Structure of the caffeine-pyrogallol complex: revisiting a pioneering structural analysis of a model pharmaceutical cocrystal.
Al Rahal, Okba; Ferguson, Michael; Lennox, Cameron B.; Male, Louise; Friščić, Tomislav; Chemical communications (Cambridge, England) 60 (2024) 7431–7434; doi:10.1039/d4cc02289k

data_7133128
_publ_section_title
;
 Structure of the caffeine-pyrogallol complex: revisiting a pioneering
 structural analysis of a model pharmaceutical cocrystal.
;
_journal_issue                   58
_journal_name_full               'Chemical communications (Cambridge, England)'
_journal_page_first              7431
_journal_page_last               7434
_journal_paper_doi               10.1039/d4cc02289k
_journal_volume                  60
_journal_year                    2024
_chemical_formula_moiety         'C8 H10 N4 O2, C6 H6 O3, 4(H2 O)'
_chemical_formula_sum            'C14 H24 N4 O9'
_chemical_formula_weight         392.37
_space_group_crystal_system      tetragonal
_space_group_IT_number           86
_space_group_name_Hall           '-P 4bc'
_space_group_name_H-M_alt        'P 42/n :2'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     dual
_audit_creation_date             2024-04-26
_audit_creation_method
;
Olex2 1.5
(compiled 2024.02.16 svn.r378c4104 for OlexSys, GUI svn.r6928)
;
_audit_update_record
;
2024-04-26 deposited with the CCDC.	2024-06-03 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   23.1123(5)
_cell_length_b                   23.1123(5)
_cell_length_c                   6.8449(2)
_cell_measurement_reflns_used    6810
_cell_measurement_temperature    120.01(10)
_cell_measurement_theta_max      76.9950
_cell_measurement_theta_min      5.3890
_cell_volume                     3656.40(15)
_computing_cell_refinement       'CrysAlisPro 1.171.42.81a (Rigaku OD, 2023)'
_computing_data_collection       'CrysAlisPro 1.171.42.81a (Rigaku OD, 2023)'
_computing_data_reduction        'CrysAlisPro 1.171.42.81a (Rigaku OD, 2023)'
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2019/3 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT 2018/2 (Sheldrick, 2018)'
_diffrn_ambient_environment      N~2~
_diffrn_ambient_temperature      120.01(10)
_diffrn_detector                 'CCD plate'
_diffrn_detector_area_resol_mean 10.3537
_diffrn_detector_type            Atlas
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.984
_diffrn_measurement_details
;
List of Runs (angles in degrees, time in seconds):

  # Type    Start    End  Width  t~exp~   \w     \q     \k     \f   Frames
  1  \w    -68.00  31.00   1.00    4.79    --  -41.27  51.00  43.00   99
  2  \w    101.00 178.00   1.00   19.16    --  112.00  72.00-120.00   77
  3  \w     39.00 109.00   1.00   19.16    --  112.00-111.00  28.00   70
  4  \w      6.00  81.00   1.00    4.79    --   41.27 -99.00-150.00   75
  5  \w     17.00 116.00   1.00    4.79    --   41.27  38.00-120.00   99
  6  \w    103.00 178.00   1.00   19.16    --  112.00  77.00   0.00   75
  7  \w     39.00 138.00   1.00   19.16    --  112.00 -45.00 -60.00   99
  8  \w    104.00 178.00   1.00   19.16    --  112.00 111.00 -30.00   74
  9  \w    104.00 178.00   1.00   19.16    --  112.00 111.00 122.00   74
 10  \w     13.00 114.00   1.00    4.79    --   41.27  57.00 120.00  101
 11  \w     13.00  38.00   1.00    4.79    --   41.27  57.00 -60.00   25
 12  \w     13.00 114.00   1.00    4.79    --   41.27  57.00   0.00  101
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'SuperNova, Dual, Cu at home/near, Atlas'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_type
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      -0.0534345000
_diffrn_orient_matrix_UB_12      -0.0363685000
_diffrn_orient_matrix_UB_13      0.0547683000
