Brønsted Acid-Catalyzed, Diastereo- and Enantioselective, Intramolecular Oxa-Diels-Alder Reaction of ortho-Quinone Methides and Unactivated Dienophiles.
Ukis, Rostyslav; Schneider, Christoph; The Journal of organic chemistry 84 (2019) 7175–7188; doi:10.1021/acs.joc.9b00860

data_4034579
_publ_section_title
;
 Br\/onsted Acid-Catalyzed, Diastereo- and Enantioselective,
 Intramolecular Oxa-Diels-Alder Reaction of ortho-Quinone Methides and
 Unactivated Dienophiles.
;
_journal_issue                   11
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              7175
_journal_page_last               7188
_journal_paper_doi               10.1021/acs.joc.9b00860
_journal_volume                  84
_journal_year                    2019
_chemical_formula_sum            'C22 H18 O2'
_chemical_formula_weight         314.36
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                90
_cell_angle_beta                 94.144(5)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   11.9718(7)
_cell_length_b                   10.0001(5)
_cell_length_c                   13.1550(7)
_cell_measurement_reflns_used    12761
_cell_measurement_temperature    180(2)
_cell_measurement_theta_max      60.9
_cell_measurement_theta_min      5.2
_cell_volume                     1570.79(15)
_computing_cell_refinement       'STOE X-AREA'
_computing_data_collection       'STOE X-AREA'
_computing_data_reduction        'STOE X-AREA'
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    SHELXS
_diffrn_ambient_temperature      180(2)
_diffrn_measured_fraction_theta_full 0.986
_diffrn_measured_fraction_theta_max 0.986
_diffrn_measurement_device_type  'STOE STADIVARI'
_diffrn_measurement_method       'rotation method, \w scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54186
_diffrn_reflns_av_R_equivalents  0.0230
_diffrn_reflns_av_unetI/netI     0.0167
_diffrn_reflns_Laue_measured_fraction_full 0.986
_diffrn_reflns_Laue_measured_fraction_max 0.986
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            12153
_diffrn_reflns_point_group_measured_fraction_full 0.986
_diffrn_reflns_point_group_measured_fraction_max 0.986
_diffrn_reflns_theta_full        60.783
_diffrn_reflns_theta_max         60.783
_diffrn_reflns_theta_min         5.562
_diffrn_source                   'GeniX 3D HF Cu'
_exptl_absorpt_coefficient_mu    0.661
_exptl_absorpt_correction_T_max  0.9701
_exptl_absorpt_correction_T_min  0.4869
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
STOE LANA, absorption correction by scaling of reflection intensities.
J. Koziskova, F. Hahn, J. Richter, J. Kozisek, "Comparison of different
absorption corrections on the model structure of tetrakis(\m~2~-acetato)-
diaqua-di-copper(II)", Acta Chimica Slovaca, vol. 9, no. 2, 2016, pp. 136 - 140.
Afterwards a spherical absorption correction was performed within STOE LANA.
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.329
_exptl_crystal_description       plate
_exptl_crystal_F_000             664
_exptl_crystal_size_max          0.240
_exptl_crystal_size_mid          0.160
_exptl_crystal_size_min          0.040
_refine_diff_density_max         0.182
_refine_diff_density_min         -0.157
_refine_diff_density_rms         0.028
_refine_ls_extinction_coef       0.0010(2)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2014/7 (Sheldrick 2014'
_refine_ls_goodness_of_fit_ref   1.070
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     218
_refine_ls_number_reflns         2359
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.070
_refine_ls_R_factor_all          0.0363
_refine_ls_R_factor_gt           0.0298
_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^)+(0.0484P)^2^+0.1958P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0806
_refine_ls_wR_factor_ref         0.0830
_reflns_Friedel_coverage         0.000
_reflns_number_gt                1985
_reflns_number_total             2359
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            jo9b00860_si_004.cif
_cod_data_source_block           sv0118trans
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               4034579
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.857
_shelx_estimated_absorpt_t_max   0.974
_shelx_res_checksum              32246
_shelx_hkl_checksum              62310