Diphosphiranium (P2C) or Diphosphetanium (P2C2) Cyclic Cations: Different Fates for the Electrophile-Initiated Cyclodimerization of a Phosphaalkene
Joshua I. Bates; Derek P. Gates; Journal of the American Chemical Society 128 (2006) 15998–15999; doi:10.1021/ja0667662

data_4111225
_publ_section_title
;
 Diphosphiranium (P2C) or Diphosphetanium (P2C2) Cyclic Cations: Different
 Fates for the Electrophile-Initiated Cyclodimerization of a Phosphaalkene
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              15998
_journal_page_last               15999
_journal_paper_doi               10.1021/ja0667662
_journal_volume                  128
_journal_year                    2006
_chemical_formula_moiety         'C19 H41 P2, I'
_chemical_formula_sum            'C19 H41 I P2'
_chemical_formula_weight         458.36
_space_group_IT_number           29
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2ac'
_symmetry_space_group_name_H-M   'P c a 21'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   19.6306(7)
_cell_length_b                   9.7464(3)
_cell_length_c                   23.6322(7)
_cell_measurement_reflns_used    8360
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      27.83
_cell_measurement_theta_min      2.49
_cell_volume                     4521.5(3)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type  'Bruker X8 APEX'
_diffrn_measurement_method       'area detector'
_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  0.0282
_diffrn_reflns_av_sigmaI/netI    0.0336
_diffrn_reflns_limit_h_max       25
_diffrn_reflns_limit_h_min       -25
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       31
_diffrn_reflns_limit_l_min       -30
_diffrn_reflns_number            31854
_diffrn_reflns_theta_full        27.93
_diffrn_reflns_theta_max         27.93
_diffrn_reflns_theta_min         2.09
_exptl_absorpt_coefficient_mu    1.556
_exptl_absorpt_correction_T_max  0.733
_exptl_absorpt_correction_T_min  0.507
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.347
_exptl_crystal_description       irregular
_exptl_crystal_F_000             1904
_exptl_crystal_size_max          0.5
_exptl_crystal_size_mid          0.5
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.593
_refine_diff_density_min         -0.483
_refine_diff_density_rms         0.061
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.024(8)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.018
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     439
_refine_ls_number_reflns         10524
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.018
_refine_ls_R_factor_all          0.0270
_refine_ls_R_factor_gt           0.0235
_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^)+(0.0252P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0507
_refine_ls_wR_factor_ref         0.0520
_reflns_number_gt                9787
_reflns_number_total             10524
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja0667662si20061031_012143.cif
_cod_data_source_block           new
_cod_database_code               4111225