Boron Tribromide-Assisted Chiral Phosphoric Acid Catalyst for a Highly Enantioselective Diels-Alder Reaction of 1,2-Dihydropyridines.
Hatano, Manabu; Goto, Yuta; Izumiseki, Atsuto; Akakura, Matsujiro; Ishihara, Kazuaki; Journal of the American Chemical Society 137 (2015) 13472–13475; doi:10.1021/jacs.5b08693

data_4129604
_publ_section_title
;
 Boron Tribromide-Assisted Chiral Phosphoric Acid Catalyst for a Highly
 Enantioselective Diels-Alder Reaction of 1,2-Dihydropyridines.
;
_journal_issue                   42
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              13472
_journal_page_last               13475
_journal_paper_doi               10.1021/jacs.5b08693
_journal_volume                  137
_journal_year                    2015
_chemical_formula_sum            'C15 H13 Br2 N O4'
_chemical_formula_weight         431.08
_chemical_name_common
;
(3R,3aS,6R,7S,7aS)-Phenyl-3,7-dibromo-2-oxohexahydro
-3,6-methanofuro[3,2-b]pyridine-4(2H)-carboxylate
;
_space_group_IT_number           18
_space_group_name_Hall           'P 2 2ab'
_space_group_name_H-M_alt        'P 21 21 2'
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_H-M   'P 21 21 2'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.8931(17)
_cell_length_b                   22.261(4)
_cell_length_c                   7.8277(14)
_cell_measurement_temperature    123(2)
_cell_volume                     1549.6(5)
_computing_cell_refinement       'Rigaku CrystalClear'
_computing_data_collection       'Rigaku CrystalClear'
_computing_data_reduction        'Rigaku CrystalClear'
_computing_molecular_graphics    'Rigaku CrystalStructure'
_computing_publication_material  'Rigaku CrystalStructure'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      123(2)
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type  'PILATUS 200K area detector'
_diffrn_measurement_method       'phi and omega scan'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71075
_diffrn_reflns_av_R_equivalents  0.0544
_diffrn_reflns_av_sigmaI/netI    0.0653
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       28
_diffrn_reflns_limit_k_min       -26
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            13053
_diffrn_reflns_theta_full        27.47
_diffrn_reflns_theta_max         27.47
_diffrn_reflns_theta_min         3.18
_diffrn_standards_decay_%        0
_exptl_absorpt_coefficient_mu    5.248
_exptl_absorpt_correction_T_max  0.3020
_exptl_absorpt_correction_T_min  0.2280
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'Rigaku CrystalClear'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.848
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             848
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.30
_refine_diff_density_max         0.791
_refine_diff_density_min         -0.843
_refine_diff_density_rms         0.089
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.007(8)
_refine_ls_extinction_coef       0.0015(3)
_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   0.910
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     200
_refine_ls_number_reflns         3535
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.910
_refine_ls_R_factor_all          0.0364
_refine_ls_R_factor_gt           0.0285
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0156P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0506
_refine_ls_wR_factor_ref         0.0520
_reflns_number_gt                2747
_reflns_number_total             3535
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja5b08693_si_003.cif
_cod_data_source_block           crystalclear
_cod_original_sg_symbol_H-M      P21212
_cod_database_code               4129604