Reactivity of Ar'GeGeAr' (Ar' = C6H3-2,6-Dipp2, Dipp = C6H3-2,6-iPr2) toward Alkynes: Isolation of a Stable Digermacyclobutadiene
Chunming Cui; Marilyn M. Olmstead; Philip P. Power; Journal of the American Chemical Society 126 (2004) 5062–5063; doi:10.1021/ja0318481

data_4112475
_publ_section_title
;
 Reactivity of Ar'GeGeAr' (Ar' = C6H3-2,6-Dipp2, Dipp = C6H3-2,6-iPr2)
 toward Alkynes: Isolation of a Stable Digermacyclobutadiene
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              5062
_journal_page_last               5063
_journal_paper_doi               10.1021/ja0318481
_journal_volume                  126
_journal_year                    2004
_chemical_formula_moiety         '2(C70 H94 Ge2 Si2), 0.25(C5 H12)'
_chemical_formula_sum            'C71.25 H97 Ge2 Si2'
_chemical_formula_weight         1154.85
_space_group_IT_number           9
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'I -2ya'
_symmetry_space_group_name_H-M   'I 1 a 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                 104.211(6)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   33.299(8)
_cell_length_b                   13.209(3)
_cell_length_c                   38.495(13)
_cell_measurement_reflns_used    981
_cell_measurement_temperature    91(2)
_cell_measurement_theta_max      20.0
_cell_measurement_theta_min      2.5
_cell_volume                     16414(8)
_computing_cell_refinement       'SMART 5.054'
_computing_data_collection       'SMART 5.054 (Bruker, 2002)'
_computing_data_reduction        'SAINT 6.36A (Bruker, 2002)'
_computing_molecular_graphics    'SHELXTL 5.1, XP (Sheldrick, 1994)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      91(2)
_diffrn_detector_area_resol_mean 8.3
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker SMART 1000'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'normal-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0500
_diffrn_reflns_av_sigmaI/netI    0.0609
_diffrn_reflns_limit_h_max       43
_diffrn_reflns_limit_h_min       -43
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       49
_diffrn_reflns_limit_l_min       -49
_diffrn_reflns_number            91879
_diffrn_reflns_theta_full        27.48
_diffrn_reflns_theta_max         27.48
_diffrn_reflns_theta_min         1.09
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.792
_exptl_absorpt_correction_T_max  0.877
_exptl_absorpt_correction_T_min  0.769
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS 2.10 (Sheldrick, 2003)'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    0.935
_exptl_crystal_description       block
_exptl_crystal_F_000             4932
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.17
_refine_diff_density_max         1.999
_refine_diff_density_min         -0.855
_refine_diff_density_rms         0.195
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.54(1)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.061
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     1397
_refine_ls_number_reflns         36987
_refine_ls_number_restraints     15
_refine_ls_restrained_S_all      1.063
_refine_ls_R_factor_all          0.0900
_refine_ls_R_factor_gt           0.0713
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1593P)^2^+50.0101P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2209
_refine_ls_wR_factor_ref         0.2380
_reflns_number_gt                30438
_reflns_number_total             36987
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ja0318481si20031219_053802.cif
_cod_data_source_block           mn1547
_cod_original_sg_symbol_H-M      'I a'
_cod_database_code               4112475