<i>rac</i>-6-Hydroxy-2,5,7,8-tetramethylchroman-2-carboxamide from synchrotron data
Brzezinski, Krzysztof; Dauter, Zbigniew; Baj, Aneta; Wałejko, Piotr; Witkowski, Stanisław; Acta Crystallographica Section E 67 (2011) o503–o504; doi:10.1107/S1600536811002807

data_2229136
_publ_section_title
;
 <i>rac</i>-6-Hydroxy-2,5,7,8-tetramethylchroman-2-carboxamide from
 synchrotron data
;
_journal_coeditor_code           KP2304
_journal_issue                   2
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o503
_journal_page_last               o504
_journal_paper_doi               10.1107/S1600536811002807
_journal_volume                  67
_journal_year                    2011
_chemical_formula_iupac          'C14 H19 N O3'
_chemical_formula_moiety         'C14 H19 N O3'
_chemical_formula_sum            'C14 H19 N O3'
_chemical_formula_weight         249.31
_chemical_melting_point          492
_chemical_name_systematic
;
<i>rac</i>-6-Hydroxy-2,5,7,8-tetramethylchroman-2-carboxamide
;
_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   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.00
_cell_angle_beta                 100.430(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   9.110(10)
_cell_length_b                   17.92(2)
_cell_length_c                   15.950(10)
_cell_measurement_reflns_used    6360
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      23.51
_cell_measurement_theta_min      1.43
_cell_volume                     2561(4)
_computing_cell_refinement       'HKL2000 (Otwinowski & Minor, 1997)'
_computing_data_collection       'NECAT APS beamline software'
_computing_data_reduction        'HKL2000 (Otwinowski & Minor, 1997)'
_computing_molecular_graphics
'ORTEP-3 (Farrugia, 1997) and PyMOL (DeLano, 2002)'
_computing_publication_material  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXD (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.961
_diffrn_measured_fraction_theta_max 0.961
_diffrn_measurement_device_type  'MAR315 CCD'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  'Si111 double crystal'
_diffrn_radiation_source         'NECAT 24ID-C synchrotron beamline APS, USA'
_diffrn_radiation_type           synchrotron
_diffrn_radiation_wavelength     0.59040
_diffrn_reflns_av_R_equivalents  0.030
_diffrn_reflns_av_sigmaI/netI    0.0364
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       24
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            14016
_diffrn_reflns_theta_full        23.51
_diffrn_reflns_theta_max         23.51
_diffrn_reflns_theta_min         1.43
_exptl_absorpt_coefficient_mu    0.057
_exptl_absorpt_correction_T_max  0.997
_exptl_absorpt_correction_T_min  0.988
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SCALEPACK; Otwinowski <i>et al.</i>, 2003)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.293
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             1072
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.414
_refine_diff_density_min         -0.246
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.077
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     327
_refine_ls_number_reflns         6360
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.077
_refine_ls_R_factor_all          0.0615
_refine_ls_R_factor_gt           0.0495
_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^)+(0.0846P)^2^+0.4358P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1399
_refine_ls_wR_factor_ref         0.1469
_reflns_number_gt                5153
_reflns_number_total             6360
_reflns_threshold_expression     I>2sigma(I)
_cod_data_source_file            kp2304.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2229136
_cod_database_fobs_code          2229136