Quinoxalino[2,3-c]cinnolines and Their 5-N-Oxide: Alkoxylation of Methyl-Substituted Quinoxalino[2,3-c]cinnolines to Acetals and Orthoesters
Makhluf J. Haddadin; Mirna El-Khatib; Tharallah A. Shoker; Christine M. Beavers; Marilyn M. Olmstead; James C. Fettinger; Kelli M. Farber; Mark J. Kurth; Journal of Organic Chemistry 76 (2011) 8421–8427; doi:10.1021/jo201687x

data_4026668
_publ_section_title
;
 Quinoxalino[2,3-c]cinnolines and Their 5-N-Oxide: Alkoxylation of
 Methyl-Substituted Quinoxalino[2,3-c]cinnolines to Acetals and
 Orthoesters
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              8421
_journal_page_last               8427
_journal_paper_doi               10.1021/jo201687x
_journal_volume                  76
_journal_year                    2011
_chemical_formula_moiety         'C14 H8 N4 O'
_chemical_formula_sum            'C14 H8 N4 O'
_chemical_formula_weight         248.24
_chemical_name_common            'Compound 10a'
_chemical_name_systematic
; 
 quinoxalino[2,3-c]cinnoline-5-N-oxide 
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                84.733(4)
_cell_angle_beta                 83.587(4)
_cell_angle_gamma                79.155(3)
_cell_formula_units_Z            4
_cell_length_a                   7.1044(3)
_cell_length_b                   11.6958(5)
_cell_length_c                   13.3132(5)
_cell_measurement_reflns_used    8914
_cell_measurement_temperature    90(2)
_cell_measurement_theta_max      30.55
_cell_measurement_theta_min      2.94
_cell_volume                     1076.82(8)
_computing_cell_refinement       'SAINT 7.16 (Bruker, 2005)'
_computing_data_collection       'Apex2 (Bruker, 2005)'
_computing_data_reduction        'SAINT 7.16 (Bruker, 2005)'
_computing_molecular_graphics    'SHELXTL 5.1, XP (Sheldrick, 2008)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      90(2)
_diffrn_detector_area_resol_mean 8.3
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'Bruker ApexII'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0159
_diffrn_reflns_av_sigmaI/netI    0.0180
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            16218
_diffrn_reflns_theta_full        30.00
_diffrn_reflns_theta_max         30.00
_diffrn_reflns_theta_min         2.93
_exptl_absorpt_coefficient_mu    0.103
_exptl_absorpt_correction_T_max  0.962
_exptl_absorpt_correction_T_min  0.956
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Bruker, 2007)'
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    1.531
_exptl_crystal_description       block
_exptl_crystal_F_000             512
_exptl_crystal_size_max          0.44
_exptl_crystal_size_mid          0.38
_exptl_crystal_size_min          0.37
_refine_diff_density_max         0.521
_refine_diff_density_min         -0.231
_refine_diff_density_rms         0.058
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.043
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     343
_refine_ls_number_reflns         6232
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.043
_refine_ls_R_factor_all          0.0487
_refine_ls_R_factor_gt           0.0430
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0830P)^2^+0.2219P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1264
_refine_ls_wR_factor_ref         0.1305
_reflns_number_gt                5426
_reflns_number_total             6232
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            jo201687x_si_001.cif
_cod_data_source_block           cb77
_cod_database_code               4026668