Total Synthesis of (\±)-Phomactin B2 via an Intramolecular Cyclohexadienone Annulation of a Chromium Carbene Complex
Jie Huang; Chunrui Wu; William D. Wulff; Journal of the American Chemical Society 129 (2007) 13366–13367; doi:10.1021/ja074275r

data_4110120
_publ_section_title
;
 Total Synthesis of (\+-)-Phomactin B2 via an Intramolecular
 Cyclohexadienone Annulation of a Chromium Carbene Complex
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              13366
_journal_page_last               13367
_journal_paper_doi               10.1021/ja074275r
_journal_volume                  129
_journal_year                    2007
_chemical_formula_sum            'C28 H46 O3 Si'
_chemical_formula_weight         458.74
_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                 107.07(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.384(3)
_cell_length_b                   12.584(3)
_cell_length_c                   18.686(4)
_cell_measurement_temperature    173(2)
_cell_volume                     2783.7(12)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.971
_diffrn_measured_fraction_theta_max 0.971
_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  0.0463
_diffrn_reflns_av_sigmaI/netI    0.0471
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            27573
_diffrn_reflns_theta_full        28.24
_diffrn_reflns_theta_max         28.24
_diffrn_reflns_theta_min         1.72
_exptl_absorpt_coefficient_mu    0.109
_exptl_crystal_density_diffrn    1.095
_exptl_crystal_F_000             1008
_exptl_crystal_size_max          0.8
_exptl_crystal_size_mid          0.3
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.345
_refine_diff_density_min         -0.351
_refine_diff_density_rms         0.048
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.011
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     317
_refine_ls_number_reflns         6693
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.011
_refine_ls_R_factor_all          0.0857
_refine_ls_R_factor_gt           0.0495
_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^)+(0.1000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1429
_refine_ls_wR_factor_ref         0.1602
_reflns_number_gt                4467
_reflns_number_total             6693
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja074275rrom20070612_031125.cif
_cod_data_source_block           wulff07
_cod_original_cell_volume        2783.9(10)
_cod_database_code               4110120