A new approach to enantiopure inherently chiral calix[4]arenes: determination of their absolute configurations.
Xu, Zhen-Xiang; Zhang, Chun; Zheng, Qi-Yu; Chen, Chuan-Feng; Huang, Zhi-Tang; Organic letters 9 (2007) 4447–4450; doi:10.1021/ol701714q

data_1505539
_publ_section_title
;
 A new approach to enantiopure inherently chiral calix[4]arenes:
 determination of their absolute configurations.
;
_journal_issue                   22
_journal_name_full               'Organic letters'
_journal_page_first              4447
_journal_page_last               4450
_journal_paper_doi               10.1021/ol701714q
_journal_volume                  9
_journal_year                    2007
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C52 H72 Br N O4'
_chemical_formula_sum            'C52 H72 Br N O4'
_chemical_formula_weight         855.02
_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                 99.468(6)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.568(7)
_cell_length_b                   16.286(9)
_cell_length_c                   24.219(14)
_cell_measurement_reflns_used    7821
_cell_measurement_temperature    113(2)
_cell_measurement_theta_max      26.2
_cell_measurement_theta_min      1.5
_cell_volume                     4890(5)
_computing_cell_refinement       CrystalClear
_computing_data_collection       CrystalClear
_computing_data_reduction        CrystalClear
_computing_publication_material  'CrystalStructure 3.7.0'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      113(2)
_diffrn_detector_area_resol_mean 7.31
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Rigaku Saturn'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  confocal
_diffrn_radiation_source         'rotating anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71070
_diffrn_reflns_av_R_equivalents  0.0769
_diffrn_reflns_av_sigmaI/netI    0.1154
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -28
_diffrn_reflns_number            37163
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.51
_exptl_absorpt_coefficient_mu    0.883
_exptl_absorpt_correction_T_max  0.9169
_exptl_absorpt_correction_T_min  0.7901
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Jacobson, R. (1998) Private communication'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.161
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       platelet
_exptl_crystal_F_000             1832
_exptl_crystal_size_max          0.28
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.565
_refine_diff_density_min         -0.429
_refine_diff_density_rms         0.066
_refine_ls_abs_structure_details
'Flack H D (1983), 7203 Friedel Pairs, Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.026(7)
_refine_ls_extinction_coef       0.0012(2)
_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   1.083
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     1115
_refine_ls_number_reflns         16106
_refine_ls_number_restraints     65
_refine_ls_restrained_S_all      1.088
_refine_ls_R_factor_all          0.0911
_refine_ls_R_factor_gt           0.0677
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0435P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1293
_refine_ls_wR_factor_ref         0.1411
_reflns_number_gt                12710
_reflns_number_total             16106
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol701714q-file003.cif
_cod_data_source_block           shelxl
_cod_database_code               1505539