Synthesis and crystal structures of novel 1-aza-2-silacyclobut-3-enes
Bowen, Richard J.; Fernandes, Manuel A.; Hitchcock, Peter B.; Lappert, Michael F.; Layh, Marcus; Journal of the Chemical Society, Dalton Transactions  (2002) 3253–; doi:10.1039/b202629p

data_7011654
_publ_section_title
;
 Synthesis and crystal structures of novel 1-aza-2-silacyclobut-3-enes
;
_journal_issue                   16
_journal_name_full
'Journal of the Chemical Society, Dalton Transactions'
_journal_page_first              3253
_journal_paper_doi               10.1039/b202629p
_journal_year                    2002
_chemical_formula_moiety         'C66 H122 Li2 N4 P4 Si8'
_chemical_formula_sum            'C66 H122 Li2 N4 P4 Si8'
_chemical_formula_weight         1334.16
_chemical_name_systematic
;
Bis-{(P,P,P',P'-tetramethylethylenediphosphine)-(1-(2,6-dimethylphenyl)-
2,2-bis(trimethylsilyl)-3-(trimethylsilyl-4-(2,6-dimethylphenyl)amido-1-aza-2-
sila-cyclobut-3-ene-N)-lithium}
;
_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
_cell_angle_alpha                100.496(3)
_cell_angle_beta                 100.679(3)
_cell_angle_gamma                111.366(3)
_cell_formula_units_Z            1
_cell_length_a                   10.1824(16)
_cell_length_b                   12.756(2)
_cell_length_c                   18.168(3)
_cell_measurement_temperature    173(2)
_cell_volume                     2077.6(6)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SHELXTL'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.968
_diffrn_measured_fraction_theta_max 0.968
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega 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  0.0172
_diffrn_reflns_av_sigmaI/netI    0.0431
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            14560
_diffrn_reflns_theta_full        28.32
_diffrn_reflns_theta_max         28.32
_diffrn_reflns_theta_min         1.19
_exptl_absorpt_coefficient_mu    0.243
_exptl_absorpt_correction_T_max  0.9577
_exptl_absorpt_correction_T_min  0.9092
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details
;
SADABS: Area-Detector Absorption 
Correction. (1996)  Siemens Industrial Automation, Inc.: 
Madison, WI.. 
;
_exptl_crystal_colour            Yellow
_exptl_crystal_density_diffrn    1.066
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Rectangular
_exptl_crystal_F_000             724
_exptl_crystal_preparation       'grown from hexane at -20 C'
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.28
_exptl_crystal_size_min          0.18
_refine_diff_density_max         0.369
_refine_diff_density_min         -0.305
_refine_diff_density_rms         0.054
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.018
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     396
_refine_ls_number_reflns         10016
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.018
_refine_ls_R_factor_all          0.0707
_refine_ls_R_factor_gt           0.0436
_refine_ls_shift/su_max          0.016
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0763P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1160
_refine_ls_wR_factor_ref         0.1323
_reflns_number_gt                7063
_reflns_number_total             10016
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b202629p.txt
_cod_data_source_block           li4rtf_s
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
according to '/home/adriana/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from
2010-06-29.

'_exptl_absorpt_correction_type' value 'Empirical' changed to
'empirical' according to
'/home/adriana/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 1555 2011-01-17 13:19:09Z saulius 
;
_cod_original_cell_volume        2077.5(6)
_cod_original_sg_symbol_H-M      P-1
_cod_database_code               7011654