Hydro-thermal synthesis and crystal structure of a new lanthanum(III) coordination polymer with fumaric acid.

The title compound, poly[di-aqua-tris-(μ4-but-2-enedioato)(μ2-but-2-enedioic acid)dilanthanum(III)], [La2(C4H2O4)3(C4H4O4)(H2O)2] n , was synthesized by the reaction of lanthanum chloride penta-hydrate with fumaric acid under hydro-thermal conditions. The asymmetric unit comprises an La(III) cation, one and a half fumarate dianions (L (2-)), one a half-mol-ecule of fumaric acid (H2 L) and one coordinated water mol-ecule. Each La(III) cation has the same nine-coordinate environment and is surrounded by eight O atoms from seven distinct fumarate moieties, including one proton-ated fumarate unit and one water mol-ecule in a distorted tricapped trigonal-prismatic environment.

2-Amino-3-carb-oxy-pyridinium perchlorate.

The asymmetric unit includes two crystallographically independent equivalents of the title salt, C(6)H(7)N(2)O(2) (+)·ClO(4) (-). The cations and anions form separate layers alternating along the c axis, which are linked by N-H⋯O, O-H⋯O and C-H⋯O hydrogen bonds into a two-dimensional network parallel to (100). Further C-H⋯O contacts connect these layers, forming a three-dimensional network, in which R(4) (4)(20) rings and C(2) (2)(11) infinite chains can be identified.