Stereospecific Asymmetric N-Heterocyclic Carbene (NHC)-Catalyzed Redox Synthesis of Trifluoromethyl Dihydropyranones and Mechanistic Insights
Alyn T. Davies; James E. Taylor; James Douglas; Christopher J. Collett; Louis C. Morrill; Charlene Fallan; Alexandra M. Z. Slawin; Gwydion Churchill; Andrew D. Smith; Journal of Organic Chemistry 78 (2013) 9243–9257; doi:10.1021/jo401433q

data_4028603
_publ_section_title
;
 Stereospecific Asymmetric N-Heterocyclic Carbene (NHC)-Catalyzed Redox
 Synthesis of Trifluoromethyl Dihydropyranones and Mechanistic Insights
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              9243
_journal_page_last               9257
_journal_paper_doi               10.1021/jo401433q
_journal_volume                  78
_journal_year                    2013
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C16 H16 Br F3 O2'
_chemical_formula_sum            'C16 H16 Br F3 O2'
_chemical_formula_weight         377.20
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      4
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.0000
_cell_angle_beta                 101.315(13)
_cell_angle_gamma                90.0000
_cell_formula_units_Z            2
_cell_length_a                   11.462(6)
_cell_length_b                   5.423(3)
_cell_length_c                   12.416(5)
_cell_measurement_reflns_used    2804
_cell_measurement_temperature    93
_cell_measurement_theta_max      25.35
_cell_measurement_theta_min      2.21
_cell_volume                     756.8(7)
_computing_cell_refinement       'CrystalClear-SM Expert 2.0 rc13'
_computing_data_collection
'CrystalClear-SM Expert 2.0 rc13 (Rigaku, 2009)'
_computing_data_reduction        'CrystalClear-SM Expert 2.0 rc13'
_computing_molecular_graphics    'CrystalStructure 4.0'
_computing_publication_material  'CrystalStructure 4.0 (Rigaku, 2010)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'DIRDIF99-PATTY (Gould, et al., 1999)'
_diffrn_ambient_temperature      93
_diffrn_detector_area_resol_mean 14.629
_diffrn_measured_fraction_theta_full 0.991
_diffrn_measured_fraction_theta_max 0.991
_diffrn_measurement_device_type  'Rigaku Mercury70'
_diffrn_measurement_method       \w
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71075
_diffrn_reflns_av_R_equivalents  0.0625
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       5
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            4765
_diffrn_reflns_theta_full        25.37
_diffrn_reflns_theta_max         25.37
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    2.760
_exptl_absorpt_correction_T_max  0.973
_exptl_absorpt_correction_T_min  0.373
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'REQAB (Rigaku, 1998)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.655
_exptl_crystal_description       prism
_exptl_crystal_F_000             380.00
_exptl_crystal_size_max          0.100
_exptl_crystal_size_mid          0.030
_exptl_crystal_size_min          0.010
_refine_diff_density_max         0.440
_refine_diff_density_min         -0.510
_refine_ls_abs_structure_details
'Flack, H. D. (1983), Acta Cryst. A39, 876-881.  872 Friedel Pairs'
_refine_ls_abs_structure_Flack   0.009(13)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.805
_refine_ls_hydrogen_treatment    constr
_refine_ls_number_parameters     199
_refine_ls_number_reflns         2406
_refine_ls_number_restraints     1
_refine_ls_R_factor_gt           0.0456
_refine_ls_shift/su_max          0.003
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0657P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         0.1091
_reflns_number_gt                2162
_reflns_number_total             2406
_reflns_threshold_expression     F^2^>2.0\s(F^2^)
_cod_data_source_file            jo401433q_si_002.cif
_cod_data_source_block           12
_cod_original_cell_volume        756.7(6)
_cod_database_code               4028603