1021/ol502918g
日期:2014.11.21
Azomethine ylides are accessed under mild conditions via benzoic acid catalyzed condensations of 1,2,3,4-tetrahydroisoquinolines or tryptolines with aldehydes bearing a pendent dipolarophile. These intermediates undergo intramolecular [3 + 2]-cycloadditions in a highly diastereoselective fashion to form polycyclic amines with four new stereogenic centers. Challenging substrates such as piperidine,
An intramolecular Diels–Alder reaction involving fulvenes as 4π components—stereoselective synthesis of novel oxatricyclo[6.4.0.02,10] dodeca-2,11-diene ring system
作者:S Manikandan、M Shanmugasundaram、R Raghunathan
DOI:10.1016/s0040-4020(01)01174-7
日期:2002.1
Fulvenes acting as 4π components in an intramolecular [4+2] cycloaddition reaction leading to the formation of novel 6-oxatricyclo [6.4.0.02,10] dodeca-2,11-diene ring systems have been described. Importance of steric buttressing effect in promoting the reaction has been discussed.