An unprecedented α-C‒C agostic interaction in a cyclopropyl tris(pyrazolyl)boratoniobium complex
Jaffart, Joëlle; Etienne, Michel; Reinhold, Meike; McGrady, John E.; Maseras, Feliu; Chemical Communications (Cambridge, United Kingdom)  (2003) 876–877; doi:10.1039/b300324h

data_7104054
_publ_section_title
;
 An unprecedented \a-C--C agostic interaction in a cyclopropyl
 tris(pyrazolyl)boratoniobium complex
;
_journal_coden_ASTM              CHCOFS
_journal_issue                   7
_journal_name_full
;
 Chemical Communications (Cambridge, United Kingdom)
;
_journal_page_first              876
_journal_page_last               877
_journal_paper_doi               10.1039/b300324h
_journal_year                    2003
_chemical_formula_moiety         ' C22 H33 Nb1 Br1 N6 B1 '
_chemical_formula_sum            'C22 H33 B Br N6 Nb'
_chemical_formula_weight         565.17
_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   'Geometric or located (Fourier difference)'
_atom_sites_solution_primary     'Direct_Methods SIR92'
_audit_creation_date             99-10-11
_audit_creation_method           CRYSTALS
_cell_angle_alpha                96.16(2)
_cell_angle_beta                 106.91(2)
_cell_angle_gamma                119.21(2)
_cell_formula_units_Z            2
_cell_length_a                   10.747(2)
_cell_length_b                   10.852(2)
_cell_length_c                   13.211(2)
_cell_measurement_reflns_used    5000
_cell_measurement_temperature    160
_cell_measurement_theta_max      24.15
_cell_measurement_theta_min      2.2
_cell_volume                     1228(1)
_computing_cell_refinement       ' STOE IPDS '
_computing_data_collection       ' STOE IPDS '
_computing_data_reduction
;
STOE X RED
;
_computing_molecular_graphics
;
CAMERON (Watkin, Prout & Pearce, 1996)
;
_computing_publication_material
;
CRYSTALS Issue 10 (Watkin, Prout, Carruthers & Betteridge, 1996)
;
_computing_structure_refinement
;
CRYSTALS Issue 10 (Watkin, Prout, Carruthers & Betteridge, 1996)
;
_computing_structure_solution    'SIR92 (Giacovazzo et al, 1992)'
_diffrn_ambient_temperature      160
_diffrn_measurement_device       '  STOE IPDS '
_diffrn_measurement_method       'phi rotation'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.00
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            7205
_diffrn_reflns_theta_max         0.00
_diffrn_reflns_theta_min         0.00
_diffrn_standards_decay_%        0.00
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    2.10
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            ' orange '
_exptl_crystal_density_diffrn    1.53
_exptl_crystal_description       ' block '
_exptl_crystal_F_000             570.83
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.17
_exptl_crystal_size_min          0.37
_refine_diff_density_max         1.31
_refine_diff_density_min         -2.11
_refine_ls_extinction_method     None
_refine_ls_goodness_of_fit_obs   1.0936
_refine_ls_hydrogen_treatment
;
H atoms placed geometrically after each cycle, except H1 to H32 located 
and refined isotropically with an equivalent Uiso

;
_refine_ls_matrix_type           full
_refine_ls_number_parameters     299
_refine_ls_number_reflns         5785
_refine_ls_R_factor_obs          0.0393
_refine_ls_shift/esd_max         0.000349
_refine_ls_structure_factor_coef F
_refine_ls_weighting_scheme
;
FULL NB(1, X'S, U'S) UNTIL C(55), H(1, X'S, U[ISO]) UNTIL H(32)
EQUIVALENCE H(1, U[ISO]) UNTIL H(32)
END

w = w'[1-(?F/6?(F))2]2. w' = 1/?(r=1,3)ArTr(x) where Ar are the coefficients 
for the Chebyshev polynomial Tr(x) with x = Fc/Fc(max) (Carruthers & 
Watkin, 1979)
coef 2.02       -2.32        1.18      -0.727      -0.114

;
_refine_ls_wR_factor_obs         0.0316
_reflns_limit_h_max              12
_reflns_limit_h_min              -12
_reflns_limit_k_max              12
_reflns_limit_k_min              -12
_reflns_limit_l_max              15
_reflns_limit_l_min              -15
_reflns_number_observed          5785
_reflns_number_total             7205
_reflns_observed_criterion       >3.00\?(I)
_cod_data_source_file            b300324h.txt
_cod_data_source_block           CRYSTALS_cif
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Triclinic ' changed to 'triclinic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 
;
_cod_original_sg_symbol_H-M      'P -1 '
_cod_original_formula_sum        ' C22 H33 Nb1 Br1 N6 B1 '
_cod_database_code               7104054