Crystal structure of 2,4,6-tri-methyl-benzoic anhydride.
Land, Michael A.; Robertson, Katherine N.; Clyburne, Jason A. C.; Acta crystallographica. Section E, Crystallographic communications 73 (2017) 1735–1738; doi:10.1107/S2056989017014670

data_2311478
_publ_section_title
;
 Crystal structure of 2,4,6-tri-methyl-benzoic anhydride.
;
_journal_coeditor_code           HB7710
_journal_issue                   'Pt 11'
_journal_name_full
'Acta crystallographica. Section E, Crystallographic communications'
_journal_page_first              1735
_journal_page_last               1738
_journal_paper_doi               10.1107/S2056989017014670
_journal_volume                  73
_journal_year                    2017
_chemical_formula_iupac          'C20 H22 O3'
_chemical_formula_moiety         'C20 H22 O3'
_chemical_formula_sum            'C20 H22 O3'
_chemical_formula_weight         310.37
_chemical_name_systematic
;
2,4,6-Trimethylbenzoic anhydride
;
_space_group_crystal_system      monoclinic
_space_group_IT_number           15
_space_group_name_Hall           '-C 2yc'
_space_group_name_H-M_alt        'C 1 2/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                90
_cell_angle_beta                 114.094(2)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   16.080(2)
_cell_length_b                   7.9997(12)
_cell_length_c                   14.308(2)
_cell_measurement_reflns_used    6207
_cell_measurement_temperature    125(2)
_cell_measurement_theta_max      28.65
_cell_measurement_theta_min      2.78
_cell_volume                     1680.2(4)
_computing_cell_refinement
;
SAINT (Bruker, 2008)
;
_computing_data_collection
;
APEX2 (Bruker, 2008)
;
_computing_data_reduction
;
SAINT (Bruker, 2008)
;
_computing_molecular_graphics
;
Mercury (Macrae <i>et al.</i>,  2008) [OK?]
;
_computing_publication_material
;
SHELXL2014 (Sheldrick, 2015b)
;
_computing_structure_refinement
;
SHELXL2014 (Sheldrick, 2015b)
;
_computing_structure_solution
;
SHELXT2014 (Sheldrick, 2015a)
;
_diffrn_ambient_temperature      125(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.950
_diffrn_measurement_device_type  'Bruker APEXII CCD area-detector'
_diffrn_measurement_method       '\f and \w'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0187
_diffrn_reflns_limit_h_max       21
_diffrn_reflns_limit_h_min       -21
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            9832
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         28.854
_diffrn_reflns_theta_min         2.775
_exptl_absorpt_coefficient_mu    0.081
_exptl_absorpt_correction_T_max  0.7458
_exptl_absorpt_correction_T_min  0.6831
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
(SADABS; Bruker, 2008)
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.227
_exptl_crystal_description       'wedge shaped (cut from a large block)'
_exptl_crystal_F_000             664
_exptl_crystal_size_max          0.550
_exptl_crystal_size_mid          0.260
_exptl_crystal_size_min          0.250
_refine_diff_density_max         0.344
_refine_diff_density_min         -0.194
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.052
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     108
_refine_ls_number_reflns         2095
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.052
_refine_ls_R_factor_all          0.0420
_refine_ls_R_factor_gt           0.0373
_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^)+(0.0543P)^2^+0.9964P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1026
_refine_ls_wR_factor_ref         0.1069
_reflns_number_gt                1857
_reflns_number_total             2095
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            hb7710sup1.cif
_cod_data_source_block           I
_cod_original_cell_volume        1680.1(4)
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               2311478
_shelx_estimated_absorpt_t_min   0.957
_shelx_estimated_absorpt_t_max   0.980
_shelx_hkl_checksum              90264
_shelx_res_checksum              27299