New Bonding Modes for Boraamidinate Ligands in Heavy Group 15 Complexes: Fluxional Behavior of the 1:2 Complexes, LiM[PhB(NtBu)2]2 (M = As, Sb, Bi)
Jari Konu; Maravanji S. Balakrishna; Tristram Chivers; Thomas W. Swaddle; Inorganic Chemistry 46 (2007) 2627–2636; doi:10.1021/ic0622757

data_4307794
_publ_contact_author             'Professor Tristram Chivers'
_publ_contact_author_email       chivers@ucalgary.ca
_publ_section_title
;
New Bonding Modes for Boraamidinate Ligands in Heavy Group 15 Complexes:
Fluxional Behavior of the 1:2 Complexes, LiM[PhB(NtBu)2]2 (M = As, Sb, Bi)
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              2627
_journal_page_last               2636
_journal_paper_doi               10.1021/ic0622757
_journal_volume                  46
_journal_year                    2007
_chemical_formula_moiety         'C28 H46 As B2 Li N4'
_chemical_formula_sum            'C28 H46 As B2 Li N4'
_chemical_formula_weight         542.17
_chemical_name_systematic
;
 ?
;
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/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                 134.22(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   25.990(5)
_cell_length_b                   8.6722(17)
_cell_length_c                   18.403(4)
_cell_measurement_reflns_used    9494
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      25.02
_cell_measurement_theta_min      3.39
_cell_volume                     2972.6(18)
_computing_cell_refinement       'HKL Scalepack (Otwinowski & Minor 1997)'
_computing_data_collection       'Collect (Nonius BV, 1997-2000)'
_computing_data_reduction        DENZO-SMN
_computing_molecular_graphics    'DIAMOND (Brandenburg & Berndt, 1999)'
_computing_publication_material  'WinGX v1.70-01 (L. J. Farrugia)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'KappaCCD (Nonius, FR540C)'
_diffrn_measurement_method       'phi\omega scans'
_diffrn_radiation_monochromator  'horizonally mounted graphite crystal'
_diffrn_radiation_source         'Enraf Nonius FR590D, fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0371
_diffrn_reflns_av_sigmaI/netI    0.0284
_diffrn_reflns_limit_h_max       30
_diffrn_reflns_limit_h_min       -30
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            9494
_diffrn_reflns_theta_full        25.02
_diffrn_reflns_theta_max         25.02
_diffrn_reflns_theta_min         3.39
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    1.166
_exptl_absorpt_correction_T_max  0.8003
_exptl_absorpt_correction_T_min  0.7067
_exptl_absorpt_correction_type   integration
_exptl_absorpt_process_details   'SADABS (SHELXTL-NT v5.1, Bruker)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.212
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1152
_exptl_crystal_size_max          0.32
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.436
_refine_diff_density_min         -0.437
_refine_diff_density_rms         0.062
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.157
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     166
_refine_ls_number_reflns         2620
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.157
_refine_ls_R_factor_all          0.0590
_refine_ls_R_factor_gt           0.0533
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0440P)^2^+10.8385P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1317
_refine_ls_wR_factor_ref         0.1342
_reflns_number_gt                2385
_reflns_number_total             2620
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic0622757si20070112_014747_6.cif
_cod_data_source_block           compound_3a
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               4307794