Novel stereoconvergent transformation of 1,2a-disubstituted 1,2,2a,8b-tetrahydro-3H-benzo[b]cyclobuta[d]pyran-3-ones to 1,3-disubstituted 1,2,4a,9b-tetrahydrodibenzofuran-4-ols and its application to the second-generation synthesis of (+/-)-linderol A.
Yamashita, Masayuki; Inaba, Tomoki; Nagahama, Masaki; Shimizu, Takashi; Kosaka, Sachiko; Kawasaki, Ikuo; Ohta, Shunsaku; Organic & biomolecular chemistry 3 (2005) 2296–2304; doi:10.1039/b503890a

data_7150167
_publ_section_title
;
 Novel stereoconvergent transformation of 1,2a-disubstituted
 1,2,2a,8b-tetrahydro-3H-benzo[b]cyclobuta[d]pyran-3-ones to
 1,3-disubstituted 1,2,4a,9b-tetrahydrodibenzofuran-4-ols and its
 application to the second-generation synthesis of (+/-)-linderol A.
;
_journal_issue                   12
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              2296
_journal_page_last               2304
_journal_paper_doi               10.1039/b503890a
_journal_volume                  3
_journal_year                    2005
_chemical_formula_moiety         'C21 H20 O4 '
_chemical_formula_sum            'C21 H20 O4'
_chemical_formula_weight         336.39
_space_group_IT_number           61
_symmetry_cell_setting           orthorhombic
_symmetry_Int_Tables_number      61
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   22.3809(9)
_cell_length_b                   17.2516(8)
_cell_length_c                   9.034(1)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    296.2
_cell_measurement_theta_max      30.0
_cell_measurement_theta_min      29.5
_cell_volume                     3488.1(4)
_computing_cell_refinement       'MSC/AFC Diffractometer Control'
_computing_data_collection       'MSC/AFC Diffractometer Control'
_computing_data_reduction        'teXsan Ver. 2.0'
_computing_publication_material  'teXsan Ver. 2.0'
_computing_structure_refinement  'teXsan Ver. 2.0'
_computing_structure_solution    SAPI91
_diffrn_measured_fraction_theta_full 0.9996
_diffrn_measured_fraction_theta_max 0.9996
_diffrn_measurement_device_type  'Rigaku AFC7R'
_diffrn_measurement_method       \w-2\q
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.5418
_diffrn_reflns_av_R_equivalents  0.011
_diffrn_reflns_limit_h_max       25
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            2982
_diffrn_reflns_theta_full        60.09
_diffrn_reflns_theta_max         60.09
_diffrn_standards_decay_%        1.98
_diffrn_standards_interval_count 150
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.716
_exptl_absorpt_correction_T_max  0.998
_exptl_absorpt_correction_T_min  0.802
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details   '(North, Phillips & Mathews, 1968)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.281
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       column
_exptl_crystal_F_000             1424.00
_exptl_crystal_size_max          0.250
_exptl_crystal_size_mid          0.200
_exptl_crystal_size_min          0.200
_refine_diff_density_max         0.41
_refine_diff_density_min         -0.39
_refine_ls_extinction_coef       0.098(9)
_refine_ls_extinction_method     'Zachariasen(1967) type 2 Gaussian isotropic'
_refine_ls_goodness_of_fit_ref   1.934
_refine_ls_hydrogen_treatment    noref
_refine_ls_number_parameters     227
_refine_ls_number_reflns         2596
_refine_ls_R_factor_gt           0.0575
_refine_ls_shift/su_max          0.0002
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^) + (0.07800(Max(Fo^2^,0) + 2Fc^2^)/3)^2^]'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         0.2055
_reflns_number_gt                2048
_reflns_number_total             2597
_reflns_threshold_expression     F^2^>2.0\s(F^2^)
_cod_data_source_file            b503890a.txt
_cod_data_source_block           1
_cod_original_cell_volume        3488.1(7)
_cod_original_sg_symbol_H-M      'P b c a '
_cod_original_formula_sum        'C21 H20 O4 '
_cod_database_code               7150167