A versatile template for the formation of [2]pseudorotaxanes. 1,2-Bis(pyridinium)ethane axles and 24-crown-8 ether wheels.
Loeb, Stephen J.; Tiburcio, Jorge; Vella, Sarah J.; Wisner, James A.; Organic & biomolecular chemistry 4 (2006) 667–680; doi:10.1039/b514528g

data_7150398
_publ_section_title
;
 A versatile template for the formation of [2]pseudorotaxanes.
 1,2-Bis(pyridinium)ethane axles and 24-crown-8 ether wheels.
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_journal_issue                   4
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              667
_journal_page_last               680
_journal_paper_doi               10.1039/b514528g
_journal_volume                  4
_journal_year                    2006
_chemical_formula_sum            'C28 H46 B2 F8 N2 O8'
_chemical_formula_weight         712.29
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      14
_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                 93.572(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   17.433(5)
_cell_length_b                   20.012(5)
_cell_length_c                   19.631(5)
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      28.3
_cell_measurement_theta_min      1.5
_cell_volume                     6835(3)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SHELXTL XPREP'
_computing_molecular_graphics    'Bruker SHELXTL XP'
_computing_publication_material  'Bruker SHELXTL XCIF'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker APEX CCD'
_diffrn_measurement_method       'hemisphere 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  0.1631
_diffrn_reflns_av_sigmaI/netI    0.1574
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       20
_diffrn_reflns_limit_k_min       -20
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            42093
_diffrn_reflns_theta_full        20.82
_diffrn_reflns_theta_max         20.82
_diffrn_reflns_theta_min         2.31
_diffrn_standards_decay_%        <1
_diffrn_standards_number         '50 standard frames at start and end'
_exptl_absorpt_coefficient_mu    0.126
_exptl_absorpt_correction_T_max  1.000000
_exptl_absorpt_correction_T_min  0.791230
_exptl_absorpt_correction_type   empirical
_exptl_crystal_colour            block
_exptl_crystal_density_diffrn    1.384
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    .
_exptl_crystal_description       white
_exptl_crystal_F_000             2992
_exptl_crystal_size_max          0.28
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.14
_refine_diff_density_max         0.529
_refine_diff_density_min         -0.435
_refine_diff_density_rms         0.061
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.024
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     901
_refine_ls_number_reflns         7150
_refine_ls_number_restraints     42
_refine_ls_restrained_S_all      1.051
_refine_ls_R_factor_all          0.1374
_refine_ls_R_factor_gt           0.0684
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0031P)^2^+9.1044P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1509
_refine_ls_wR_factor_ref         0.1851
_reflns_number_gt                4120
_reflns_number_total             7150
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b514528g.txt
_cod_data_source_block
'[2]pseudorotaxane[(1,2-bis(pyridinium)ethane)-24C8][BF4]2'
_cod_original_cell_volume        6836(3)
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               7150398