Copper-Catalyzed Synthesis of Indolines

Chemler and coworkers developed a number of equivalent copper-promoted reactions that involve the intermolecular addition of amines to olefins to the synthesis of AT-heterocycles via carboamination [51-54] and deamination 

They also developed the Cu(OTf)2-catalyzed enantioselective alkene hydroamination/cyclization to enantioenriched 2-methylindolines using 1,4-cyclohexadiene as hydrogen atom source. 1,4-Cyclohexadiene is relatively 

6-di-tert-Butyl-4-methylpyridine (1 equiv.) 4A molecular sieves Toluene, 100-110 °C, 8 h 

The fused indoUnes could be synthesized from 2-ethynylarylmethylenecyclo-propane with sulfonyl azide using Cul as catalyst and EtgN as base. A ketenimine species and 6zr-electrocyclization could be involved for this transformation. The copper-catalyzed triazole intermediate formation from 2-ethynylaryl 

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Scheme 33 Copper-catalyzed synthesis of indolines and related heterocycles...

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