Aquabis(2,2′-bipyridine-κ 2 N , N ′)(1 H -indole-2-carboxylato-κ O )nickel(II) 1 H -indole-2-carboxylate dihydrate

The hydro­thermal reaction of Ni2(OH)2CO3 with 2,2′-bipyridine and 2-indolyl-formic acid in CH3OH/H2O at 423 K for 7 d produced the novel NiII complex [Ni(C9H6NO2)(C10H8N2)2(H2O)](C9H6NO2)·2H2O. The asymmetric unit of the title compound consists of a monovalent [Ni(L)(bpy)2(H2O)]+ cation (bpy is 2,2′-bipyridine and L is 1H-indole-2-carboxyl­ate), an L anion and two solvent water mol­ecules. In the [Ni(L)(bpy)2(H2O)]+ cations, the Ni atom coordinates to four N atoms from the two bpy ligands and two O atoms, one from a L anion and the other from a water mol­ecule to complete an significantly distorted NiN4O2 octa­hedron. The coordinated and solvate water mol­ecules form an extensive series of O—H⋯O hydrogen bonds. N—H⋯O and C—H⋯O hydrogen bonds are also present and the mol­ecules are inter­linked, forming a three-dimensional network.