Directing Group Assisted Nucleophilic Substitution of Propargylic Alcohols via o-Quinone Methide Intermediates: Brønsted Acid Catalyzed, Highly Enantio- and Diastereoselective Synthesis of 7-Alkynyl-12a-acetamido-Substituted Benzoxanthenes.
Saha, Satyajit; Schneider, Christoph; Organic letters 17 (2015) 648–651; doi:10.1021/ol503662g

data_1518772
_publ_section_title
;
 Directing Group Assisted Nucleophilic Substitution of Propargylic
 Alcohols via o-Quinone Methide Intermediates: Br\/onsted Acid Catalyzed,
 Highly Enantio- and Diastereoselective Synthesis of
 7-Alkynyl-12a-acetamido-Substituted Benzoxanthenes.
;
_journal_issue                   3
_journal_name_full               'Organic letters'
_journal_page_first              648
_journal_page_last               651
_journal_paper_doi               10.1021/ol503662g
_journal_volume                  17
_journal_year                    2015
_chemical_absolute_configuration rmad
_chemical_formula_sum            'C28 H23 Br Cl3 N O2'
_chemical_formula_weight         591.73
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_Int_Tables_number      19
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_date             2014-12-10T10:13:51-00:00
_audit_creation_method           'WinGX routine CIF_UPDATE'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   9.6557(2)
_cell_length_b                   10.7366(3)
_cell_length_c                   25.0366(4)
_cell_measurement_reflns_used    7269
_cell_measurement_temperature    130(2)
_cell_measurement_theta_max      28.387
_cell_measurement_theta_min      2.936
_cell_volume                     2595.53(10)
_computing_cell_refinement
;
        CrysAlisPro, Agilent Technologies,
        Version 1.171.37.34a (release 02-06-2014 CrysAlis171 .NET)
        (compiled Jun  2 2014,16:24:16)
;
_computing_data_collection
;
        CrysAlisPro, Agilent Technologies,
        Version 1.171.37.34a (release 02-06-2014 CrysAlis171 .NET)
        (compiled Jun  2 2014,16:24:16)
;
_computing_data_reduction
;
        CrysAlisPro, Agilent Technologies,
        Version 1.171.37.34a (release 02-06-2014 CrysAlis171 .NET)
        (compiled Jun  2 2014,16:24:16)
;
_computing_molecular_graphics
;
 ORTEP3 for Windows
 L. J. Farrugia, J. Appl. Crystallogr. 1997, 30, 565.
;
_computing_publication_material
;
 WINGX
 L.J. Farrugia,
 J. Appl. Cryst., 2012, 45, 849-854.
;
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution
;
 SHELXS-2013
 Program for Crystal Structure Analysis (Release 2013-1)
 G. M. Sheldrick, Instit\"ut f\"ur Anorganische Chemie der Universit\"at,
 Tammanstrasse 4, D-3400 G\"ottingen, Germany.
 G. M. Sheldrick, Acta. Cryst., 2008, A64, 112 - 122
;
_diffrn_ambient_temperature      130(2)
_diffrn_detector                 'CCD plate'
_diffrn_detector_area_resol_mean 16.356
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'Xcalibur, Sapphire3, Gemini'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_UB_11      0.0117746
_diffrn_orient_matrix_UB_12      0.0043845
_diffrn_orient_matrix_UB_13      -0.0279035
_diffrn_orient_matrix_UB_21      -0.0062497
_diffrn_orient_matrix_UB_22      0.0657494
_diffrn_orient_matrix_UB_23      0.001495
_diffrn_orient_matrix_UB_31      0.0722031
_diffrn_orient_matrix_UB_32      0.0050435
_diffrn_orient_matrix_UB_33      0.0046877
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0347
_diffrn_reflns_av_unetI/netI     0.0482
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       33
_diffrn_reflns_limit_l_min       -33
_diffrn_reflns_number            26327
_diffrn_reflns_point_group_measured_fraction_full 1
_diffrn_reflns_point_group_measured_fraction_max 1
_diffrn_reflns_theta_full        28.28
_diffrn_reflns_theta_max         28.28
_diffrn_reflns_theta_min         2.499
_diffrn_source                   'Enhance (Mo) X-ray Source'
_exptl_absorpt_coefficient_mu    1.919
_exptl_absorpt_correction_T_max  1
_exptl_absorpt_correction_T_min  0.95068
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
        CrysAlisPro, Agilent Technologies,
        Version 1.171.37.34a (release 02-06-2014 CrysAlis171 .NET)
        (compiled Jun  2 2014,16:24:16)
        Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
        Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            'clear colourless'
_exptl_crystal_density_diffrn    1.514
_exptl_crystal_description       prism
_exptl_crystal_F_000             1200
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.15
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.314
_refine_diff_density_min         -0.548
_refine_diff_density_rms         0.05
_refine_ls_abs_structure_details
;
 Flack x determined using 2181 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   -0.008(3)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.024
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     424
_refine_ls_number_reflns         6438
_refine_ls_number_restraints     6
_refine_ls_restrained_S_all      1.024
_refine_ls_R_factor_all          0.0425
_refine_ls_R_factor_gt           0.034
_refine_ls_shift/su_max          0
_refine_ls_shift/su_mean         0
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0185P)^2^+1.5259P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0628
_refine_ls_wR_factor_ref         0.0662
_reflns_number_gt                5724
_reflns_number_total             6438
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ccdc_deposit.cif
_cod_data_source_block           x2151fin
_cod_database_code               1518772