rac-catena-Poly[nickel(II)-di-μ-tryptophanato]

The title complex, [Ni(C11H11N2O2)(2)](n) or [Ni(D-trp)(L-trp)](n) [D-trp = (R)-2-amino-3-(3-indolyl)propionate and L-trp = (S)-2-amino-3-( 3-indolyl)propionate], was formed by a hydrothermal method from hexaaquanickel(II) perchlorate and L-tryptophan. The Ni II atom is located on an inversion center and has an octahedral coordination geometry formed by four O atoms and two N atoms from D- and L-tryptophan ligands. Each D- and L-tryptophan ligand bridges the Ni-II atoms through the carboxylate group, leading to a two-dimensional structure parallel to the bc plane.