Generation and Trapping of a Cage Annulated Vinylidenecarbene and Approaches to Its Cycloalkyne Isomer
Bichismitha Sahu; Guddeangadi N. Gururaja; Tarun Kumar; Anamitra Chatterjee; Bishwajit Ganguly; Shaikh M. Mobin; Irishi N. N. Namboothiri; Journal of Organic Chemistry 77 (2012) 6998–7004; doi:10.1021/jo301215d

data_4027403
_publ_section_title
;
 Generation and Trapping of a Cage Annulated Vinylidenecarbene and
 Approaches to Its Cycloalkyne Isomer
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              6998
_journal_page_last               7004
_journal_paper_doi               10.1021/jo301215d
_journal_volume                  77
_journal_year                    2012
_chemical_formula_sum            'C12 H8 Br4'
_chemical_formula_weight         471.82
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/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                 132.73(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   15.8820(16)
_cell_length_b                   9.5654(7)
_cell_length_c                   11.5424(12)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      13.6100
_cell_measurement_theta_min      5.5000
_cell_volume                     1288(2)
_computing_cell_refinement       'Argus (Nonius, MACH3 software)'
_computing_data_collection       'Argus (Nonius, MACH3 software)'
_computing_data_reduction        'Maxus (Nonius software)'
_computing_molecular_graphics    Ortep
_computing_publication_material  Shelx97
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Enraf-Nonius CAD-4'
_diffrn_measurement_method       \w/q-scan
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           ' MoK\a'
_diffrn_radiation_wavelength     0.70930
_diffrn_reflns_av_R_equivalents  0.0974
_diffrn_reflns_av_sigmaI/netI    0.0395
_diffrn_reflns_limit_h_max       0
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -2
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            1394
_diffrn_reflns_theta_full        24.97
_diffrn_reflns_theta_max         24.97
_diffrn_reflns_theta_min         2.75
_diffrn_standards_decay_%        <3%
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    12.465
_exptl_absorpt_correction_T_max  1.000
_exptl_absorpt_correction_T_min  0.749
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details
;
psi-scan (North, Philips & Mathews, 1968)
;
_exptl_crystal_colour            Colourless
_exptl_crystal_density_diffrn    2.433
_exptl_crystal_description       Block
_exptl_crystal_F_000             880
_exptl_crystal_size_max          0.32
_exptl_crystal_size_mid          0.28
_exptl_crystal_size_min          0.22
_refine_diff_density_max         1.702
_refine_diff_density_min         -1.401
_refine_diff_density_rms         0.340
_refine_ls_extinction_coef       0.0069(15)
_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   1.143
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     74
_refine_ls_number_reflns         1127
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.143
_refine_ls_R_factor_all          0.1072
_refine_ls_R_factor_gt           0.0770
_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^)+(0.1418P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1878
_refine_ls_wR_factor_ref         0.2069
_reflns_number_gt                843
_reflns_number_total             1127
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo301215d_si_003.cif
_cod_data_source_block           iin09a
_cod_original_cell_volume        1288.1(2)
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               4027403