Alternative Syntheses of the New D~2d~ Symmetric Tetramethyl Tricyclo- [3.3.0.0^3,7^]octane-1,3,5,7-tetracarboxylate
Carles Ayats; Pelayo Camps; María D. Duque; Mercé Font-Bardia; M. Rosa Muñoz; Xavier Solans; Santiago Vázquez; Journal of Organic Chemistry 68 (2003) 8715–8718; doi:10.1021/jo035062x

data_4022550
_publ_section_title
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 Alternative Syntheses of the New D~2d~ Symmetric
 Tetramethyl Tricyclo- [3.3.0.0^3,7^]octane-1,3,5,7-tetracarboxylate
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_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              8715
_journal_page_last               8718
_journal_paper_doi               10.1021/jo035062x
_journal_volume                  68
_journal_year                    2003
_chemical_formula_sum            'C16 H20 O8'
_chemical_formula_weight         340.32
_space_group_IT_number           70
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-F 2uv 2vw'
_symmetry_space_group_name_H-M   'F d d d :2'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   12.707(4)
_cell_length_b                   13.653(2)
_cell_length_c                   19.07(2)
_cell_measurement_temperature    293(2)
_cell_volume                     3308(4)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.226
_diffrn_measured_fraction_theta_max 0.226
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.0521
_diffrn_reflns_av_sigmaI/netI    0.0575
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       4
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_number            2451
_diffrn_reflns_theta_full        29.99
_diffrn_reflns_theta_max         29.99
_diffrn_reflns_theta_min         2.44
_exptl_absorpt_coefficient_mu    0.110
_exptl_crystal_density_diffrn    1.366
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             1440
_refine_diff_density_max         0.257
_refine_diff_density_min         -0.191
_refine_diff_density_rms         0.046
_refine_ls_extinction_expression Fc
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.994
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     76
_refine_ls_number_reflns         1212
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.994
_refine_ls_R_factor_all          0.1246
_refine_ls_R_factor_gt           0.0509
_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^)+(0.0727P)^2^+0.5812P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1212
_refine_ls_wR_factor_ref         0.1477
_reflns_number_gt                620
_reflns_number_total             1212
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo035062xsi20030723_075949.cif
_cod_data_source_block           pchc261
_cod_depositor_comments
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The following automatic conversions were performed:

'_symmetry_cell_setting' tag value 'Orthorho,bic' was replaced with
'orthorhombic' value as specified in the replacement file
'/home/robertas/cod-tools/perl-scripts/inputs/replacement_values.lst'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0727P)^2^+0.5812P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to
'w=1/[\s^2^(Fo^2^)+(0.0727P)^2^+0.5812P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_sg_symbol_H-M      'F d d d'
_cod_database_code               4022550