[2.2]paracyclophane/dehydroannulene hybrids: probing the aromaticity of the dehydro[14]annulene framework.
Hinrichs, Heino; Fischer, Axel K.; Jones, Peter G.; Hopf, Henning; Haley, Michael M.; Organic letters 7 (2005) 3793–3795; doi:10.1021/ol0514552

data_1506671
_publ_section_title
;
 [2.2]paracyclophane/dehydroannulene hybrids: probing the aromaticity of
 the dehydro[14]annulene framework.
;
_journal_issue                   17
_journal_name_full               'Organic letters'
_journal_page_first              3793
_journal_page_last               3795
_journal_paper_doi               10.1021/ol0514552
_journal_volume                  7
_journal_year                    2005
_chemical_formula_sum            'C42 H40 Si2'
_chemical_formula_weight         600.92
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_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   9.3588(8)
_cell_length_b                   12.8978(12)
_cell_length_c                   28.840(3)
_cell_measurement_reflns_used    6072
_cell_measurement_temperature    133(2)
_cell_measurement_theta_max      28
_cell_measurement_theta_min      2.3
_cell_volume                     3481.2(6)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Siemens XP'
_computing_publication_material  SHELXL-97
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      133(2)
_diffrn_detector_area_resol_mean 8.192
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker SMART 1000 CCD'
_diffrn_measurement_method       \w-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  0.0250
_diffrn_reflns_av_sigmaI/netI    0.0294
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       38
_diffrn_reflns_limit_l_min       -35
_diffrn_reflns_number            24660
_diffrn_reflns_theta_full        28.00
_diffrn_reflns_theta_max         28.02
_diffrn_reflns_theta_min         1.41
_exptl_absorpt_coefficient_mu    0.130
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.147
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1280
_exptl_crystal_size_max          0.55
_exptl_crystal_size_mid          0.55
_exptl_crystal_size_min          0.50
_refine_diff_density_max         0.330
_refine_diff_density_min         -0.165
_refine_diff_density_rms         0.038
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.21(7)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.017
_refine_ls_hydrogen_treatment    'rigid methyls, others riding'
_refine_ls_matrix_type           full
_refine_ls_number_parameters     404
_refine_ls_number_reflns         8401
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.017
_refine_ls_R_factor_all          0.0381
_refine_ls_R_factor_gt           0.0326
_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^)+(0.0542P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0822
_refine_ls_wR_factor_ref         0.0845
_reflns_number_gt                7542
_reflns_number_total             8401
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol0514552si20050622_015228.cif
_cod_data_source_block           heihi
_cod_original_cell_volume        3481.2(5)
_cod_database_code               1506671