Synthetic Studies on Furanosteroids: Construction of the Viridin Core Structure via Diels-Alder/retro-Diels-Alder and Vinylogous Mukaiyama Aldol-Type Reaction
Evans O. Onyango; Peter A. Jacobi; Journal of Organic Chemistry 77 (2012) 7411–7427; doi:10.1021/jo301232w

data_4027456
_publ_section_title
;
 Synthetic Studies on Furanosteroids: Construction of the Viridin Core
 Structure via Diels-Alder/retro-Diels-Alder and Vinylogous Mukaiyama
 Aldol-Type Reaction
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              7411
_journal_page_last               7427
_journal_paper_doi               10.1021/jo301232w
_journal_volume                  77
_journal_year                    2012
_chemical_formula_moiety         'C19 H18 O3'
_chemical_formula_sum            'C19 H18 O3'
_chemical_formula_weight         294.33
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      14
_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                 115.6220(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.49880(10)
_cell_length_b                   25.1729(4)
_cell_length_c                   8.50030(10)
_cell_measurement_reflns_used    9369
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      67.25
_cell_measurement_theta_min      3.51
_cell_volume                     1446.79(4)
_computing_cell_refinement       'APEX2 (BRUKER, V2010.11-3, 2010)'
_computing_data_collection       'COSMO (BRUKER, V1.61, 2009)'
_computing_data_reduction        'SAINT (BRUKER, V7.68A, 2010)'
_computing_molecular_graphics
'SHELXTL (Sheldrick, Acta Cryst. A64 2008, 112-122)'
_computing_publication_material
'SHELXTL (Sheldrick, Acta Cryst. A64 2008, 112-122)'
_computing_structure_refinement
'SHELXL (Sheldrick, Acta Cryst. A64 2008, 112-122)'
_computing_structure_solution
'SHELXS (Sheldrick, Acta Cryst. A64 2008, 112-122)'
_diffrn_ambient_temperature      173(2)
_diffrn_detector_area_resol_mean 836.6
_diffrn_measured_fraction_theta_full 0.984
_diffrn_measured_fraction_theta_max 0.984
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\w,and/f 0.5 deg'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0247
_diffrn_reflns_av_sigmaI/netI    0.0185
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       30
_diffrn_reflns_limit_k_min       -30
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            13497
_diffrn_reflns_theta_full        67.74
_diffrn_reflns_theta_max         67.74
_diffrn_reflns_theta_min         3.51
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    0.728
_exptl_absorpt_correction_T_max  0.9604
_exptl_absorpt_correction_T_min  0.8826
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.351
_exptl_crystal_description       chunk
_exptl_crystal_F_000             624
_exptl_crystal_recrystallization_method CH2Cl2/Hexanes
_exptl_crystal_size_max          0.18
_exptl_crystal_size_mid          0.17
_exptl_crystal_size_min          0.06
_refine_diff_density_max         0.296
_refine_diff_density_min         -0.201
_refine_diff_density_rms         0.037
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.067
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     201
_refine_ls_number_reflns         2580
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.067
_refine_ls_R_factor_all          0.0402
_refine_ls_R_factor_gt           0.0369
_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^)+(0.0446P)^2^+0.6169P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0957
_refine_ls_wR_factor_ref         0.0983
_reflns_number_gt                2375
_reflns_number_total             2580
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo301232w_si_002.cif
_cod_data_source_block           pj312
_cod_original_cell_volume        1446.79(3)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               4027456
_contact_crystallographer_name   'Richard Staples'
_contact_crystallographer_email  staples@chemistry.msu.com