Synthesis and structural characterisation of a novel phosphine-borane-stabilised dicarbanion and an unusual bis(phosphine-borane).
Izod, Keith; McFarlane, William; Tyson, Brent V; Clegg, William; Harrington, Ross W; Chemical communications (Cambridge, England)  (2004) 570–571; doi:10.1039/b315068b

data_7102504
_publ_section_title
;
 Synthesis and structural characterisation of a novel
 phosphine-borane-stabilised dicarbanion and an unusual
 bis(phosphine-borane).
;
_journal_issue                   5
_journal_name_full               'Chemical communications (Cambridge, England)'
_journal_page_first              570
_journal_page_last               571
_journal_paper_doi               10.1039/b315068b
_journal_year                    2004
_chemical_formula_moiety         'C22 H58 B2 P2 Si2'
_chemical_formula_sum            'C22 H58 B2 P2 Si2'
_chemical_formula_weight         462.42
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 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                 107.859(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   14.1618(11)
_cell_length_b                   6.9841(5)
_cell_length_c                   16.5204(12)
_cell_measurement_reflns_used    5915
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      28.5
_cell_measurement_theta_min      2.3
_cell_volume                     1555.3(2)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL and local programs'
_computing_structure_refinement  'Bruker SHELXTL'
_computing_structure_solution    'Bruker SHELXTL'
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Bruker SMART 1K CCD diffractometer'
_diffrn_measurement_method       'thin-slice \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0337
_diffrn_reflns_av_sigmaI/netI    0.0362
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            8510
_diffrn_reflns_theta_full        24.99
_diffrn_reflns_theta_max         24.99
_diffrn_reflns_theta_min         1.66
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.224
_exptl_absorpt_correction_T_max  0.978
_exptl_absorpt_correction_T_min  .957
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    0.987
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             516
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.343
_refine_diff_density_min         -0.173
_refine_diff_density_rms         0.046
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.093
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     133
_refine_ls_number_reflns         2728
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.093
_refine_ls_R_factor_all          0.0557
_refine_ls_R_factor_gt           0.0398
_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^)+(0.0463P)^2^+0.6261P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0964
_refine_ls_wR_factor_ref         0.1055
_reflns_number_gt                2160
_reflns_number_total             2728
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            b315068b.txt
_cod_data_source_block           ki126
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               7102504