Synthesis of substituted 1,4,5,6-tetrahydrocyclopenta[ b ]pyrroles by platinum-cata yzed cascade cyclization/ring expansion of 2-alkynyl-1-azaspiro[2. 3]hexanes
The reaction of 2-alkynyl-1-azaspiro[2.3]hexanes with a platinum catalyst is described. 1,4,5,6-Tetrahydrocyclopenta[b]pyrroles having a variety of substituents were conveniently synthesized via a cascade cyclization/ring- expansion process.