N-Heterocyclic Carbene-Catalyzed [4 + 2] Cyclization of Saturated Carboxylic Acid with o-Quinone Methides through in Situ Activation: Enantioselective Synthesis of Dihydrocoumarins.
Wang, Yuanfeng; Pan, Jian; Dong, Jingjiao; Yu, Chenxia; Li, Tuanjie; Wang, Xiang-Shan; Shen, Shide; Yao, Changsheng; The Journal of organic chemistry 82 (2017) 1790–1795; doi:10.1021/acs.joc.6b02444

data_4032151
_publ_section_title
;
 N-Heterocyclic Carbene-Catalyzed [4 + 2] Cyclization of Saturated
 Carboxylic Acid with o-Quinone Methides through in Situ Activation:
 Enantioselective Synthesis of Dihydrocoumarins.
;
_journal_issue                   3
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              1790
_journal_page_last               1795
_journal_paper_doi               10.1021/acs.joc.6b02444
_journal_volume                  82
_journal_year                    2017
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C23 H17 Br O5'
_chemical_formula_sum            'C23 H17 Br O5'
_chemical_formula_weight         453.28
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_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                   6.120(3)
_cell_length_b                   13.432(6)
_cell_length_c                   23.716(10)
_cell_measurement_reflns_used    1649
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      20.16
_cell_measurement_theta_min      2.99
_cell_volume                     1949.5(15)
_computing_cell_refinement       APEX2
_computing_data_collection       'APEX2 (Bruker, 2005)'
_computing_data_reduction        APEX2
_computing_molecular_graphics    SHELXTL
_computing_publication_material  'local programs'
_computing_structure_refinement  SHELXTL
_computing_structure_solution    'SHELXTL (Bruker, 2005)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.987
_diffrn_measured_fraction_theta_max 0.987
_diffrn_measurement_device_type  'APEX2 CCD detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0387
_diffrn_reflns_av_sigmaI/netI    0.0689
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            7933
_diffrn_reflns_theta_full        25.56
_diffrn_reflns_theta_max         25.56
_diffrn_reflns_theta_min         1.72
_exptl_absorpt_coefficient_mu    2.142
_exptl_absorpt_correction_T_max  0.7452
_exptl_absorpt_correction_T_min  0.6338
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Bruker, 2008)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.544
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             920
_exptl_crystal_size_max          0.32
_exptl_crystal_size_mid          0.23
_exptl_crystal_size_min          0.18
_refine_diff_density_max         0.199
_refine_diff_density_min         -0.375
_refine_diff_density_rms         0.048
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.020(9)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.028
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     263
_refine_ls_number_reflns         3585
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.028
_refine_ls_R_factor_all          0.0951
_refine_ls_R_factor_gt           0.0386
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0235P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0659
_refine_ls_wR_factor_ref         0.0780
_reflns_number_gt                2107
_reflns_number_total             3585
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo6b02444_si_002.cif
_cod_data_source_block           1
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/usr/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 4268 2015-11-12 08:31:59Z antanas 

 Adding full bibliography for 4032151.cif.
;
_cod_original_cell_volume        1949.6(15)
_cod_original_sg_symbol_H-M      'P2(1)2(1)2(1) '
_cod_database_code               4032151