An Ylide-like Phosphasilene and Striking Formation of a 4π-Electron, Resonance-Stabilized 2,4-Disila-1,3-diphosphacyclobutadiene
Shigeyoshi Inoue; Wenyuan, Wang; Carsten Präsang; Matthew Asay; Elisabeth Irran; Matthias Driess; Journal of the American Chemical Society 133 (2011) 2868–2871; doi:10.1021/ja200462y

data_4105718
_publ_section_title
;
 An Ylide-like Phosphasilene and Striking Formation of a 4\p-Electron,
 Resonance-Stabilized 2,4-Disila-1,3-diphosphacyclobutadiene
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              2868
_journal_page_last               2871
_journal_paper_doi               10.1021/ja200462y
_journal_volume                  133
_journal_year                    2011
_chemical_formula_sum            'C21 H41 N2 P Si3'
_chemical_formula_weight         436.80
_space_group_IT_number           61
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method
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CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.42 (release 29-05-2009 CrysAlis171 .NET)
(compiled May 29 2009,17:40:42)
;
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   19.3556(7)
_cell_length_b                   14.2399(4)
_cell_length_c                   19.9777(6)
_cell_measurement_reflns_used    3386
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      32.4073
_cell_measurement_theta_min      3.3697
_cell_volume                     5506.3(3)
_computing_cell_refinement
;
CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.66 (release 28-04-2010 CrysAlis171 .NET)
(compiled Apr 28 2010,14:27:37)
;
_computing_data_collection
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CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.66 (release 28-04-2010 CrysAlis171 .NET)
(compiled Apr 28 2010,14:27:37)
;
_computing_data_reduction
;
CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.66 (release 28-04-2010 CrysAlis171 .NET)
(compiled Apr 28 2010,14:27:37)
;
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Xcalibur, Sapphire3'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enhance (Mo) X-ray Source'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0961
_diffrn_reflns_av_sigmaI/netI    0.1216
_diffrn_reflns_limit_h_max       23
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            19912
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         3.51
_exptl_absorpt_coefficient_mu    0.239
_exptl_absorpt_correction_T_max  0.9627
_exptl_absorpt_correction_T_min  0.9125
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.66 (release 28-04-2010 CrysAlis171 .NET)
(compiled Apr 28 2010,14:27:37)
empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.054
_exptl_crystal_description       plate
_exptl_crystal_F_000             1904
_exptl_crystal_size_max          0.39
_exptl_crystal_size_mid          0.36
_exptl_crystal_size_min          0.16
_refine_diff_density_max         0.316
_refine_diff_density_min         -0.214
_refine_diff_density_rms         0.050
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.906
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     287
_refine_ls_number_reflns         4836
_refine_ls_number_restraints     18
_refine_ls_restrained_S_all      0.905
_refine_ls_R_factor_all          0.1270
_refine_ls_R_factor_gt           0.0571
_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^)+(0.0364P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0889
_refine_ls_wR_factor_ref         0.1032
_reflns_number_gt                2750
_reflns_number_total             4836
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja200462y_si_003.cif
_cod_data_source_block           in28a
_cod_database_code               4105718