The diprotonated perchlorate salt of 2,3-di-2-pyridyl-5-nitroquinoxaline [C18H13N5O2](ClO4)2·(CH3OH)·(C2H5OH) has been synthesized and characterized by elemental analysis, IR and NMR spectra. X-ray diffracti...The diprotonated perchlorate salt of 2,3-di-2-pyridyl-5-nitroquinoxaline [C18H13N5O2](ClO4)2·(CH3OH)·(C2H5OH) has been synthesized and characterized by elemental analysis, IR and NMR spectra. X-ray diffraction analysis at room temperature indicates that the title compound (C21H23N5O12Cl2, Mr = 608.34) crystallizes in triclinic, space group P 1 with a = 7.992(8), b = 12.82(1), c = 13.42(1) A, α = 104.77(2),β = 97.84(2), r= 95.48(2)°, V= 1305(2) A3, Z = 2,DC= 1.549 g/cm3, F(000) = 628 and μ(MoKα) = 0.317 mm-1. The final R and wR factors are 0.0566 and 0.1016, respectively with 4325 independent reflections. The quinoxaline ring makes the dihedral angles of 44.2(2) and 33.9(5)° with two protonated pyridine rings whose dihedral angle is 48.1(6)°. The favored orientation of two protonated pyridine rings is that thek N atoms are opposite to each other. There exist intra- and inter-molecular N-H…O hydrogen bonds and π…π interactions which stabilize the structure further.展开更多
基金This work was financially supported by NNSFC(No.29971019)
文摘The diprotonated perchlorate salt of 2,3-di-2-pyridyl-5-nitroquinoxaline [C18H13N5O2](ClO4)2·(CH3OH)·(C2H5OH) has been synthesized and characterized by elemental analysis, IR and NMR spectra. X-ray diffraction analysis at room temperature indicates that the title compound (C21H23N5O12Cl2, Mr = 608.34) crystallizes in triclinic, space group P 1 with a = 7.992(8), b = 12.82(1), c = 13.42(1) A, α = 104.77(2),β = 97.84(2), r= 95.48(2)°, V= 1305(2) A3, Z = 2,DC= 1.549 g/cm3, F(000) = 628 and μ(MoKα) = 0.317 mm-1. The final R and wR factors are 0.0566 and 0.1016, respectively with 4325 independent reflections. The quinoxaline ring makes the dihedral angles of 44.2(2) and 33.9(5)° with two protonated pyridine rings whose dihedral angle is 48.1(6)°. The favored orientation of two protonated pyridine rings is that thek N atoms are opposite to each other. There exist intra- and inter-molecular N-H…O hydrogen bonds and π…π interactions which stabilize the structure further.
