Thermal [2 + 2]-Cycloaddition of Ketenes with Chiral Enol Ethers: Route to Densely Substituted Cyclobutanones.
Rullière, Pauline; Grisel, Julien; Poittevin, Clément; Cividino, Pascale; Carret, Sébastien; Poisson, Jean-François; Organic letters 18 (2016) 2824–2827; doi:10.1021/acs.orglett.6b01058

data_1543364
_publ_section_title
;
 Thermal [2 + 2]-Cycloaddition of Ketenes with Chiral Enol Ethers: Route
 to Densely Substituted Cyclobutanones.
;
_journal_issue                   12
_journal_name_full               'Organic letters'
_journal_page_first              2824
_journal_page_last               2827
_journal_paper_doi               10.1021/acs.orglett.6b01058
_journal_volume                  18
_journal_year                    2016
_chemical_formula_moiety         'C28 H48 O3 Si2'
_chemical_formula_sum            'C28 H48 O3 Si2'
_chemical_formula_weight         488.84
_space_group_crystal_system      monoclinic
_space_group_IT_number           15
_space_group_name_Hall           '-C 2yc'
_space_group_name_H-M_alt        'C 1 2/c 1'
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_date             2016-02-05
_audit_creation_method
;
  Olex2 1.1
  (compiled Sep 28 2011 20:36:17, GUI svn.r3906)
;
_cell_angle_alpha                90.00
_cell_angle_beta                 107.18(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   48.523(10)
_cell_length_b                   6.2947(13)
_cell_length_c                   20.561(4)
_cell_measurement_reflns_used    27431
_cell_measurement_temperature    200.0
_cell_measurement_theta_max      25.00
_cell_measurement_theta_min      2.00
_cell_volume                     6000(2)
_computing_cell_refinement       EvalCCD
_computing_data_collection       Collect
_computing_data_reduction        EvalCCD
_computing_molecular_graphics
;
O. V. Dolomanov, L. J. Bourhis, R. J. Gildea, J. A. K. Howard and H. Puschmann,
OLEX2: a complete structure solution, refinement and analysis program.
J. Appl. Cryst. (2009). 42, 339-341.
;
_computing_publication_material
;
O. V. Dolomanov, L. J. Bourhis, R. J. Gildea, J. A. K. Howard and H. Puschmann,
OLEX2: a complete structure solution, refinement and analysis program.
J. Appl. Cryst. (2009). 42, 339-341.
;
_computing_structure_refinement
;
SHELXL, G.M. Sheldrick, Acta Cryst.
(2008). A64, 112-122
;
_computing_structure_solution
;
SHELXD, G.M. Sheldrick, Acta Cryst.
(2008). A64, 112-122
;
_diffrn_ambient_temperature      200.0
_diffrn_detector                 'CCD area detector'
_diffrn_detector_type            KappaCCD
_diffrn_measured_fraction_theta_full 0.983
_diffrn_measured_fraction_theta_max 0.983
_diffrn_measurement_device_type  'Bruker-AXS-enraf-nonius KappaCCD'
_diffrn_measurement_method       'Phi and omega scans'
_diffrn_radiation_detector       CCD
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0364
_diffrn_reflns_av_unetI/netI     0.0357
_diffrn_reflns_limit_h_max       57
_diffrn_reflns_limit_h_min       -57
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            27431
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         2.00
_diffrn_source                   'Enraf Nonius FR590'
_diffrn_source_target            Mo
_diffrn_source_type              'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    0.143
_exptl_absorpt_correction_T_max  1
_exptl_absorpt_correction_T_min  0.806548
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2004/1 (Bruker,2004) was used for absorption correction.
R(int) was 0.1007 before and 0.0323 after correction.
The Ratio of minimum to maximum transmission is 0.8065.
The \l/2 correction factor is 0.0015.
;
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.082
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             2144
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.35
_exptl_crystal_size_min          0.12
_refine_diff_density_max         0.449
_refine_diff_density_min         -0.232
_refine_diff_density_rms         0.048
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.081
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     312
_refine_ls_number_reflns         5211
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.085
_refine_ls_R_factor_all          0.0742
_refine_ls_R_factor_gt           0.0435
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0445P)^2^+8.7386P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1004
_refine_ls_wR_factor_ref         0.1173
_reflns_number_gt                3774
_reflns_number_total             5211
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol6b01058_si_002.cif
_cod_data_source_block           nanny
_cod_depositor_comments          'Adding full bibliography for 1543364.cif.'
_cod_database_code               1543364