Brook Rearrangement as Trigger for Carbene Generation: Synthesis of Stereodefined and Fully Substituted Cyclobutenes.
Zhang, Fa-Guang; Marek, Ilan; Journal of the American Chemical Society 139 (2017) 8364–8370; doi:10.1021/jacs.7b04255

data_4126356
_publ_section_title
;
 Brook Rearrangement as Trigger for Carbene Generation: Synthesis of
 Stereodefined and Fully Substituted Cyclobutenes.
;
_journal_issue                   24
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              8364
_journal_page_last               8370
_journal_paper_doi               10.1021/jacs.7b04255
_journal_volume                  139
_journal_year                    2017
_chemical_absolute_configuration unk
_chemical_formula_moiety         'C23 H25 N O4'
_chemical_formula_sum            'C23 H25 N O4'
_chemical_formula_weight         379.44
_chemical_name_common            'Marek108 (Fa-Guang)'
_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                 113.2450(14)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   14.4140(5)
_cell_length_b                   5.5220(2)
_cell_length_c                   28.1160(14)
_cell_measurement_reflns_used    3171
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      24.14
_cell_measurement_theta_min      1.42
_cell_volume                     2056.21(15)
_computing_cell_refinement       'DENZO HKL2000 (Otwinowski & Minor 1997)'
_computing_data_collection       'Collect (Nonius, 2006)'
_computing_data_reduction        'DENZO HKL2000 (Otwinowski & Minor 1997)'
_computing_molecular_graphics    'Mercury 3.7'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean 95
_diffrn_measured_fraction_theta_full 0.988
_diffrn_measured_fraction_theta_max 0.988
_diffrn_measurement_device_type  'Nonius KappaCCD'
_diffrn_measurement_method       'phi- and omega-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  0.0910
_diffrn_reflns_av_sigmaI/netI    0.0427
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       0
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -31
_diffrn_reflns_number            3007
_diffrn_reflns_theta_full        24.14
_diffrn_reflns_theta_max         24.14
_diffrn_reflns_theta_min         1.58
_diffrn_standards_decay_%        none
_diffrn_standards_interval_count none
_diffrn_standards_interval_time  none
_diffrn_standards_number         none
_exptl_absorpt_coefficient_mu    0.084
_exptl_absorpt_correction_T_max  0.9776
_exptl_absorpt_correction_T_min  0.9629
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;  
'HKL Denzo and Scalepack (Otwinowski & Minor 1997)'   
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.226
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             808
_exptl_crystal_size_max          0.33
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.405
_refine_diff_density_min         -0.357
_refine_diff_density_rms         0.088
_refine_ls_extinction_coef       0.16(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   1.151
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     256
_refine_ls_number_reflns         3007
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.151
_refine_ls_R_factor_all          0.1410
_refine_ls_R_factor_gt           0.1236
_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^)+(0.1107P)^2^+12.3009P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.3569
_refine_ls_wR_factor_ref         0.3688
_reflns_number_gt                2431
_reflns_number_total             3007
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja7b04255_si_003.cif
_cod_data_source_block           Marek108
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               4126356