Key tricyclic synthetic intermediates for the preparation of the sesquiterpenes α- and β-cedrene
Kennedy, Alan R.; Kerr, William J.; McLaughlin, Mark; Pauson, Peter L.; Acta Crystallographica Section C 57 (2001) 1316–1318; doi:10.1107/S0108270101013336

data_2012316
_publ_section_title
;
 Key tricyclic synthetic intermediates for the preparation of the
 sesquiterpenes \a- and \b-cedrene
;
_journal_issue                   11
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              1316
_journal_page_last               1318
_journal_paper_doi               10.1107/S0108270101013336
_journal_volume                  57
_journal_year                    2001
_chemical_formula_moiety         'C16 H22 O3'
_chemical_formula_sum            'C16 H22 O3'
_chemical_formula_weight         262.34
_chemical_name_systematic
;
(3\b,3a\b,7\b)-(+-)-6,6-ethylenedioxy-3,8,8-trimethyl-2,3,3a,4,5,6,7,8-
octahydro-3a,7-methanoazulen-2-one
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_cell_angle_alpha                90
_cell_angle_beta                 107.469(15)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   6.0402(13)
_cell_length_b                   31.423(4)
_cell_length_c                   7.7111(13)
_cell_measurement_reflns_used    21
_cell_measurement_temperature    295(2)
_cell_measurement_theta_max      10.72
_cell_measurement_theta_min      7.06
_cell_volume                     1396.1(4)
_computing_cell_refinement       'MSC/AFC Diffractometer Control Software'
_computing_data_collection
;MSC/AFC Diffractometer Control Software (Molecular Structure Corporation,
 1988)
;
_computing_data_reduction
'TEXSAN (Molecular Structure Corporation, 1992)'
_computing_molecular_graphics    'ORTEPII (Johnson, 1976)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR92 (Altomare et al., 1994)'
_diffrn_ambient_temperature      295(2)
_diffrn_measured_fraction_theta_full .971
_diffrn_measured_fraction_theta_max .971
_diffrn_measurement_device_type  'Rigaku AFC-7S'
_diffrn_measurement_method       \w/2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     .71069
_diffrn_reflns_av_R_equivalents  .061
_diffrn_reflns_av_sigmaI/netI    .090
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       38
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -9
_diffrn_reflns_number            2977
_diffrn_reflns_theta_full        25.99
_diffrn_reflns_theta_max         25.99
_diffrn_reflns_theta_min         2.59
_diffrn_standards_decay_%        3.01
_diffrn_standards_interval_count 150
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    .085
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.248
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       tabular
_exptl_crystal_F_000             568
_exptl_crystal_size_max          .50
_exptl_crystal_size_mid          .40
_exptl_crystal_size_min          .15
_refine_diff_density_max         .18
_refine_diff_density_min         -.15
_refine_ls_extinction_coef       .017(2)
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 1997)'
_refine_ls_goodness_of_fit_ref   1.011
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     176
_refine_ls_number_reflns         2721
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.011
_refine_ls_R_factor_all          .126
_refine_ls_R_factor_gt           .048
_refine_ls_shift/su_max          <0.001
_refine_ls_shift/su_mean         .000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0533P)^2^+0.1589P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         .142
_reflns_number_gt                1522
_reflns_number_total             2721
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            gd1172.cif
_cod_data_source_block           IIIa
_cod_depositor_comments
;
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_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               2012316
_cod_database_fobs_code          2012316