Copper cyanide-catalyzed palladium coupling of n-tert-butoxycarbonyl-protected α-lithio amines with aryl iodides or vinyl iodides

摘要

Treatment of (α-aminoalkyl)lithium reagents with aryl iodides in the presence of catalytic amounts of CuCN and PdCl_2(PPh_3)2 or [(p-MeOC_6H_4)3P]4Pd affords 2-aryl substituted amines in modest to good yields. The yields can be improved by use of softer ligands such as AsPh_3 and SbPh_3 or by use of bis(diphenylphosphino)ferrocene (dppf). Coupled products are obtained with electron-rich aryl iodides (XarI,X-Me, Ome), and the reaction fails with electron-poor aryl iodides (XarI, X= NO_2 CO_2Li).