Amine Derivatives as Nucleophiles

Legraverend reported the coupling of a variety of amides with 2,6-dihalopurines [179] for this, he employed XantPhos as ligand and CS2CO3 as base for arylations. 

Figu re 3.17 Selected examples of amine derivatives and ligands used for their palladium-catalyzed arylations. 

Furuta and Kan reported the cyclizahon of bromosubstituted amides, yielding phenanthridinone derivatives, using their (phenyl)(naphthyl)phosphine ligands together with CS2CO3 as base [180], 

Klapars reported the synthesis of enamides by the coupling of enol tosylates with amides [181], Here, an i-propyl-derivative of dppf was used as ligand together with the weak bases K3PO4 or K2CO3 in t-AmOH as solvent. Previously, XantPhos and CS2CO3 were used for the same purpose in 1,4-dioxane as solvent by Wallace [182], 

Details of the coupling of closely related ureas and cyclic carbamates were reported using BINAP or biphenyl-based phosphine ligands with weak bases, such as CS2CO3 or K3PO4 [183]. McLaughlin reported a palladium-catalyzed urea 

---