Crystal structure of a tetrakis-substituted pyrazine compound: 2,3,5,6-tetrakis(bromomethyl)pyrazine
Assoumatine, Tokouré; Stoeckli-Evans, Helen; Acta Crystallographica Section E 70 (2014) 51–53; doi:10.1107/S1600536814011337

data_2239780
_publ_section_title
;
 Crystal structure of a tetrakis-substituted pyrazine compound:
 2,3,5,6-tetrakis(bromomethyl)pyrazine
;
_journal_coeditor_code           HB0005
_journal_issue                   8
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              51
_journal_page_last               53
_journal_paper_doi               10.1107/S1600536814011337
_journal_volume                  70
_journal_year                    2014
_chemical_formula_iupac          'C8 H8 Br4 N2'
_chemical_formula_moiety         'C8 H8 Br4 N2'
_chemical_formula_sum            'C8 H8 Br4 N2'
_chemical_formula_weight         451.80
_chemical_name_systematic
;
2,3,5,6-Tetrakis(bromomethyl)pyrazine
;
_space_group_crystal_system      tetragonal
_space_group_IT_number           92
_symmetry_space_group_name_Hall  'P 4abw 2nw'
_symmetry_space_group_name_H-M   'P 41 21 2'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2013
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   9.6858(4)
_cell_length_b                   9.6858(4)
_cell_length_c                   26.5116(17)
_cell_measurement_reflns_used    5000
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      25.95
_cell_measurement_theta_min      2.24
_cell_volume                     2487.2(2)
_computing_cell_refinement       'CELL in IPDS-I (Stoe & Cie, 2004)'
_computing_data_collection       'EXPOSE in IPDS-I (Stoe & Cie, 2004)'
_computing_data_reduction        'INTEGRATE in IPDS-I (Stoe & Cie, 2004)'
_computing_molecular_graphics    'Mercury (Macrae <i>et al.</i>, 2008)'
_computing_publication_material
;
SHELXL2013 (Sheldrick, 2008), PLATON (Spek, 2009) and
publCIF (Westrip, 2010)
;
_computing_structure_refinement  'SHELXL2013 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device       '1 ircle goniometer'
_diffrn_measurement_device_type  'Stoe IPDS 1'
_diffrn_measurement_method       '\f rotation'
_diffrn_radiation_monochromator  'plane graphite'
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.1126
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       32
_diffrn_reflns_limit_l_min       -32
_diffrn_reflns_number            19463
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.948
_diffrn_reflns_theta_min         2.239
_exptl_absorpt_coefficient_mu    12.910
_exptl_absorpt_correction_T_max  1.0000
_exptl_absorpt_correction_T_min  0.4304
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
'(<i>MULscanABS</i> in <i>PLATON</i>; Spek, 2009)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    2.413
_exptl_crystal_description       rod
_exptl_crystal_F_000             1680
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.30
_refine_diff_density_max         0.693
_refine_diff_density_min         -0.535
_refine_ls_abs_structure_details
;
Flack <i>x</i> determined using 419 quotients
[(I^+^)-(I^-^)]/[(I^+^)+(I^-^)]
(Parsons & Flack, 2004)
;
_refine_ls_abs_structure_Flack   0.04(4)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.843
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     127
_refine_ls_number_reflns         2417
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.843
_refine_ls_R_factor_all          0.0951
_refine_ls_R_factor_gt           0.0433
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0401P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0836
_refine_ls_wR_factor_ref         0.0955
_reflns_number_gt                1276
_reflns_number_total             2417
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            hb0005sup1.cif
_cod_data_source_block           I
_cod_original_cell_volume        2487.2(3)
_cod_database_code               2239780
_cod_database_fobs_code          2239780
_shelx_hkl_checksum              70757
_shelx_res_checksum              44290
_shelxl_version_number           2.013