Copper (I) species associated with 1, 10-phenanthroline are generated from copper (0) precursors by chemical oxidation by the aryl halides (via electron transfer) or from copper (II) precursors by chemical reduction by N-or O-nucleophiles in the presence of a base. The mechanism of cross-coupling reactions between ArX (X= I, Br, Cl) and N-or O-nucleophiles catalyzed by copper (I) ligated to 1, 3-diketonate ligands (generated from 2- ...