| Abstract: | Two new borate compounds, C4H10N2·B6O8(OH)2 1 and (NH3CH2CH2NH3)B5O8(OH)2, have been solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, elemental analysis and thermal analysis. Compound 1 crystallizes in the monoclinic system, space group P21/c, with a = 8.3318(17), b = 6.2118(12), c = 12.479(3) (A), β = 108.96(3)°, V = 610.8(2) (A)3, Mr = 313.02, Z = 2, Dc= 1.702 g/cm3, μ = 0.150 mm-1, F(000) = 320, R = 0.0387and wR = 0.0924. Its layered structure is linked by infinite covalently coordinated neutral sheets with 3,20-membered window system, which are built up from alternative B6O8(OH)2 subunits donated by two piperzazine nitrogen donors. 2 crystallizes in monoclinic, space group Cc, with a =6.7207(13), b = 11.481(2), c = 12.564(3) (A),β = 95.25(3)°, V= 965.4(3) (A)3, Mr= 261.18, Z= 4, Dc=1.797 g/cm3, μ = 0.164 mm-1, F(000) = 536, R = 0.0396 and wR = 0.0752. Its oxoborate structure is generated from the sheets of 3,9-membered boron rings bonded diamine molecules through electrostatic and H-bonding interactions to form a two-dimensional layered network. |
