Enantioselective Synthesis of Highly Substituted Chromans via the Oxa-Michael-Michael Cascade Reaction with a Bifunctional Organocatalyst.
Saha, Prasenjit; Biswas, Arnab; Molleti, Nagaraju; Singh, Vinod K.; The Journal of organic chemistry 80 (2015) 11115–11122; doi:10.1021/acs.joc.5b01751

data_4036367
_publ_section_title
;
 Enantioselective Synthesis of Highly Substituted Chromans via the
 Oxa-Michael-Michael Cascade Reaction with a Bifunctional Organocatalyst.
;
_journal_issue                   21
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              11115
_journal_page_last               11122
_journal_paper_doi               10.1021/acs.joc.5b01751
_journal_volume                  80
_journal_year                    2015
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C23 H18 Cl N O4'
_chemical_formula_sum            'C23 H18 Cl N O4'
_chemical_formula_weight         407.83
_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'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014/6
_cell_angle_alpha                90
_cell_angle_beta                 92.466(5)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   8.1242(10)
_cell_length_b                   5.5478(7)
_cell_length_c                   21.829(3)
_cell_measurement_temperature    296(2)
_cell_volume                     983.0(2)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_structure_refinement  'SHELXL-2014/6 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0676
_diffrn_reflns_av_unetI/netI     0.0473
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            22111
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         26.372
_diffrn_reflns_theta_min         2.509
_diffrn_source                   'fine focus sealed tube'
_exptl_absorpt_coefficient_mu    0.224
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.378
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             424
_exptl_crystal_size_max          0.23
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.182
_refine_diff_density_min         -0.158
_refine_diff_density_rms         0.037
_refine_ls_abs_structure_details
;
 Flack x determined using 1162 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.04(4)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.842
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     262
_refine_ls_number_reflns         4004
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.842
_refine_ls_R_factor_all          0.0618
_refine_ls_R_factor_gt           0.0395
_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^)+(0.1000P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1056
_refine_ls_wR_factor_ref         0.1219
_reflns_Friedel_coverage         0.804
_reflns_Friedel_fraction_full    0.999
_reflns_Friedel_fraction_max     0.999
_reflns_number_gt                3112
_reflns_number_total             4004
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            jo5b01751_si_002.cif
_cod_data_source_block           S8_a
_cod_original_cell_volume        982.9(2)
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               4036367
_shelxl_version_number           2014/6
_shelx_res_checksum              39735
_shelx_hkl_checksum              12779