Bis(carbene)pyridine Complexes of Cr(III): Exceptionally Active Catalysts for the Oligomerization of Ethylene
David S. McGuinness; Vernon C. Gibson; Duncan F. Wass; Jonathan W. Steed; Journal of the American Chemical Society 125 (2003) 12716–12717; doi:10.1021/ja037217o

data_4114289
_publ_section_title
;
 Bis(carbene)pyridine Complexes of Cr(III): Exceptionally Active Catalysts
 for the Oligomerization of Ethylene
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              12716
_journal_page_last               12717
_journal_paper_doi               10.1021/ja037217o
_journal_volume                  125
_journal_year                    2003
_chemical_formula_sum            'C18 H23 Cl5 Cr N5'
_chemical_formula_weight         538.66
_chemical_name_common            dmcrcnc
_chemical_name_systematic
;
 ?
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_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                 94.7420(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.6464(4)
_cell_length_b                   12.0047(4)
_cell_length_c                   15.3782(6)
_cell_measurement_temperature    120(2)
_cell_volume                     2326.67(14)
_computing_cell_refinement       'DENZO-SMN (Otwinowski & Minor, 1997)'
_computing_data_collection       'Collect (Hooft, 1999)'
_computing_data_reduction        'DENZO-SMN (Otwinowski & Minor, 1997)'
_computing_molecular_graphics    'X-Seed (Barbour, 1999)'
_computing_publication_material  'CIFTAB (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      120(2)
_diffrn_measured_fraction_theta_full 0.915
_diffrn_measured_fraction_theta_max 0.915
_diffrn_measurement_device_type  'Nonius KappaCCD'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0682
_diffrn_reflns_av_sigmaI/netI    0.1116
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            6440
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         2.15
_diffrn_standards_decay_%        0.0
_exptl_absorpt_coefficient_mu    1.081
_exptl_absorpt_correction_T_max  0.8996
_exptl_absorpt_correction_T_min  0.6716
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            yellow/green
_exptl_crystal_density_diffrn    1.538
_exptl_crystal_description       plate
_exptl_crystal_F_000             1100
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.10
_refine_diff_density_max         1.195
_refine_diff_density_min         -0.777
_refine_diff_density_rms         0.168
_refine_ls_extinction_coef       0.0032(10)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.025
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     264
_refine_ls_number_reflns         3749
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.025
_refine_ls_R_factor_all          0.1282
_refine_ls_R_factor_gt           0.0632
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0897P)^2^+2.3823P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1506
_refine_ls_wR_factor_ref         0.1795
_reflns_number_gt                2271
_reflns_number_total             3749
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja037217osi20030715_040807.cif
_cod_data_source_block           C:\structs\v_gibson\dmcrcnc\DMCRCNC.CIF
_cod_database_code               4114289