Luminescent atropisomeric N,N-chelating ligands from copper-catalyzed one-pot C-N and C-C coupling reactions.

New atropisomeric N,N-chelating ligands with a 3,3'-bis[2-(2'-py)-indolyl] unit have been achieved via one-pot reactions that involve the formation of multiple C-N bonds between an indolyl and a brominated benzene and the indolyl 3,3'-C-C coupling. The new ligands display distinct blue intramolecular excimer emission (lambda(max) = 445 nm). Cu(I) ions bind to the new N,N-chelate ligands with a homochiral selectivity. The complex [Cu(bpib)2][BF(4)] (bpib = bis{3,3'-[N-phenyl-2-(2'-py)-indolyl]}) crystallizes as chiral crystals, thus allowing enantiomeric separation.