Synthesis, Structure and Thermal Properties of [HN(C2H5)3][B5O6(OH)4]

Triethylamine pentaborate, [HN(C2H5)3][B5O6(OH)4] (1), was hydrothermally synthesized and characterized by single crystal X-ray diffraction, FTIR, elemental analysis, and thermogravimetric analysis. Compound 1 was crystallized in the monoclinic system, space group P21/c with a=1.0036(2) nm, b=1.1353(2) nm, c=1.4843(3) nm, and β=106.54(3)°. It consisted of isolated borate polyanion [B5O6(OH)4]− and triethylamine cation [HN(C2H5)3]+. The anionic units, [B5O6(OH)4]−, were linked by hydrogen bonds to form a 3D supramolecular network containing large channels, in which the templating [HN(C2H5)3]+ cations were located.