(<b>±</b>)-3-Ethyl-2-methyl-4-oxocyclohexanecarboxylic acid: catemeric hydrogen bonding in a cyclic δ-keto acid
Davison, Mark; Kikolski,Elizabeth M.; Lalancette, Roger A.; Thompson, Hugh W.; Acta Crystallographica Section C 60 (2004) o449–o451; doi:10.1107/S0108270104010534

data_2013990
_publ_section_title
;
 (<b>+-</b>)-3-Ethyl-2-methyl-4-oxocyclohexanecarboxylic acid:
 catemeric hydrogen bonding in a cyclic \d-keto acid
;
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              o449
_journal_page_last               o451
_journal_paper_doi               10.1107/S0108270104010534
_journal_volume                  60
_journal_year                    2004
_chemical_formula_iupac          'C10 H16 O3'
_chemical_formula_moiety         'C10 H16 O3'
_chemical_formula_sum            'C10 H16 O3'
_chemical_formula_weight         184.23
_chemical_melting_point          376
_chemical_name_systematic
;
(+-)-3-Ethyl-2-methyl-4-oxocyclohexanecarboxylic acid
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                80.425(14)
_cell_angle_beta                 85.53(2)
_cell_angle_gamma                82.67(2)
_cell_formula_units_Z            4
_cell_length_a                   5.5739(12)
_cell_length_b                   12.814(3)
_cell_length_c                   14.396(3)
_cell_measurement_reflns_used    36
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      8.9
_cell_measurement_theta_min      1.7
_cell_volume                     1003.9(4)
_computing_cell_refinement       XSCANS
_computing_data_collection       'XSCANS (Siemens, 1996)'
_computing_data_reduction        XSCANS
_computing_molecular_graphics    'SHELXP97 (Sheldrick, 1997a)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997a)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997a)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Siemens P4'
_diffrn_measurement_method       '2\q/\q scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.025
_diffrn_reflns_av_sigmaI/netI    0.039
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -1
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            4736
_diffrn_reflns_theta_full        25.05
_diffrn_reflns_theta_max         25.05
_diffrn_reflns_theta_min         1.62
_diffrn_standards_decay_%        'variation <2'
_diffrn_standards_interval_count 97
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.089
_exptl_absorpt_correction_T_max  0.982
_exptl_absorpt_correction_T_min  0.962
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details   'Sheldrick (1997)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.219
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'trapezoidal block'
_exptl_crystal_F_000             400
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.36
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.20
_refine_diff_density_min         -0.16
_refine_ls_extinction_coef       0.024(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.02
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     244
_refine_ls_number_reflns         3556
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.02
_refine_ls_R_factor_all          0.070
_refine_ls_R_factor_gt           0.048
_refine_ls_shift/su_max          0.00
_refine_ls_shift/su_mean         0.00
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0519P)^2^+0.3545P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.119
_refine_ls_wR_factor_ref         0.133
_reflns_number_gt                2587
_reflns_number_total             3556
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            fr1484.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from
2010-06-29.

'_geom_bond_publ_flag' value 'Y' changed to 'y' according to
'/home/saulius/struct/CIF-dictionaries/cif_core.dic' dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29 (4 times).

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from
2010-06-29.

'_geom_bond_publ_flag' value 'Y' changed to 'y'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29 (4
times).

'_geom_angle_publ_flag' value 'Y' changed to 'y' according
to /home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary
named 'cif_core.dic' version 2.4.1 from 2010-06-29 (4 times).

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_database_code               2013990
_cod_database_fobs_code          2013990