|
|||||
|
|
Synthesis of Spirocyclic 1-Pyrrolines from Nitrones and Arynes through a Dearomative [3,3′]-Sigmatropic Rearrangement |
|
| Authors: | Abdullah S Alshreimi Guanqun Zhang Tyler W Reidl Ricardo L Peña Nicholas-George Koto Dr Shahidul M Islam Dr Donald J Wink Prof Laura L Anderson |
| Institution: | 1. Department of Chemistry, University of Illinois at Chicago, 845 W Taylor Street, Chicago, IL, USA
These authors contributed equally to this work.;2. Department of Chemistry, University of Illinois at Chicago, 845 W Taylor Street, Chicago, IL, USA |
| Abstract: | A dearomative 3,3′]-sigmatropic rearrangement that converts N-alkenylbenzisoxazolines into spirocyclic pyrroline cyclohexadienones has been developed by using the dipolar cycloaddition of an N-alkenylnitrone and an aryne to access these unusual transient rearrangement precursors. This cascade reaction affords spirocyclic pyrrolines that are inaccessible through dipolar cycloadditions of exocyclic cyclohexenones and provides a fundamentally new approach to novel spirocyclic pyrroline and pyrrolidine motifs that are common scaffolds in biologically-active molecules. Diastereoselective functionalization processes have also been explored to demonstrate the divergent synthetic utility of the unsaturated spirocyclic products. |
| Keywords: | dearomatization dipolar cycloaddition nitrones spirocyclic pyrroline sigmatropic rearrangement |