_diffrn_orient_matrix_UB_21      0.0051912000
_diffrn_orient_matrix_UB_22      0.0205964000
_diffrn_orient_matrix_UB_23      0.2134320000
_diffrn_orient_matrix_UB_31      -0.0394854000
_diffrn_orient_matrix_UB_32      0.0519108000
_diffrn_orient_matrix_UB_33      -0.0462257000
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0403
_diffrn_reflns_av_unetI/netI     0.0309
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 0.984
_diffrn_reflns_limit_h_max       28
_diffrn_reflns_limit_h_min       -29
_diffrn_reflns_limit_k_max       26
_diffrn_reflns_limit_k_min       -24
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            19300
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 0.984
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         77.311
_diffrn_reflns_theta_min         3.825
_diffrn_source                   'micro-focus sealed X-ray tube'
_diffrn_source_type              'SuperNova (Cu) X-ray Source'
_exptl_absorpt_coefficient_mu    1.029
_exptl_absorpt_correction_T_max  1.000
_exptl_absorpt_correction_T_min  0.765
_exptl_absorpt_correction_type   gaussian
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.42.81a (Rigaku Oxford Diffraction, 2023)
Numerical absorption correction based on gaussian integration over
a multifaceted crystal model
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.426
_exptl_crystal_description       Rod
_exptl_crystal_F_000             1664
_exptl_crystal_size_max          0.434
_exptl_crystal_size_mid          0.098
_exptl_crystal_size_min          0.06
_refine_diff_density_max         0.254
_refine_diff_density_min         -0.340
_refine_diff_density_rms         0.052
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.057
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     293
_refine_ls_number_reflns         3825
_refine_ls_number_restraints     2
_refine_ls_restrained_S_all      1.056
_refine_ls_R_factor_all          0.0630
_refine_ls_R_factor_gt           0.0447
_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^)+(0.0476P)^2^+2.7291P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1080
_refine_ls_wR_factor_ref         0.1211
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2998
_reflns_number_total             3825
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d4cc02289k2.cif
_cod_data_source_block           caf-pyg-4H2O
_cod_depositor_comments
'Adding full bibliography for 7133127--7133128.cif.'
_cod_original_cell_volume        3656.40(19)
_cod_original_sg_symbol_H-M      'P 42/n'
_cod_database_code               7133128
_shelx_shelxl_version_number     2019/3
_chemical_oxdiff_formula         'C11 H10 N O'
_shelx_estimated_absorpt_t_max   0.941
_shelx_estimated_absorpt_t_min   0.664
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups
 At 1.5 times of:
  All C(H,H) groups, All C(H,H,H) groups, All O(H,H) groups
2. Restrained distances
 O9-H9B
 0.95 with sigma of 0.02
 O9A-H9AA
 0.95 with sigma of 0.02
3. Others
 Sof(O9A)=Sof(H9AA)=Sof(H9AB)=1-FVAR(1)
 Sof(O9)=Sof(H9A)=Sof(H9B)=FVAR(1)
4.a Free rotating group:
 O6(H6D,H6E), O7(H7A,H7B), O8(H8A,H8B), O9(H9A,H9B), O9A(H9AA,H9AB)
4.b Aromatic/amide H refined with riding coordinates:
 C2(H2), C12(H12), C13(H13), C14(H14)
4.c Idealised Me refined as rotating group:
 C1(H1A,H1B,H1C), C4(H4A,H4B,H4C)
;
_shelx_res_checksum              59531
_shelx_hkl_checksum              45554
_olex2_submission_special_instructions 'No special instructions were received'
_oxdiff_exptl_absorpt_empirical_details
;
Empirical correction (ABSPACK) includes:
- Absorption correction using spherical harmonics
- Frame scaling
;
_oxdiff_exptl_absorpt_empirical_full_max 1.827
_oxdiff_exptl_absorpt_empirical_full_min 0.663