Two (+)-α,4-dimethyl-2-oxocyclohexaneacetic acids: hydrogen bonding in a terpenoid γ-keto acid and in a diastereomeric lactol
Davison, Mark; Kikolski, Elizabeth M.; Mostafavi, David; Lalancette, Roger A.; Thompson, Hugh W.; Acta Crystallographica Section C 61 (2005) o249–o252; doi:10.1107/S0108270105004944

data_2014841
_publ_section_title
;
 Two (+)-\a,4-dimethyl-2-oxocyclohexaneacetic acids: hydrogen bonding
 in a terpenoid \g-keto acid and in a diastereomeric lactol
;
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              o249
_journal_page_last               o252
_journal_paper_doi               10.1107/S0108270105004944
_journal_volume                  61
_journal_year                    2005
_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          416
_chemical_name_systematic
;
(+)-(3R,3aR,6R,7aR)-hexahydro-7a-hydroxy-3,6-dimethylbenzo[a]furan-2-one'
;
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   6.728(2)
_cell_length_b                   7.455(2)
_cell_length_c                   19.829(5)
_cell_measurement_reflns_used    29
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      10.6
_cell_measurement_theta_min      1.9
_cell_volume                     994.6(5)
_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 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Siemens P4'
_diffrn_measurement_method       2\q/\q
_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  0.030
_diffrn_reflns_av_sigmaI/netI    0.042
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            2100
_diffrn_reflns_theta_full        25.04
_diffrn_reflns_theta_max         25.04
_diffrn_reflns_theta_min         2.05
_diffrn_standards_decay_%        'variation <1.6'
_diffrn_standards_interval_count 97
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.089
_exptl_absorpt_correction_T_max  0.989
_exptl_absorpt_correction_T_min  0.958
_exptl_absorpt_correction_type   analytical
_exptl_absorpt_process_details   '(SHELXS97; Sheldrick, 1997a)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.230
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             400
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.11
_refine_diff_density_min         -0.12
_refine_ls_extinction_coef       0.019(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 1997a)'
_refine_ls_goodness_of_fit_ref   1.06
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     119
_refine_ls_number_reflns         1050
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.06
_refine_ls_R_factor_all          0.057
_refine_ls_R_factor_gt           0.038
_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^)+(0.0322P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.075
_refine_ls_wR_factor_ref         0.082
_reflns_number_gt                799
_reflns_number_total             1050
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            gg1241.cif
_cod_data_source_block           II
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

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 'Orthorhombic' changed to
'orthorhombic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

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

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_database_code               2014841
_cod_database_fobs_code          2014841