Mechanism of the Ti(III)-Catalyzed Acyloin-Type Umpolung: A Catalyst-Controlled Radical Reaction.
Streuff, Jan; Feurer, Markus; Frey, Georg; Steffani, Alberto; Kacprzak, Sylwia; Weweler, Jens; Leijendekker, Leonardus H.; Kratzert, Daniel; Plattner, Dietmar A.; Journal of the American Chemical Society 137 (2015) 14396–14405; doi:10.1021/jacs.5b09223

data_4129657
_publ_section_title
;
 Mechanism of the Ti(III)-Catalyzed Acyloin-Type Umpolung: A
 Catalyst-Controlled Radical Reaction.
;
_journal_issue                   45
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              14396
_journal_page_last               14405
_journal_paper_doi               10.1021/jacs.5b09223
_journal_volume                  137
_journal_year                    2015
_chemical_formula_sum            'C36 H34 Cl2 N2 Ti2'
_chemical_formula_weight         661.35
_space_group_crystal_system      orthorhombic
_space_group_IT_number           18
_space_group_name_Hall           'P 2 2ab'
_space_group_name_H-M_alt        'P 21 21 2'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   23.8731(7)
_cell_length_b                   7.6684(17)
_cell_length_c                   8.113(8)
_cell_measurement_reflns_used    4554
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      52.664
_cell_measurement_theta_min      5.303
_cell_volume                     1485.2(15)
_computing_cell_refinement       'SAINT V8.34A'
_computing_data_collection       'APEX2 v2013.10'
_computing_data_reduction        'SAINT V8.34A'
_computing_structure_refinement  'SHELXL-2014 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXT-2014 (Sheldrick, 2014)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.990
_diffrn_measured_fraction_theta_max 0.982
_diffrn_measurement_device_type  'Bruker Smart Apex II Quazar'
_diffrn_measurement_method       'omega scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_unetI/netI     0.0713
_diffrn_reflns_Laue_measured_fraction_full 0.990
_diffrn_reflns_Laue_measured_fraction_max 0.982
_diffrn_reflns_limit_h_max       29
_diffrn_reflns_limit_h_min       -29
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            19876
_diffrn_reflns_point_group_measured_fraction_full 0.993
_diffrn_reflns_point_group_measured_fraction_max 0.985
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         26.527
_diffrn_reflns_theta_min         2.652
_diffrn_source                   'INCOATEC Mo Microsource'
_exptl_absorpt_coefficient_mu    0.747
_exptl_absorpt_correction_T_max  0.745372
_exptl_absorpt_correction_T_min  0.630687
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'TWINABS - Version 2012/1'
_exptl_crystal_density_diffrn    1.479
_exptl_crystal_F_000             684
_exptl_crystal_size_max          0.150
_exptl_crystal_size_mid          0.110
_exptl_crystal_size_min          0.090
_refine_diff_density_max         0.367
_refine_diff_density_min         -0.302
_refine_diff_density_rms         0.058
_refine_ls_abs_structure_details
;
 Flack x determined using 1104 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.034(13)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.019
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     191
_refine_ls_number_reflns         19876
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.019
_refine_ls_R_factor_all          0.0544
_refine_ls_R_factor_gt           0.0417
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0206P)^2^+1.1624P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0891
_refine_ls_wR_factor_ref         0.0939
_reflns_Friedel_coverage         0.715
_reflns_Friedel_fraction_full    0.998
_reflns_Friedel_fraction_max     0.990
_reflns_number_gt                17372
_reflns_number_total             19876
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja5b09223_si_004.cif
_cod_data_source_block           twin5
_cod_database_code               4129657
_shelx_estimated_absorpt_t_min   0.896
_shelx_estimated_absorpt_t_max   0.936
_shelxl_version_number           2014-3
_shelx_res_checksum              41507
_shelx_hkl_checksum              13673