The synthesis and structural characterisation of some azo-containing phosphine chalcogenides and comparison to non-phosphorus-containing analogues
Alder, Mark J.; Bates, Vanessa M.; Cross, Wendy I.; Flower, Kevin R.; Pritchard, Robin G.; Journal of the Chemical Society, Perkin Transactions 1  (2001) 2669–; doi:10.1039/b104918f

data_7216897
_publ_section_title
;
 The synthesis and structural characterisation of some azo-containing
 phosphine chalcogenides and comparison to non-phosphorus-containing
 analogues
;
_journal_issue                   20
_journal_name_full
'Journal of the Chemical Society, Perkin Transactions 1'
_journal_page_first              2669
_journal_paper_doi               10.1039/b104918f
_journal_year                    2001
_chemical_compound_source        'synthesis as described'
_chemical_formula_moiety         'C21 H20 N4 O1'
_chemical_formula_structural     'C21 H20 N4 O1'
_chemical_formula_sum            'C21 H20 N4 O'
_chemical_formula_weight         344.41
_space_group_IT_number           33
_symmetry_cell_setting           orthorhombic
_symmetry_Int_Tables_number      33
_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_conform_dict_location     ftp://ftp.iucr.org/cifdics/cif_core.dic
_audit_conform_dict_name         cif_core.dic
_audit_conform_dict_version      2.1
_audit_creation_date             2000-10-30T23:19:17-00:00
_audit_creation_method           'WinGX routine CIF_UPDATE'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   18.942(4)
_cell_length_b                   20.515(3)
_cell_length_c                   4.6558(10)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      11.4
_cell_measurement_theta_min      6.2
_cell_measurement_wavelength     1.54178
_cell_volume                     1809.2(6)
_computing_cell_refinement       'ADC6-INDEX (MSC, 1990)'
_computing_data_collection       'AFC6-COLLECT (MSC, 1990)'
_computing_data_reduction        'PROCESS (MSC, 1990)'
_computing_molecular_graphics    'Ortep-3 for Windows (Farrugia, 1997)'
_computing_publication_material  'WinGX publication routines (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.994
_diffrn_measured_fraction_theta_max 0.994
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.121
_diffrn_reflns_av_unetI/netI     0.1496
_diffrn_reflns_limit_h_max       21
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       23
_diffrn_reflns_limit_k_min       -23
_diffrn_reflns_limit_l_max       5
_diffrn_reflns_limit_l_min       -5
_diffrn_reflns_number            6653
_diffrn_reflns_theta_full        65.04
_diffrn_reflns_theta_max         65.04
_diffrn_reflns_theta_min         3.18
_exptl_absorpt_coefficient_mu    0.641
_exptl_crystal_colour            'dark orange'
_exptl_crystal_density_diffrn    1.264
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             728
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.15
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.197
_refine_diff_density_min         -0.197
_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   0.1(12)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.07
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     242
_refine_ls_number_reflns         3048
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.07
_refine_ls_R_factor_all          0.1883
_refine_ls_R_factor_gt           0.085
_refine_ls_shift/su_max          0.072
_refine_ls_shift/su_mean         0.015
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0668P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1656
_refine_ls_wR_factor_ref         0.2121
_reflns_number_gt                1228
_reflns_number_total             3048
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b104918f.txt
_cod_data_source_block           comp6
_cod_database_code               7216897