Synthetic and Quantum Mechanical Studies into theN-Heterocyclic Carbene Catalyzed (4 + 2) Cycloaddition
Sarah J. Ryan; Andreas Stasch; Michael N. Paddon-Row; David W. Lupton; Journal of Organic Chemistry 77 (2012) 1113–1124; doi:10.1021/jo202500k

data_4026912
_publ_section_title
;
 Synthetic and Quantum Mechanical Studies into theN-Heterocyclic Carbene
 Catalyzed (4 + 2) Cycloaddition
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              1113
_journal_page_last               1124
_journal_paper_doi               10.1021/jo202500k
_journal_volume                  77
_journal_year                    2012
_chemical_formula_moiety         'C23 H26 O2, 0.5 (C7 H8)'
_chemical_formula_sum            'C26.5 H30 O2'
_chemical_formula_weight         380.51
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_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                 112.12(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   23.192(5)
_cell_length_b                   9.2510(19)
_cell_length_c                   21.285(4)
_cell_measurement_temperature    100(2)
_cell_volume                     4230.6(17)
_computing_cell_refinement       'XDS (Kabsch, 1993)'
_computing_data_collection       'BluIce (McPhillips, 2002)'
_computing_data_reduction        'XDS (Kabsch, 1993)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.960
_diffrn_measured_fraction_theta_max 0.928
_diffrn_measurement_device_type  'ADSC Quantum 210r'
_diffrn_measurement_method       '\f Scan'
_diffrn_radiation_monochromator  'Silicon Double Crystal'
_diffrn_radiation_source         'Australian Synchrotron'
_diffrn_radiation_type           Synchrotron
_diffrn_radiation_wavelength     0.71070
_diffrn_reflns_av_R_equivalents  0.0498
_diffrn_reflns_av_sigmaI/netI    0.0329
_diffrn_reflns_limit_h_max       28
_diffrn_reflns_limit_h_min       -30
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            44983
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         28.61
_diffrn_reflns_theta_min         1.92
_exptl_absorpt_coefficient_mu    0.073
_exptl_absorpt_correction_T_max  0.9993
_exptl_absorpt_correction_T_min  0.9978
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'XDS (Kabsch, 1993)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.195
_exptl_crystal_description       block
_exptl_crystal_F_000             1640
_exptl_crystal_size_max          0.03
_exptl_crystal_size_mid          0.02
_exptl_crystal_size_min          0.01
_refine_diff_density_max         0.365
_refine_diff_density_min         -0.308
_refine_diff_density_rms         0.051
_refine_ls_extinction_coef       0.044(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   1.029
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     532
_refine_ls_number_reflns         10082
_refine_ls_number_restraints     4
_refine_ls_restrained_S_all      1.029
_refine_ls_R_factor_all          0.0621
_refine_ls_R_factor_gt           0.0482
_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^)+(0.0675P)^2^+1.8805P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1221
_refine_ls_wR_factor_ref         0.1327
_reflns_number_gt                8164
_reflns_number_total             10082
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo202500k_si_003.cif
_cod_data_source_block           compound12a
_cod_original_cell_volume        4230.5(15)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_original_formula_sum        'C26.50 H30 O2'
_cod_database_code               4026912