Phenylene–2,5-dimethylpyrazine co-oligomers: synthesis by Suzuki couplings, X-ray structures of neutral and diprotonated teraryl species and efficient blue emission
Figen Türksoy; Gregory Hughes; Andrei S. Batsanov; Martin R. Bryce; J. Mater. Chem. 13 (2003) 1554–1557; doi:10.1039/b303472k

data_7204649
_publ_section_title
;
 Phenylene--2,5-dimethylpyrazine co-oligomers: synthesis by Suzuki
 couplings, X-ray structures of neutral and diprotonated teraryl
 species and efficient blue emission
;
_journal_issue                   7
_journal_name_full               'J. Mater. Chem.'
_journal_page_first              1554
_journal_page_last               1557
_journal_paper_doi               10.1039/b303472k
_journal_volume                  13
_journal_year                    2003
_chemical_formula_moiety         'C18 H18 N4 O2'
_chemical_formula_sum            'C18 H18 N4 O2'
_chemical_formula_weight         322.36
_chemical_melting_point          453.1(10)
_chemical_name_systematic
; 
2,5-bis(6-methoxypyridin-3-yl)-3,6-dimethylpyrazine    
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 101.21(1)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   3.803(1)
_cell_length_b                   23.231(7)
_cell_length_c                   8.955(3)
_cell_measurement_reflns_used    820
_cell_measurement_temperature    120(2)
_cell_measurement_theta_max      25.36
_cell_measurement_theta_min      10.22
_cell_volume                     776.1(4)
_computing_cell_refinement       'SMART version 5.060 (Bruker, 1999)'
_computing_data_collection       'SMART version 5.060 (Bruker, 1999)'
_computing_data_reduction        'SAINT version 6.02A (Bruker, 2001)'
_computing_molecular_graphics    'SHELXTL version 5.10 (Bruker, 1997)'
_computing_publication_material  'SHELXTL version 5.10 (Bruker, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      120(2)
_diffrn_detector_area_resol_mean 8
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'SMART 1K CCD area detector'
_diffrn_measurement_method       '\w scans'
_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  0.0361
_diffrn_reflns_av_sigmaI/netI    0.0286
_diffrn_reflns_limit_h_max       4
_diffrn_reflns_limit_h_min       -4
_diffrn_reflns_limit_k_max       27
_diffrn_reflns_limit_k_min       -30
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            8090
_diffrn_reflns_theta_full        27.49
_diffrn_reflns_theta_max         27.49
_diffrn_reflns_theta_min         1.75
_exptl_absorpt_coefficient_mu    0.093
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.380
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             340
_exptl_crystal_size_max          0.53
_exptl_crystal_size_mid          0.13
_exptl_crystal_size_min          0.11
_refine_diff_density_max         0.242
_refine_diff_density_min         -0.195
_refine_diff_density_rms         0.044
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.028
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     145
_refine_ls_number_reflns         1774
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.028
_refine_ls_R_factor_all          0.0498
_refine_ls_R_factor_gt           0.0401
_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^)+(0.0514P)^2^+0.2846P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0988
_refine_ls_wR_factor_ref         0.1036
_reflns_number_gt                1498
_reflns_number_total             1774
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            b303472k.txt
_cod_data_source_block           (6)
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to '/home/adriana/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1555 2011-01-17 13:19:09Z saulius 

The following automatic conversions were performed:

'_chemical_melting_point' value '179--181 C' was changed to
'453.1(10)' - it was converted from degrees Celsius(C) to Kelvins(K),
the average value was taken and precision was estimated.

Automatic conversion script
Id: cif_fix_values 1569 2011-02-09 13:29:24Z adriana 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not_measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               7204649