Structure and Reactivity of Chromium(VI) Alkylidenes.
Wu, Pengcheng; Yap, Glenn P. A.; Theopold, Klaus H.; Journal of the American Chemical Society 140 (2018) 7088–7091; doi:10.1021/jacs.8b04882

data_4132559
_publ_section_title
;
 Structure and Reactivity of Chromium(VI) Alkylidenes.
;
_journal_issue                   23
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              7088
_journal_page_last               7091
_journal_paper_doi               10.1021/jacs.8b04882
_journal_volume                  140
_journal_year                    2018
_chemical_formula_sum            'C46 H59 Cr N2 P Si'
_chemical_formula_weight         751.01
_space_group_crystal_system      orthorhombic
_space_group_IT_number           29
_space_group_name_Hall           'P 2c -2ac'
_space_group_name_H-M_alt        'P c a 21'
_atom_sites_solution_hydrogens   mixed
_audit_creation_method           SHELXL-2017/1
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   17.0985(11)
_cell_length_b                   13.5512(9)
_cell_length_c                   21.4178(14)
_cell_measurement_reflns_used    9978
_cell_measurement_temperature    200(2)
_cell_measurement_theta_max      23.94
_cell_measurement_theta_min      2.38
_cell_volume                     4962.6(6)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2017/1 (Sheldrick, 2017)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      200(2)
_diffrn_detector_area_resol_mean 8.33
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Bruker AXS APEX diffractometer'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0426
_diffrn_reflns_av_unetI/netI     0.0318
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 0.995
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -22
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            71736
_diffrn_reflns_point_group_measured_fraction_full 0.989
_diffrn_reflns_point_group_measured_fraction_max 0.984
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.631
_diffrn_reflns_theta_min         1.503
_exptl_absorpt_coefficient_mu    0.315
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.6853
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'APEX3 (Bruker, 2015)'
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    1.005
_exptl_crystal_description       block
_exptl_crystal_F_000             1608
_exptl_crystal_size_max          0.557
_exptl_crystal_size_mid          0.480
_exptl_crystal_size_min          0.314
_refine_diff_density_max         0.558
_refine_diff_density_min         -0.228
_refine_diff_density_rms         0.040
_refine_ls_abs_structure_details
; 
 Flack x determined using 3725 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259). 
;
_refine_ls_abs_structure_Flack   -0.020(6)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.035
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     475
_refine_ls_number_reflns         11366
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.035
_refine_ls_R_factor_all          0.0588
_refine_ls_R_factor_gt           0.0424
_refine_ls_shift/su_max          0.004
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0638P)^2^+0.6044P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1053
_refine_ls_wR_factor_ref         0.1155
_reflns_Friedel_coverage         0.925
_reflns_Friedel_fraction_full    0.977
_reflns_Friedel_fraction_max     0.973
_reflns_number_gt                9046
_reflns_number_total             11366
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja8b04882_si_004.cif
_cod_data_source_block           kla0941a_sq
_cod_database_code               4132559
_shelx_shelxl_version_number     2017/1
_shelx_estimated_absorpt_t_min   0.844
_shelx_estimated_absorpt_t_max   0.908
_shelx_res_checksum              31376
_shelx_hkl_checksum              74733
_shelx_fab_checksum              52624