Cascade reaction of β,γ-unsaturated α-ketoesters with phenols in trityl chloride/TFA system. Highly selective synthesis of 4-aryl-2H-chromenes and their applications.
Wu, Yan-Chao; Li, Hui-Jing; Liu, Li; Liu, Zhe; Wang, Dong; Chen, Yong-Jun; Organic & biomolecular chemistry 9 (2011) 2868–2877; doi:10.1039/c0ob01143f

data_7151822
_publ_section_title
;
 Cascade reaction of \b,\g-unsaturated \a-ketoesters with phenols in
 trityl chloride/TFA system. Highly selective synthesis of
 4-aryl-2H-chromenes and their applications.
;
_journal_issue                   8
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              2868
_journal_page_last               2877
_journal_paper_doi               10.1039/c0ob01143f
_journal_volume                  9
_journal_year                    2011
_chemical_formula_sum            'C28 H29 N O3'
_chemical_formula_weight         427.52
_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                   6.0368(12)
_cell_length_b                   13.398(3)
_cell_length_c                   29.789(6)
_cell_measurement_reflns_used    18931
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      27.47
_cell_measurement_theta_min      1.37
_cell_volume                     2409.4(9)
_computing_cell_refinement       'Rapid auto(Rigaku 2001)'
_computing_data_collection       'Rapid auto(Rigaku 2001)'
_computing_data_reduction        'Rapid auto(Rigaku 2001)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.987
_diffrn_measured_fraction_theta_max 0.987
_diffrn_measurement_device_type  'Rigaku Raxis Rapid IP'
_diffrn_measurement_method       oscillation
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Rotating Anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0473
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_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       38
_diffrn_reflns_limit_l_min       -36
_diffrn_reflns_number            18931
_diffrn_reflns_theta_full        27.47
_diffrn_reflns_theta_max         27.47
_diffrn_reflns_theta_min         1.37
_exptl_absorpt_coefficient_mu    0.076
_exptl_absorpt_correction_T_max  0.9943
_exptl_absorpt_correction_T_min  0.9455
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   abscor
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.179
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       platelet
_exptl_crystal_F_000             912
_exptl_crystal_size_max          0.75
_exptl_crystal_size_mid          0.28
_exptl_crystal_size_min          0.08
_refine_diff_density_max         0.314
_refine_diff_density_min         -0.323
_refine_diff_density_rms         0.122
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -1(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.010
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     289
_refine_ls_number_reflns         3133
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.010
_refine_ls_R_factor_all          0.0698
_refine_ls_R_factor_gt           0.0436
_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^)+(0.0619P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1095
_refine_ls_wR_factor_ref         0.1307
_reflns_number_gt                2054
_reflns_number_total             3133
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c0ob01143f.txt
_cod_data_source_block           6a
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1555 2011-01-17 13:19:09Z saulius 
;
_cod_original_cell_volume        2409.3(8)
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               7151822