6,6-Dicyanopentafulvenes: Electronic Structure and Regioselectivity in [2 + 2] Cycloaddition-Retroelectrocyclization Reactions
Aaron D. Finke; Oliver Dumele; Michal Zalibera; Daria Confortin; Pawel Cias; Govindasamy Jayamurugan; Jean-Paul Gisselbrecht; Corinne Boudon; W. Bernd Schweizer; Georg Gescheidt; François Diederich; Journal of the American Chemical Society 134 (2012) 18139–18146; doi:10.1021/ja309141r

data_4118862
_publ_contact_author_email       schweizer@org.chem.ethz.ch
_publ_contact_author_name        'B. Schweizer'
_publ_section_title
;
 6,6-Dicyanopentafulvenes: Electronic Structure and Regioselectivity in [2
 + 2] Cycloaddition-Retroelectrocyclization Reactions
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              18139
_journal_page_last               18146
_journal_paper_doi               10.1021/ja309141r
_journal_volume                  134
_journal_year                    2012
_chemical_formula_moiety         'C70 H104 N4 Si4'
_chemical_formula_sum            'C70 H104 N4 Si4'
_chemical_formula_weight         1113.93
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           148
_symmetry_cell_setting           rhombohedral
_symmetry_space_group_name_Hall  '-R 3'
_symmetry_space_group_name_H-M   'R -3 :H'
_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                120.00
_cell_formula_units_Z            18
_cell_length_a                   47.9783(16)
_cell_length_b                   47.9783(16)
_cell_length_c                   16.4921(7)
_cell_measurement_reflns_used    9899
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      22.28
_cell_measurement_theta_min      2.25
_cell_volume                     32877(2)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Platon, Ortep'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement
'OLEX2 (Dolomanov, 2009), SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w 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  0.0584
_diffrn_reflns_av_sigmaI/netI    0.0398
_diffrn_reflns_limit_h_max       50
_diffrn_reflns_limit_h_min       -55
_diffrn_reflns_limit_k_max       56
_diffrn_reflns_limit_k_min       -45
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            106362
_diffrn_reflns_theta_full        24.82
_diffrn_reflns_theta_max         24.82
_diffrn_reflns_theta_min         1.70
_exptl_absorpt_coefficient_mu    0.120
_exptl_absorpt_correction_T_max  0.9917
_exptl_absorpt_correction_T_min  0.9753
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    1.013
_exptl_crystal_description       rod
_exptl_crystal_F_000             10944
_exptl_crystal_size_max          0.21
_exptl_crystal_size_mid          0.16
_exptl_crystal_size_min          0.07
_refine_diff_density_max         1.639
_refine_diff_density_min         -0.550
_refine_diff_density_rms         0.120
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   2.775
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     718
_refine_ls_number_reflns         12533
_refine_ls_number_restraints     73
_refine_ls_restrained_S_all      2.797
_refine_ls_R_factor_all          0.1990
_refine_ls_R_factor_gt           0.1540
_refine_ls_shift/su_max          0.006
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.3991
_refine_ls_wR_factor_ref         0.4160
_reflns_number_gt                8376
_reflns_number_total             12533
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja309141r_si_001_3.cif
_cod_data_source_block           mo_d140312_0ma
_cod_original_sg_symbol_H-M      'R -3'
_cod_database_code               4118862