General synthesis of thiophene and selenophene-based heteroacenes.
Okamoto, Toshihiro; Kudoh, Kenichi; Wakamiya, Atsushi; Yamaguchi, Shigehiro; Organic letters 7 (2005) 5301–5304; doi:10.1021/ol0523650

data_1506769
_publ_section_title
;
 General synthesis of thiophene and selenophene-based heteroacenes.
;
_journal_issue                   23
_journal_name_full               'Organic letters'
_journal_page_first              5301
_journal_page_last               5304
_journal_paper_doi               10.1021/ol0523650
_journal_volume                  7
_journal_year                    2005
_chemical_formula_sum            'C16 H8 Se4'
_chemical_formula_weight         516.06
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yab'
_symmetry_space_group_name_H-M   'P 1 21/a 1'
_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                 101.258(7)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.632(8)
_cell_length_b                   7.864(4)
_cell_length_c                   14.964(10)
_cell_measurement_reflns_used    4275
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      27.4835
_cell_measurement_theta_min      3.0677
_cell_volume                     1457.9(15)
_computing_molecular_graphics    'ORTEP 3 for windows'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.963
_diffrn_measured_fraction_theta_max 0.963
_diffrn_measurement_device_type  'Rigaku Mercury diffractometer'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71070
_diffrn_reflns_av_R_equivalents  0.0719
_diffrn_reflns_av_sigmaI/netI    0.0575
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            8281
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         3.07
_exptl_absorpt_coefficient_mu    10.050
_exptl_absorpt_correction_T_max  1.0000
_exptl_absorpt_correction_T_min  0.8763
_exptl_absorpt_correction_type   empirical
_exptl_crystal_colour            red
_exptl_crystal_density_diffrn    2.351
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             960
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.20
_refine_diff_density_max         2.496
_refine_diff_density_min         -1.337
_refine_diff_density_rms         0.197
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.085
_refine_ls_hydrogen_treatment    none
_refine_ls_matrix_type           full
_refine_ls_number_parameters     181
_refine_ls_number_reflns         2467
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.085
_refine_ls_R_factor_all          0.0521
_refine_ls_R_factor_gt           0.0510
_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^)+(0.0644P)^2^+9.6846P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1309
_refine_ls_wR_factor_ref         0.1320
_reflns_number_gt                2368
_reflns_number_total             2467
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol0523650si20050930_091958.cif
_cod_data_source_block           compound_2d
_cod_original_cell_volume        1457.8(15)
_cod_original_sg_symbol_H-M      P21/a
_cod_database_code               1506769