Catalytic enantioselective synthesis of perfluoroalkyl-substituted β-lactones via a concerted asynchronous [2+2] cycloaddition: A synthetic and computational study
Barrios Antunez, Diego; Greenhalgh, Mark; Brueckner, Alexander C.; Walden, Daniel M.; Elías-Rodríguez, Pilar; Roberts, Patrick; Young, Benjamin; West, Thomas; Slawin, Alexandra; Ha Yeon Cheong, Paul; Smith, Andrew D.; Chemical Science  (2019) –; doi:10.1039/C9SC00390H

data_1550958
_publ_section_title
;
 Catalytic enantioselective synthesis of perfluoroalkyl-substituted
 \b-lactones via a concerted asynchronous [2+2] cycloaddition: A synthetic
 and computational study
;
_journal_name_full               'Chemical Science'
_journal_paper_doi               10.1039/C9SC00390H
_journal_year                    2019
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C19 H15 Br F5 N O2'
_chemical_formula_sum            'C19 H15 Br F5 N O2'
_chemical_formula_weight         464.23
_space_group_crystal_system      monoclinic
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_date             2016-08-03
_audit_creation_method           'by CrystalStructure 4.2'
_audit_update_record
;
2018-12-19 deposited with the CCDC.    2019-04-29 downloaded from the CCDC.
;
_cell_angle_alpha                90.0000
_cell_angle_beta                 101.939(9)
_cell_angle_gamma                90.0000
_cell_formula_units_Z            2
_cell_length_a                   11.753(6)
_cell_length_b                   6.281(3)
_cell_length_c                   13.273(6)
_cell_measurement_reflns_used    3090
_cell_measurement_temperature    93
_cell_measurement_theta_max      27.40
_cell_measurement_theta_min      1.80
_cell_volume                     958.6(8)
_computing_cell_refinement       'CrystalClear-SM Expert 2.1 b45'
_computing_data_collection       'CrystalClear-SM Expert 2.1 b45 (Rigaku, 2015)'
_computing_data_reduction        'CrystalClear-SM Expert 2.1 b45'
_computing_molecular_graphics    'CrystalStructure 4.2'
_computing_publication_material  'CrystalStructure 4.2 (Rigaku, 2015)'
_computing_structure_refinement  'SHELXL Version 2014/7 (Sheldrick, 2008)'
_computing_structure_solution    'SIR2011 (Burla, et al., 2012)'
_diffrn_ambient_temperature      93
_diffrn_detector_area_resol_mean 5.814
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Rigaku XtaLAB P200'
_diffrn_measurement_method       \w
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71075
_diffrn_reflns_av_R_equivalents  0.0639
_diffrn_reflns_Laue_measured_fraction_full 0.998
_diffrn_reflns_Laue_measured_fraction_max 0.996
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            10431
_diffrn_reflns_point_group_measured_fraction_full 0.988
_diffrn_reflns_point_group_measured_fraction_max 0.985
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.319
_diffrn_reflns_theta_min         1.771
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    2.211
_exptl_absorpt_correction_T_max  0.936
_exptl_absorpt_correction_T_min  0.442
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'REQAB (Rigaku, 1998)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.608
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             464.00
_exptl_crystal_size_max          0.100
_exptl_crystal_size_mid          0.100
_exptl_crystal_size_min          0.030
_refine_diff_density_max         0.39
_refine_diff_density_min         -0.32
_refine_ls_abs_structure_details
;
 Flack x determined using 1082 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   -0.016(9)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.697
_refine_ls_hydrogen_treatment    constr
_refine_ls_number_parameters     253
_refine_ls_number_reflns         3443
_refine_ls_number_restraints     1
_refine_ls_R_factor_all          0.0376
_refine_ls_R_factor_gt           0.0343
_refine_ls_shift/su_max          0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details     'w = 1/[\s^2^(Fo^2^)]'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0617
_refine_ls_wR_factor_ref         0.0626
_reflns_Friedel_coverage         0.800
_reflns_Friedel_fraction_full    0.976
_reflns_Friedel_fraction_max     0.972
_reflns_number_gt                2979
_reflns_number_total             3443
_reflns_threshold_expression     F^2^>2.0\s(F^2^)
_cod_data_source_file            c9sc00390h2.cif
_cod_data_source_block           47
_cod_database_code               1550958
_shelx_res_checksum              10650