Preparation of cyclophanes by room-temperature ring-closing alkyne metathesis with imidazolin-2-iminato tungsten alkylidyne complexes.
Beer, Stephan; Brandhorst, Kai; Grunenberg, Jörg; Hrib, Cristian G.; Jones, Peter G.; Tamm, Matthias; Organic letters 10 (2008) 981–984; doi:10.1021/ol800154y

data_1504589
_publ_section_title
;
 Preparation of cyclophanes by room-temperature ring-closing alkyne
 metathesis with imidazolin-2-iminato tungsten alkylidyne complexes.
;
_journal_issue                   5
_journal_name_full               'Organic letters'
_journal_page_first              981
_journal_page_last               984
_journal_paper_doi               10.1021/ol800154y
_journal_volume                  10
_journal_year                    2008
_chemical_formula_sum            'C28 H32 O4'
_chemical_formula_weight         432.54
_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                 90.586(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   12.9818(8)
_cell_length_b                   9.8352(7)
_cell_length_c                   8.9683(6)
_cell_measurement_reflns_used    3761
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      28
_cell_measurement_theta_min      2
_cell_volume                     1145.00(13)
_computing_cell_refinement       'Bruker APEX2'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker APEX2'
_computing_molecular_graphics    'Bruker XP'
_computing_publication_material  SHELXL-97
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'Bruker APEX2 CCD'
_diffrn_measurement_method       '\w- and \f-scans'
_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  0.0707
_diffrn_reflns_av_sigmaI/netI    0.0632
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            15577
_diffrn_reflns_theta_full        28.00
_diffrn_reflns_theta_max         28.28
_diffrn_reflns_theta_min         1.57
_diffrn_standards_decay_%        0
_exptl_absorpt_coefficient_mu    0.082
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.255
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       tablet
_exptl_crystal_F_000             464
_exptl_crystal_size_max          0.18
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.366
_refine_diff_density_min         -0.368
_refine_diff_density_rms         0.091
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.179
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     145
_refine_ls_number_reflns         2813
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.179
_refine_ls_R_factor_all          0.1229
_refine_ls_R_factor_gt           0.0843
_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^)+(0.0797P)^2^+2.9329P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2317
_refine_ls_wR_factor_ref         0.2488
_reflns_number_gt                1878
_reflns_number_total             2813
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol800154y-file003.cif
_cod_data_source_block           steph91
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               1504589