The Crystal-Structure of Bis[Aquabis(4-amino-3,5,6-trichloropyridine-2-carboxylato)silver(I)] Dihydrate

Abstract

The crystal structure of the silver(I) complex of the herbicide Picloram, silver(1) 4-amino- 3,5,6-trichloropyridine-2-carboxylate dihydrate, has been determined by X-ray diffraction at 293 K, and refined to a residual R 0.037 for 2583 observed reflections. The triclnic crystal has the cell dimensions a 7.1197(8), b 8.924(2), c 9.493(1) Å, α 95.84(1), β 105.71(1), γ 108.68(1)º, with space group P1, and contains one dimer per unit cell. Silver has a distorted tetrahedral coordination and is bound to the pyridyl nitrogen [Ag-N, 2.313(3) Å], an oxygen of the carboxy group [Ag-O, 2.362(2) Å], and one water molecule [Ag-O, 2.195(3) Å]. The carboxyl oxygen atoms bridge two silver atoms [Ag-O′, 2.810(2) Å] forming a centrosymmetric dimer . The other water molecule is present as a molecule of solvation , hydrogen-bonded to the amino group of the picloramate ligand [O-N, 2.881(4) Å].