Synthesis and structures of novel chiral lithium amidinates and mono- and di-lithium (1R,2R)-(−)-1,2-(NHSiMe3)2C6H10
Jian-Feng Li; Lin-Hong Weng; Xue-Hong Wei; Dian-Sheng Liu; J. Chem. Soc., Dalton Trans.  (2002) 1401–1405; doi:10.1039/b106992f

data_7011036
_publ_section_title
;
 Synthesis and structures of novel chiral lithium amidinates and mono-
 and di-lithium (1R,2R)-(&#x2212;)-1,2-(NHSiMe3)2C6H10
;
_journal_issue                   7
_journal_name_full               'J. Chem. Soc., Dalton Trans.'
_journal_page_first              1401
_journal_page_last               1405
_journal_paper_doi               10.1039/b106992f
_journal_year                    2002
_chemical_formula_sum            'C24 H56 Li4 N4 Si4'
_chemical_formula_weight         540.85
_chemical_name_systematic
; 
? 
;
_space_group_IT_number           144
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_Hall  'P 31'
_symmetry_space_group_name_H-M   'P 31'
_atom_sites_solution_hydrogens
;
DIFMAP & GEOM (H atoms of SiMe3 were located by geom and rest were found 
from difmap
;
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            3
_cell_length_a                   10.5111(14)
_cell_length_b                   10.5111(14)
_cell_length_c                   27.891(5)
_cell_measurement_reflns_used    885
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      24.208
_cell_measurement_theta_min      2.672
_cell_volume                     2668.6(7)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_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  0.0370
_diffrn_reflns_av_sigmaI/netI    0.0515
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       32
_diffrn_reflns_limit_l_min       -33
_diffrn_reflns_number            11141
_diffrn_reflns_theta_full        25.03
_diffrn_reflns_theta_max         25.03
_diffrn_reflns_theta_min         2.19
_diffrn_standards_decay_%        2.45
_exptl_absorpt_coefficient_mu    0.184
_exptl_absorpt_correction_T_max  0.9468
_exptl_absorpt_correction_T_min  0.9383
_exptl_crystal_density_diffrn    1.010
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             888
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.30
_refine_diff_density_max         0.222
_refine_diff_density_min         -0.228
_refine_diff_density_rms         0.049
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.03(16)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.076
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     405
_refine_ls_number_reflns         6280
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.075
_refine_ls_R_factor_all          0.0770
_refine_ls_R_factor_gt           0.0591
_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^)+(0.0675P)^2^+1.7060P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1440
_refine_ls_wR_factor_ref         0.1536
_reflns_number_gt                5037
_reflns_number_total             6280
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b106992f.txt
_cod_data_source_block           compound3
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Trigonal' changed to 'trigonal' 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_cell_volume        2668.7(7)
_cod_original_sg_symbol_H-M      'P3(1)   '
_cod_database_code               7011036