Stereodivergency of triazolium and imidazolium-derived NHCs for catalytic, enantioselective cyclopentane synthesis.
Kaeobamrung, Juthanat; Bode, Jeffrey W.; Organic letters 11 (2009) 677–680; doi:10.1021/ol802739d

data_1503763
_publ_section_title
;
 Stereodivergency of triazolium and imidazolium-derived NHCs for
 catalytic, enantioselective cyclopentane synthesis.
;
_journal_issue                   3
_journal_name_full               'Organic letters'
_journal_page_first              677
_journal_page_last               680
_journal_paper_doi               10.1021/ol802739d
_journal_volume                  11
_journal_year                    2009
_chemical_absolute_configuration ad
_chemical_formula_sum            'C21 H21 Br O3'
_chemical_formula_weight         401.29
_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                 102.088(6)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   5.996(2)
_cell_length_b                   24.823(9)
_cell_length_c                   12.835(5)
_cell_measurement_temperature    273(2)
_cell_volume                     1868.0(12)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      273(2)
_diffrn_measured_fraction_theta_full 0.961
_diffrn_measured_fraction_theta_max 0.961
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'Omega scan'
_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  0.3140
_diffrn_reflns_av_sigmaI/netI    0.9828
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       29
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            7882
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.62
_exptl_absorpt_coefficient_mu    2.217
_exptl_absorpt_correction_T_max  0.298
_exptl_absorpt_correction_T_min  0.257
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'psi scan'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.427
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             824
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.02
_refine_diff_density_max         0.290
_refine_diff_density_min         -0.270
_refine_diff_density_rms         0.064
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.10(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.604
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     265
_refine_ls_number_reflns         5020
_refine_ls_number_restraints     61
_refine_ls_restrained_S_all      0.604
_refine_ls_R_factor_all          0.3614
_refine_ls_R_factor_gt           0.0644
_refine_ls_shift/su_max          0.100
_refine_ls_shift/su_mean         0.003
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0200P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1063
_refine_ls_wR_factor_ref         0.1368
_reflns_number_gt                800
_reflns_number_total             5020
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol802739d_si_003.cif
_cod_data_source_block           bode3_27
_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 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      P2(1)
_cod_database_code               1503763