Synthesis and Crystal Structures of Three Pyrazine-2-carboxylate Containing Isostructural Complexes: M(2-pyrazine-carboxylate)3 (M = Co+3, Cr+3, and Rh+3)

Abstract

Three new isostructural coordination complexes, M(pca)3, where M = Co (1), Cr (2), or Rh (3) and 2-pyrazine-carboxylate (pca), have been synthesized solvothermally and characterized by single crystal X-ray diffraction and powder X-ray diffraction. In structures 1-3, the pca ligand chelates to the metal centers in a tris-chelating arrangement through proximal nitrogen and oxygen donor atoms. Structures 1-3 are monoclinic and crystallize in the space group C2/C. In structure 1, a = 28.066(13) A, b = 8.036(4) A, c = 13.577(6) A, and β = 90.2(10)°. In structure 2 a = 28.318(3) A, b = 8.089(4) A, c = 13.792(12) A, and β = 90.256(2)°. In structure 3, a = 28.679(4) A, b = 8.051(13) A, c=13.847(2) A, and β = 90.585(2)°. Three new isostructural coordination complexes, M(pca)3, where M = Co, Cr, or Rh and 2-pyrazine-carboxylate (pca), have been synthesized solvothermally and characterized by single crystal X-ray diffraction and powder X-ray diffraction.