Stabilization of copper(I) by phosphinoamines

Tetradentate phosphinoamines N,N?-bis[2-(diphenylphosphino)phenyl]ethane-1,2-diamine (H2dpen) and N,N?-bis[2-(diphenylphosphino)phenyl]propane-1,3-diamine stabilize copper(I) complexes either by ligand-exchange reactions from labile [CuI(MeCN)4]+ or ligand-promoted reduction of a CuII Cl2·2H2O precursor; the structure of one of the products, [Cu(H2dpen)]BF4, has been determined.