Phenyl- and mesitylglyoxylic acids: catemeric hydrogen bonding in two α-keto acids
Chen, Chung-Der; Brunskill, Andrew P. J.; Hall, Stan S.; Lalancette, Roger A.; Thompson, Hugh W.; Acta Crystallographica Section C 56 (2000) 1148–1151; doi:10.1107/S010827010000812X

data_2011307
_publ_section_title
;
 Phenyl- and mesitylglyoxylic acids: catemeric hydrogen bonding in two
 \a-keto acids
;
_journal_issue                   9
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              1148
_journal_page_last               1151
_journal_paper_doi               10.1107/S010827010000812X
_journal_volume                  56
_journal_year                    2000
_chemical_formula_moiety         'C11 H12 O3'
_chemical_formula_sum            'C11 H12 O3'
_chemical_formula_weight         192.21
_chemical_melting_point          392
_chemical_name_common            'mesitylglyoxylic acid'
_chemical_name_systematic
;
\a-oxo-2,4,6-trimethylbenzeneacetic acid
;
_space_group_IT_number           144
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_Hall  'P 31'
_symmetry_space_group_name_H-M   'P 31'
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            3
_cell_length_a                   9.1210(10)
_cell_length_b                   9.1210(10)
_cell_length_c                   10.5760(10)
_cell_measurement_reflns_used    17
_cell_measurement_temperature    248(2)
_cell_measurement_theta_max      12.0
_cell_measurement_theta_min      5.6
_cell_volume                     761.97(14)
_computing_cell_refinement       XSCANS
_computing_data_collection       'XSCANS (Siemens, 1996)'
_computing_data_reduction        XSCANS
_computing_molecular_graphics    SHELXTL
_computing_publication_material  SHELXTL
_computing_structure_refinement  SHELXTL
_computing_structure_solution    'SHELXTL (Sheldrick, 1997)'
_diffrn_ambient_temperature      248(2)
_diffrn_measured_fraction_theta_full .987
_diffrn_measured_fraction_theta_max .987
_diffrn_measurement_device_type  'Siemens P4'
_diffrn_measurement_method       '2\q-\q scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'normal-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     .71073
_diffrn_reflns_av_R_equivalents  .046
_diffrn_reflns_av_sigmaI/netI    .057
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            2050
_diffrn_reflns_theta_full        24.99
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         2.58
_diffrn_standards_decay_%        'variation < 3.3'
_diffrn_standards_interval_count 97
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    .091
_exptl_absorpt_correction_T_max  .977
_exptl_absorpt_correction_T_min  .967
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details   '(SHELXTL; Sheldrick, 1997)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.257
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             306
_exptl_crystal_size_max          .30
_exptl_crystal_size_mid          .28
_exptl_crystal_size_min          .26
_refine_diff_density_max         .13
_refine_diff_density_min         -.18
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.02
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     141
_refine_ls_number_reflns         886
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.02
_refine_ls_R_factor_all          .088
_refine_ls_R_factor_gt           .049
_refine_ls_shift/su_max          <0.001
_refine_ls_shift/su_mean         .00
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0648P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         .127
_reflns_number_gt                574
_reflns_number_total             1772
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            fg1604.cif
_cod_data_source_block           II
_cod_database_code               2011307
_cod_database_fobs_code          2011307