Facile access to functionalized spiro[indoline-3,2'-pyrrole]-2,5'-diones via post-Ugi domino Buchwald-Hartwig/Michael reaction

Org Lett. 2014 Aug 1;16(15):3884-7. doi: 10.1021/ol5019079. Epub 2014 Jul 16.

Abstract

A novel access to spiro[indoline-3,2'-pyrrole]-2,5'-diones is presented via a palladium-catalyzed post-Ugi cascade cyclization approach involving a Buchwald-Hartwig/Michael reaction sequence. The method allows the easy construction of a library of spirooxindoles in moderate to good yields starting from readily available precursors. In addition, alkynoic acids are replaced with α,β-unsaturated acids leading to variably substituted spirooxindoles.