Quinone-Annulated N-Heterocyclic Carbene-Transition-Metal Complexes: Observation of π-Backbonding Using FT-IR Spectroscopy and Cyclic Voltammetry
Matthew D. Sanderson; Justin W. Kamplain; Christopher W. Bielawski; Journal of the American Chemical Society 128 (2006) 16514–16515; doi:10.1021/ja067475w

data_4111317
_publ_section_title
;
 Quinone-Annulated N-Heterocyclic Carbene-Transition-Metal Complexes:
 Observation of \p-Backbonding Using FT-IR Spectroscopy and Cyclic
 Voltammetry
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              16514
_journal_page_last               16515
_journal_paper_doi               10.1021/ja067475w
_journal_volume                  128
_journal_year                    2006
_chemical_formula_sum            'C29 H27 Cl N2 O2'
_chemical_formula_weight         470.98
_space_group_IT_number           11
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 2yb'
_symmetry_space_group_name_H-M   'P 1 21/m 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                 96.618(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   7.9224(2)
_cell_length_b                   16.4652(5)
_cell_length_c                   9.3242(2)
_cell_measurement_reflns_used    3103
_cell_measurement_temperature    153(2)
_cell_measurement_theta_max      27.5
_cell_measurement_theta_min      1
_cell_volume                     1208.18(5)
_computing_cell_refinement       'Collect software, Nonius B.V. 1998'
_computing_data_collection       'Collect software, Nonius B.V. 1998'
_computing_data_reduction
;
DENZO and Scalepack (Otwinoski and Minor, 1997)
;
_computing_molecular_graphics    'XP SHELXTL/PC, Siemens Analytical'
_computing_structure_refinement  'XL SHELXTL/PC, Siemens Analytical'
_computing_structure_solution
;

SIR97 - Altomare A., Burla M.C., Camalli M., Cascarano G.L., Giacovazzo C., 
Guagliardi A., Moliterni A.G.G., Polidori G.,Spagna R.
;
_diffrn_ambient_temperature      153(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Nonius Kappa CCD'
_diffrn_measurement_method       '\f and \w scans'
_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  0.0297
_diffrn_reflns_av_sigmaI/netI    0.0424
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            4947
_diffrn_reflns_theta_full        27.50
_diffrn_reflns_theta_max         27.50
_diffrn_reflns_theta_min         3.20
_exptl_absorpt_coefficient_mu    0.187
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.295
_exptl_crystal_description       prisms
_exptl_crystal_F_000             496
_exptl_crystal_size_max          0.17
_exptl_crystal_size_mid          0.14
_exptl_crystal_size_min          0.12
_refine_diff_density_max         0.223
_refine_diff_density_min         -0.193
_refine_diff_density_rms         0.041
_refine_ls_extinction_coef       0.006(2)
_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   1.040
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     213
_refine_ls_number_reflns         2855
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.040
_refine_ls_R_factor_all          0.0659
_refine_ls_R_factor_gt           0.0463
_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^)+(0.0427P)^2^+0.5369P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1042
_refine_ls_wR_factor_ref         0.1124
_reflns_number_gt                2227
_reflns_number_total             2855
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja067475wsi20061023_034039_1.cif
_cod_data_source_block           ms622
_cod_original_sg_symbol_H-M      'P -1'
_cod_database_code               4111317