Ring Contraction of 1,2,4,5,7,8-Hexaoxa-3-silonanes by Selective Reduction of COOSi Fragments. Synthesis of New Silicon-Containing Rings, 1,3,5,6-Tetraoxa-2-silepanes
Alexander O. Terent'ev; Maxim M. Platonov; Anna I. Tursina; Vladimir V. Chernyshev; Gennady I. Nikishin; Journal of Organic Chemistry 74 (2009) 1917–1922; doi:10.1021/jo8023957

data_4024360
_publ_contact_author             V.V.Chernyshev
_publ_contact_author_address
;
      Department of Chemistry 
      Moscow State University
      119991 Moscow
      Russia
;
_publ_contact_author_email       vladimir@struct.chem.msu.ru
_publ_contact_author_fax         '+ 7-095-9390898'
_publ_contact_author_name        'Dr. Vladimir V. Chernyshev'
_publ_contact_author_phone       '+ 7-095-9393654'
_publ_section_title
;
Ring Contraction of 1,2,4,5,7,8-Hexaoxa-3-silonanes by Selective Reduction
of COOSi Fragments. Synthesis of New Silicon-Containing Rings,
1,3,5,6-Tetraoxa-2-silepanes
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              1917
_journal_page_last               1922
_journal_paper_doi               10.1021/jo8023957
_journal_volume                  74
_journal_year                    2009
_chemical_formula_moiety         'C26 H50 O4 Si'
_chemical_formula_sum            'C26 H50 O4 Si'
_chemical_formula_weight         454.75
_chemical_name_systematic
; 
28,28-dimethyl-13,14,27,29-tetraoxa-28-siladispiro[11.2.11.3]nonacosane
;
_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                 93.844(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   8.432(2)
_cell_length_b                   20.859(3)
_cell_length_c                   31.946(5)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    294(2)
_cell_measurement_theta_max      29.89
_cell_measurement_theta_min      23.45
_cell_volume                     5606.1(18)
_computing_cell_refinement       'CAD4 Express (Enraf Nonius, 1994)'
_computing_data_collection       'CAD4 Express (Enraf Nonius, 1994)'
_computing_data_reduction        'XCAD4 (Harms & Wocadlo, 1995)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      294(2)
_diffrn_detector                 'scintillation LiI'
_diffrn_detector_dtime           1.195
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device       '\k-geometry diffractometer'
_diffrn_measurement_device_type  'Enraf Nonius CAD4'
_diffrn_measurement_method       'non-profiled omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.1047
_diffrn_reflns_av_sigmaI/netI    0.3988
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       34
_diffrn_reflns_limit_l_min       -34
_diffrn_reflns_number            8159
_diffrn_reflns_theta_full        57.16
_diffrn_reflns_theta_max         57.16
_diffrn_reflns_theta_min         2.53
_diffrn_source                   'Enraf Nonius FR590'
_diffrn_standards_decay_%        5
_diffrn_standards_interval_time  120
_diffrn_standards_number         2
_exptl_absorpt_coefficient_mu    0.936
_exptl_absorpt_correction_T_max  0.985
_exptl_absorpt_correction_T_min  0.899
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details
;
North A.C.T., Phillips D.C. & Mathews F.S. (1968) Acta. Cryst. A24, 351
Number of psi-scan sets used was   4
Theta correction was applied.
Averaged transmission function was used.
No Fourier smoothing was applied.
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.078
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             2016
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.357
_refine_diff_density_min         -0.293
_refine_diff_density_rms         0.056
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.894
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     559
_refine_ls_number_reflns         7551
_refine_ls_number_restraints     61
_refine_ls_restrained_S_all      0.870
_refine_ls_R_factor_all          0.3184
_refine_ls_R_factor_gt           0.0844
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0980P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1809
_refine_ls_wR_factor_ref         0.2572
_reflns_number_gt                1794
_reflns_number_total             7551
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo8023957_si_002_1.cif
_cod_data_source_block           ioh26mono
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               4024360