Highly Diastereoselective and Enantioselective Formal [4 + 1] Ylide Annulation for the Synthesis of Optically Active Dihydrofurans
Jun-Cheng Zheng; Chun-Yin Zhu; Xiu-Li Sun; Yong Tang; Li-Xin Dai; Journal of Organic Chemistry 73 (2008) 6909–6912; doi:10.1021/jo801135j

data_4023653
_publ_section_title
;
 Highly Diastereoselective and Enantioselective Formal [4 + 1]
 Ylide Annulation for the Synthesis of Optically Active Dihydrofurans
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              6909
_journal_page_last               6912
_journal_paper_doi               10.1021/jo801135j
_journal_volume                  73
_journal_year                    2008
_chemical_absolute_configuration ad
_chemical_formula_sum            'C16 H17 Br O4'
_chemical_formula_weight         353.21
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 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                 118.156(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   11.310(2)
_cell_length_b                   7.3489(13)
_cell_length_c                   11.365(2)
_cell_measurement_reflns_used    1608
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      48.487
_cell_measurement_theta_min      6.876
_cell_volume                     832.8(3)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SHELXTL'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega 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  0.1377
_diffrn_reflns_av_sigmaI/netI    0.1109
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            4376
_diffrn_reflns_theta_full        25.50
_diffrn_reflns_theta_max         25.50
_diffrn_reflns_theta_min         2.03
_exptl_absorpt_coefficient_mu    2.480
_exptl_absorpt_correction_T_max  1.0000
_exptl_absorpt_correction_T_min  0.6512
_exptl_absorpt_correction_type   empirical
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.409
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             360
_exptl_crystal_size_max          0.497
_exptl_crystal_size_mid          0.411
_exptl_crystal_size_min          0.213
_refine_diff_density_max         1.200
_refine_diff_density_min         -1.246
_refine_diff_density_rms         0.181
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.00(3)
_refine_ls_extinction_coef       0.029(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   0.974
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     194
_refine_ls_number_reflns         2796
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.974
_refine_ls_R_factor_all          0.1101
_refine_ls_R_factor_gt           0.0946
_refine_ls_shift/su_max          0.026
_refine_ls_shift/su_mean         0.003
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1656P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2239
_refine_ls_wR_factor_ref         0.2343
_reflns_number_gt                1996
_reflns_number_total             2796
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo801135j_si_001.cif
_cod_data_source_block           cd27217
_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_enum 1527 2010-12-29 10:47:43Z saulius 
;
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               4023653