High-Oxidation-State Neutral and Cationic Tantalum(IV) Alkyl Complexes That Are Stable toward β-Hydrogen and β-Methyl Eliminations
Albert Epshteyn; Peter Y. Zavalij; Lawrence R. Sita; Journal of the American Chemical Society 128 (2006) 16052–16053; doi:10.1021/ja067011y

data_4111239
_publ_section_title
;
 High-Oxidation-State Neutral and Cationic Tantalum(IV) Alkyl Complexes
 That Are Stable toward \b-Hydrogen and \b-Methyl Eliminations
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              16052
_journal_page_last               16053
_journal_paper_doi               10.1021/ja067011y
_journal_volume                  128
_journal_year                    2006
_chemical_formula_moiety         'C26 H50 N2 Ta'
_chemical_formula_sum            'C26 H50 N2 Ta'
_chemical_formula_weight         571.63
_chemical_name_common            'Ta di-butyl complex'
_chemical_name_systematic
;
Ta di-butyl complex
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           'SHELXL-97 & ZCIF'
_cell_angle_alpha                87.2690(10)
_cell_angle_beta                 88.7370(10)
_cell_angle_gamma                68.3400(10)
_cell_formula_units_Z            2
_cell_length_a                   8.5903(4)
_cell_length_b                   9.6055(4)
_cell_length_c                   17.5663(7)
_cell_measurement_reflns_used    7303
_cell_measurement_temperature    220(2)
_cell_measurement_theta_max      29.6
_cell_measurement_theta_min      2.3
_cell_volume                     1345.58(10)
_computing_cell_refinement       'SAINT (Bruker, 1999)'
_computing_data_collection       'SMART (Bruker, 1999)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    'XSHEL (Bruker, 1999)'
_computing_publication_material  SHELXL-97
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      220(2)
_diffrn_detector                 'CCD area detector'
_diffrn_detector_area_resol_mean 8.33
_diffrn_detector_type            'Bruker Smart1000'
_diffrn_measured_fraction_theta_full 0.991
_diffrn_measured_fraction_theta_max 0.991
_diffrn_measurement_details      606,606,606,50,660
_diffrn_measurement_device_type  'three-circle diffractometer'
_diffrn_measurement_method       '\w and \f scans'
_diffrn_measurement_specimen_support 'cactus needle'
_diffrn_orient_matrix_type       standard
_diffrn_orient_matrix_UB_11      0.0054112
_diffrn_orient_matrix_UB_12      -0.0340794
_diffrn_orient_matrix_UB_13      0.0548992
_diffrn_orient_matrix_UB_21      -0.1182724
_diffrn_orient_matrix_UB_22      0.0053250
_diffrn_orient_matrix_UB_23      -0.0024227
_diffrn_orient_matrix_UB_31      0.0408848
_diffrn_orient_matrix_UB_32      -0.1066797
_diffrn_orient_matrix_UB_33      -0.0151115
_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  0.0225
_diffrn_reflns_av_sigmaI/netI    0.0225
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            16679
_diffrn_reflns_theta_full        27.50
_diffrn_reflns_theta_max         27.50
_diffrn_reflns_theta_min         2.32
_diffrn_source_current           30
_diffrn_source_voltage           50
_diffrn_standards_decay_%        0.00
_exptl_absorpt_coefficient_mu    4.098
_exptl_absorpt_correction_T_max  0.541
_exptl_absorpt_correction_T_min  0.231
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Sheldrick, 1996)'
_exptl_crystal_colour            red
_exptl_crystal_density_diffrn    1.411
_exptl_crystal_density_method    not-measured
_exptl_crystal_description       prism
_exptl_crystal_F_000             586
_exptl_crystal_size_max          0.37
_exptl_crystal_size_mid          0.285
_exptl_crystal_size_min          0.15
_refine_diff_density_max         1.683
_refine_diff_density_min         -0.994
_refine_diff_density_rms         0.067
_refine_ls_extinction_coef       0.00141(16)
_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   0.999
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     324
_refine_ls_number_reflns         6145
_refine_ls_number_restraints     89
_refine_ls_restrained_S_all      1.014
_refine_ls_R_factor_all          0.0199
_refine_ls_R_factor_gt           0.0190
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.01P)^2^+1.63P], P=(max(Fo^2^,0)+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0441
_refine_ls_wR_factor_ref         0.0445
_reflns_number_gt                5930
_reflns_number_total             6145
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja067011ysi20061102_122010.cif
_cod_data_source_block           Cp*Ta(n-Bu)2[N(iPr)C(Me)N(iPr)]
_cod_database_code               4111239