N,N′-Bis-Silylated Lithium Aryl Amidinates: Synthesis, Characterization, and the Gradual Transition of Coordination Mode from σ Toward π Originated by Crystal Packing Interactions
Aharonovich, Sinai; Kapon, Moshe; Botoshanski, Mark; Eisen, Moris S.; Organometallics 27 (2008) 1869–; doi:10.1021/om701216p

data_4071033
_publ_section_title
;
 N,N&#x2032;-Bis-Silylated Lithium Aryl Amidinates: Synthesis,
 Characterization, and the Gradual Transition of Coordination Mode from \s
 Toward \p Originated by Crystal Packing Interactions
;
_journal_issue                   8
_journal_name_full               Organometallics
_journal_page_first              1869
_journal_paper_doi               10.1021/om701216p
_journal_volume                  27
_journal_year                    2008
_chemical_formula_moiety         'C20 H41 Li1 N4 O1 Si2'
_chemical_formula_sum            'C20 H41 Li N4 O Si2'
_chemical_formula_weight         416.69
_chemical_name_common            Moris-77(litmdadim)
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/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                 107.04(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   16.327(3)
_cell_length_b                   13.136(3)
_cell_length_c                   26.795(5)
_cell_measurement_reflns_used    6849
_cell_measurement_temperature    230(1)
_cell_measurement_theta_max      22.89
_cell_measurement_theta_min      2.22
_cell_volume                     5494(2)
_computing_cell_refinement       'HKL Scalepack (Otwinowski & Minor 1997)'
_computing_data_collection       'Nonius (1997), KappaCCD Collect Program'
_computing_data_reduction
;
HKL Denzo and Scalepack (Otwinowski & Minor 1997)
;
_computing_molecular_graphics
;
Molecular Structure Corporation (1999). 
ORTEP. TEXRAY Structure Analysis Package. 
MSC, 3200 Research Forest Drive, The 
Woodlands,TX 77381, USA.
;
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution
;
S.Mackay, C.J.Gilmore, C.Edwards, M. Tremayne, N. Stuart, K.Shankland 
"maXus": a computer program for the solution and refinement of crystal 
structures from diffraction data University of Glasgow, Scotland, UK, 
Nonius BV, Delft, The Netherlands and MacScience Co. Ltd.,
Yokohama, Japan (1998)
;
_diffrn_ambient_temperature      230(1)
_diffrn_measured_fraction_theta_full 0.949
_diffrn_measured_fraction_theta_max 0.949
_diffrn_measurement_device_type  'Nonius KappaCCD'
_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  0.0633
_diffrn_reflns_av_sigmaI/netI    0.1435
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -28
_diffrn_reflns_number            12089
_diffrn_reflns_theta_full        22.89
_diffrn_reflns_theta_max         22.89
_diffrn_reflns_theta_min         1.74
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.144
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.007
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             1824
_exptl_crystal_size_max          0.48
_exptl_crystal_size_mid          0.48
_exptl_crystal_size_min          0.30
_refine_diff_density_max         0.592
_refine_diff_density_min         -0.195
_refine_diff_density_rms         0.052
_refine_ls_extinction_coef       0.0018(5)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   0.884
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     506
_refine_ls_number_reflns         7155
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.890
_refine_ls_R_factor_all          0.1598
_refine_ls_R_factor_gt           0.0745
_refine_ls_shift/su_max          0.004
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1013P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1830
_refine_ls_wR_factor_ref         0.1997
_reflns_number_gt                2873
_reflns_number_total             7157
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            om701216p-file003.cif
_cod_data_source_block           complex6
_cod_original_cell_volume        5494.5(21)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_original_formula_sum        'C20 H41 Li1 N4 O1 Si2'
_cod_database_code               4071033