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_4026669
_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         'C17 H14 N4 O2'
_chemical_formula_sum            'C17 H14 N4 O2'
_chemical_formula_weight         306.32
_chemical_name_common            'Compound 11'
_chemical_name_systematic
; 
 10-(Dimethoxymethyl)quinoxalino[2,3-c]cinnoline 
;
_space_group_IT_number           33
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2n'
_symmetry_space_group_name_H-M   'P n a 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   28.7457(18)
_cell_length_b                   11.6165(8)
_cell_length_c                   4.2085(3)
_cell_measurement_reflns_used    4057
_cell_measurement_temperature    90(2)
_cell_measurement_theta_max      67.74
_cell_measurement_theta_min      4.10
_cell_volume                     1405.32(16)
_computing_cell_refinement       'SAINT (7.68A) (Bruker, 2009)'
_computing_data_collection       'Apex2 (2010-11.3) (Bruker, 2010)'
_computing_data_reduction        'SAINT (7.68A) (Bruker, 2009)'
_computing_molecular_graphics    'SHELXTL 5.1, XP (Sheldrick, 1994)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      90(2)
_diffrn_measured_fraction_theta_full 0.985
_diffrn_measured_fraction_theta_max 0.986
_diffrn_measurement_device_type  'Bruker APEX-II DUO CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0409
_diffrn_reflns_av_sigmaI/netI    0.0432
_diffrn_reflns_limit_h_max       34
_diffrn_reflns_limit_h_min       -34
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       4
_diffrn_reflns_limit_l_min       -5
_diffrn_reflns_number            7334
_diffrn_reflns_theta_full        68.16
_diffrn_reflns_theta_max         68.16
_diffrn_reflns_theta_min         3.07
_exptl_absorpt_coefficient_mu    0.808
_exptl_absorpt_correction_T_max  0.9607
_exptl_absorpt_correction_T_min  0.8474
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details   'SADABS 2008/2 (Sheldrick, 2008)'
_exptl_crystal_colour            Orange
_exptl_crystal_density_diffrn    1.448
_exptl_crystal_description       Rod
_exptl_crystal_F_000             640
_exptl_crystal_size_max          0.21
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.171
_refine_diff_density_min         -0.196
_refine_diff_density_rms         0.041
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.2(3)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.106
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     264
_refine_ls_number_reflns         2384
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.106
_refine_ls_R_factor_all          0.0478
_refine_ls_R_factor_gt           0.0454
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0977P)^2^+0.0184P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1290
_refine_ls_wR_factor_ref         0.1314
_reflns_number_gt                2243
_reflns_number_total             2384
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo201687x_si_002.cif
_cod_data_source_block           jf2006f
_cod_database_code               4026669