Racemic 5-ethyl-2,6-dimethyl-4-<i>p</i>-tolyl-3-cyclohexenecarboxylic acid: an <i>RS</i> dimer
Xie, Songwen; Kenny, Colin; Robinson, Paul D.; Acta Crystallographica Section E 63 (2007) o3897–o3897; doi:10.1107/S1600536807041098

data_2215240
_publ_section_title
;
 Racemic 5-ethyl-2,6-dimethyl-4-<i>p</i>-tolyl-3-cyclohexenecarboxylic
 acid: an <i>RS</i> dimer
;
_journal_coeditor_code           OM2154
_journal_issue                   9
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o3897
_journal_page_last               o3897
_journal_paper_doi               10.1107/S1600536807041098
_journal_volume                  63
_journal_year                    2007
_chemical_formula_iupac          'C18 H24 O2'
_chemical_formula_moiety         'C18 H24 O2'
_chemical_formula_sum            'C18 H24 O2'
_chemical_formula_weight         272.37
_chemical_melting_point          .4905E-305
_chemical_name_systematic
;
(RS)-5-ethyl-2,6-dimethyl-4-p-tolyl-3-cyclohexenecarboxylic acid
;
_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                 94.318(5)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   16.2786(14)
_cell_length_b                   11.4720(10)
_cell_length_c                   8.1035(7)
_cell_measurement_reflns_used    2703
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      28.17
_cell_measurement_theta_min      2.51
_cell_volume                     1509.0(2)
_computing_cell_refinement       'SAINT (Bruker, 2005)'
_computing_data_collection
;
APEX2 (Bruker, 2005)
;
_computing_data_reduction
;
SAINT (Bruker, 2005) and SADABS (Bruker, 2005)
;
_computing_molecular_graphics
;
PLATON (Spek, 2003)
;
_computing_publication_material
;
SHELXL97 (Sheldrick, 1997) and PLATON (Spek, 2003)
;
_computing_structure_refinement
;
LS in TEXSAN (Molecular Structure Corporation, 1997) and
SHELXL97 (Sheldrick, 1997)
;
_computing_structure_solution    'SIR92 (Altomare <i>et al.</i>,  1994)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker Kappa APEX II CCD'
_diffrn_measurement_method       '\f and \w'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'X-ray tube'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0539
_diffrn_reflns_av_sigmaI/netI    0.0361
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -20
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       6
_diffrn_reflns_limit_l_min       -9
_diffrn_reflns_number            19084
_diffrn_reflns_theta_full        25.99
_diffrn_reflns_theta_max         25.99
_diffrn_reflns_theta_min         2.17
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.076
_exptl_absorpt_correction_T_max  0.989
_exptl_absorpt_correction_T_min  0.600
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Bruker, 2005)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.199
_exptl_crystal_description       'irregular fragment'
_exptl_crystal_F_000             592
_exptl_crystal_size_max          0.41
_exptl_crystal_size_mid          0.17
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.551
_refine_diff_density_min         -0.464
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.029
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     186
_refine_ls_number_reflns         2952
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.029
_refine_ls_R_factor_all          0.0807
_refine_ls_R_factor_gt           0.0580
_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^)+(0.0587P)^2^+1.3904P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1358
_refine_ls_wR_factor_ref         0.1501
_reflns_number_gt                2211
_reflns_number_total             2952
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            om2154.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2215240
_cod_database_fobs_code          2215240