Regioselective [2+2] and [4+2] cycloaddition reactivity in an asymmetric niobium(bisimido) moiety towards unsaturated organic molecules.
Obenhuber, A. H.; Gianetti, T. L.; Bergman, R. G.; Arnold, J.; Chemical communications (Cambridge, England) 51 (2014) 1278–1281; doi:10.1039/c4cc07851a

data_7116194
_publ_section_title
;
 Regioselective [2+2] and [4+2] cycloaddition reactivity in an asymmetric
 niobium(bisimido) moiety towards unsaturated organic molecules.
;
_journal_issue                   7
_journal_name_full
'Chemical communications (Cambridge, England)'
_journal_page_first              1278
_journal_page_last               1281
_journal_paper_doi               10.1039/c4cc07851a
_journal_volume                  51
_journal_year                    2014
_chemical_formula_moiety         'C48 H61 Br0 Cl N3 Nb O'
_chemical_formula_sum            'C48 H61 Br0 Cl N3 Nb O'
_chemical_formula_weight         824.36
_chemical_name_common            'Complex 2'
_chemical_properties_physical    'Air-sensitive, Moisture-sensitive'
_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_update_record
;
2014-09-28 deposited with the CCDC.
2014-11-28 downloaded from the CCDC.
;
_cell_angle_alpha                96.454(4)
_cell_angle_beta                 102.126(3)
_cell_angle_gamma                91.320(4)
_cell_formula_units_Z            4
_cell_length_a                   11.3526(7)
_cell_length_b                   19.7589(12)
_cell_length_c                   20.1301(13)
_cell_measurement_reflns_used    9576
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      25.42
_cell_measurement_theta_min      2.21
_cell_volume                     4381.7(5)
_computing_cell_refinement       'Bruker APEX2 v.2011.4'
_computing_data_collection       'Bruker APEX2 v.2011.4'
_computing_data_reduction        'Bruker APEX2 v.2011.4'
_computing_molecular_graphics    ORTEP-32
_computing_publication_material  WinGX
_computing_structure_refinement  SHELXL-97
_computing_structure_solution    SIR-92
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 8.366
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Bruker APEX-I 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  0.0667
_diffrn_reflns_av_sigmaI/netI    0.0617
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       23
_diffrn_reflns_limit_k_min       -23
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            84384
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.47
_diffrn_reflns_theta_min         1.38
_exptl_absorpt_coefficient_mu    0.373
_exptl_absorpt_correction_T_max  0.9816
_exptl_absorpt_correction_T_min  0.9224
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.250
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needdle
_exptl_crystal_F_000             1744
_exptl_crystal_size_max          0.22
_exptl_crystal_size_mid          0.06
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.504
_refine_diff_density_min         -0.415
_refine_diff_density_rms         0.075
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.024
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     999
_refine_ls_number_reflns         16211
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.024
_refine_ls_R_factor_all          0.0649
_refine_ls_R_factor_gt           0.0399
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0284P)^2^+3.2528P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0779
_refine_ls_wR_factor_ref         0.0876
_reflns_number_gt                11965
_reflns_number_total             16211
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c4cc07851a2.cif
_cod_data_source_block           (1)
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
according to
/usr/data/users/saulius/crontab/automatic-downloads/rss-feeds/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 2935 2014-11-11 08:27:57Z andrius 
;
_cod_original_sg_symbol_H-M      P-1
_cod_database_code               7116194