Enantioselective Synthesis of Cyclobutenes by Intermolecular [2+2] Cycloaddition with Non-C2 Symmetric Digold Catalysts.
García-Morales, Cristina; Ranieri, Beatrice; Escofet, Imma; López-Suarez, Laura; Obradors, Carla; Konovalov, Andrey I.; Echavarren, Antonio M.; Journal of the American Chemical Society  (2017) –; doi:10.1021/jacs.7b07651

data_4126450
_publ_section_title
;
 Enantioselective Synthesis of Cyclobutenes by Intermolecular [2+2]
 Cycloaddition with Non-C2 Symmetric Digold Catalysts.
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_paper_doi               10.1021/jacs.7b07651
_journal_year                    2017
_chemical_formula_sum            'C28 H24 F2'
_chemical_formula_weight         398.47
_space_group_IT_number           15
_space_group_name_Hall           '-C 2yc'
_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
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                90
_cell_angle_beta                 101.5997(19)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   23.1418(14)
_cell_length_b                   5.7036(3)
_cell_length_c                   15.8393(10)
_cell_measurement_reflns_used    3288
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      28.04
_cell_measurement_theta_min      2.63
_cell_volume                     2048.0(2)
_computing_cell_refinement       'Bruker APEX2 v2014.9-0'
_computing_data_collection       'Bruker APEX2 v2014.9-0'
_computing_data_reduction        'Bruker SAINT V7.60A'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2014 (Sheldrick, 2014)'
_computing_structure_solution    Sir2011
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 512
_diffrn_detector_type            '4K CCD area detector APEX II'
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'APEX DUO Kappa 4-axis goniometer'
_diffrn_measurement_method
;
 Fullsphere data collection, phi and omega scans
;
_diffrn_measurement_specimen_support 'magnetic support with MicroMount'
_diffrn_radiation_monochromator  'Quazar MX Multilayer Optics'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 0.997
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 0.997
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         29.653
_diffrn_reflns_theta_min         1.797
_diffrn_source                   'Microfocus source E025 IuS'
_diffrn_source_current           0.6
_diffrn_source_power             50
_diffrn_source_size              '0.2 mm x 0.2 mm fine focus'
_diffrn_source_type              'Bruker APEX DUO'
_exptl_absorpt_coefficient_mu    0.086
_exptl_absorpt_correction_T_max  0.999
_exptl_absorpt_correction_T_min  0.915
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
; 
 SADABS Version 2008/1 Bruker-Nonius
 Blessing, Acta Cryst. (1995) A51 33-38
;
_exptl_crystal_density_diffrn    1.292
_exptl_crystal_description       Plate
_exptl_crystal_F_000             840
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.01
_refine_diff_density_max         0.421
_refine_diff_density_min         -0.351
_refine_diff_density_rms         0.068
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.159
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     137
_refine_ls_number_reflns         2882
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.159
_refine_ls_R_factor_all          0.0920
_refine_ls_R_factor_gt           0.0710
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0238P)^2^+8.0798P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1474
_refine_ls_wR_factor_ref         0.1551
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2223
_reflns_number_total             2882
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja7b07651_si_008.cif
_cod_data_source_block           mo_CG30531_0m
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to
/home/data/users/saulius/crontab/automatic-downloads/rss-feeds/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

'_exptl_absorpt_correction_type' value 'Multi-scan' changed to
'multi-scan' according to
/home/data/users/saulius/crontab/automatic-downloads/rss-feeds/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 4973 2017-02-22 13:04:09Z antanas 
;
_cod_original_sg_symbol_H-M      C2/c
_cod_database_code               4126450
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.987
_shelx_estimated_absorpt_t_max   0.999
_shelx_res_checksum              20941
_shelx_hkl_checksum              20836