Convergent diastereoselective preparation of adjacent quaternary stereocenters in an acyclic system.
Mejuch, Tom; Dutta, Bishnu; Botoshansky, Mark; Marek, Ilan; Organic & biomolecular chemistry 10 (2012) 5803–5806; doi:10.1039/c2ob25121c

data_7152464
_publ_section_title
;
 Convergent diastereoselective preparation of adjacent quaternary
 stereocenters in an acyclic system.
;
_journal_issue                   30
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              5803
_journal_page_last               5806
_journal_paper_doi               10.1039/c2ob25121c
_journal_volume                  10
_journal_year                    2012
_chemical_formula_sum            'C18 H26 O4'
_chemical_formula_weight         306.39
_chemical_name_common            'Marek-70 (Bishnu)'
_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
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 99.620(8)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.831(2)
_cell_length_b                   9.455(3)
_cell_length_c                   21.605(6)
_cell_measurement_reflns_used    8431
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      24.78
_cell_measurement_theta_min      1.91
_cell_volume                     1778.6(9)
_computing_cell_refinement       'DENZO HKL2000 (Otwinowski & Minor 1997)'
_computing_data_collection       'Collect (Nonius, 2006)'
_computing_data_reduction        'DENZO HKL2000 (Otwinowski & Minor 1997)'
_computing_molecular_graphics    'TEXSAN (MSC, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.840
_diffrn_measured_fraction_theta_max 0.840
_diffrn_measurement_device_type  'Nonius KappaCCD'
_diffrn_measurement_method       '\f and \w 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  0.0810
_diffrn_reflns_av_sigmaI/netI    0.0555
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            8431
_diffrn_reflns_theta_full        24.78
_diffrn_reflns_theta_max         24.78
_diffrn_reflns_theta_min         1.91
_diffrn_standards_interval_count 0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.079
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.144
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             664
_exptl_crystal_size_max          0.52
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.08
_refine_diff_density_max         0.305
_refine_diff_density_min         -0.223
_refine_diff_density_rms         0.045
_refine_ls_extinction_coef       0.040(9)
_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   0.921
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     200
_refine_ls_number_reflns         2565
_refine_ls_number_restraints     2
_refine_ls_restrained_S_all      0.954
_refine_ls_R_factor_all          0.1610
_refine_ls_R_factor_gt           0.0795
_refine_ls_shift/su_max          0.010
_refine_ls_shift/su_mean         0.002
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1599P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2151
_refine_ls_wR_factor_ref         0.2578
_reflns_number_gt                1091
_reflns_number_total             2565
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c2ob25121c.txt
_cod_data_source_block           Marek-70
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
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 1891 2012-01-12 08:04:46Z andrius 
;
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               7152464