Synthesis of (±)-likonide B (smenochromene D) using a regioselective Claisen rearrangement, separation of the enantiomers and stereochemical assignment
Bruder, Marjorie; Smith, Stephen J.; Blake, Alexander J.; Moody, Christopher J.; Organic & Biomolecular Chemistry 7 (2009) 2127–2134; doi:10.1039/b901358j

data_7150650
_publ_section_title
;
 Synthesis of (+-)-likonide B (smenochromene D) using a regioselective
 Claisen rearrangement, separation of the enantiomers and
 stereochemical assignment
;
_journal_issue                   10
_journal_name_full               'Organic &amp; Biomolecular Chemistry'
_journal_page_first              2127
_journal_page_last               2134
_journal_paper_doi               10.1039/b901358j
_journal_volume                  7
_journal_year                    2009
_chemical_formula_moiety         'C22 H28 O3'
_chemical_formula_sum            'C22 H28 O3'
_chemical_formula_weight         340.44
_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
'sp2-bound methyl H atoms from delta-F; others placed geometrically'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           'enCIFer editing of SHELXL97 CIF output'
_cell_angle_alpha                90.00
_cell_angle_beta                 103.091(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.3277(8)
_cell_length_b                   9.6466(7)
_cell_length_c                   15.9180(11)
_cell_measurement_reflns_used    5150
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      27.4
_cell_measurement_theta_min      2.5
_cell_volume                     1843.8(2)
_computing_cell_refinement       'Bruker SAINT version 6.36A (Bruker, 2000)'
_computing_data_collection       'Bruker SMART version 5.625 (Bruker, 2001)'
_computing_data_reduction        'Bruker SAINT; Bruker SHELXTL (Bruker, 2001)'
_computing_publication_material
'enCIFer (Allen et al., 2004); PLATON (Spek, 2003)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Bruker SMART APEX CCD area detector'
_diffrn_measurement_method       omega
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.069
_diffrn_reflns_av_sigmaI/netI    0.040
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            16435
_diffrn_reflns_theta_full        27.50
_diffrn_reflns_theta_max         27.50
_diffrn_reflns_theta_min         2.49
_diffrn_standards_decay_%        0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.080
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.226
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             736
_exptl_crystal_size_max          0.79
_exptl_crystal_size_mid          0.76
_exptl_crystal_size_min          0.50
_refine_diff_density_max         0.33
_refine_diff_density_min         -0.21
_refine_diff_density_rms         0.05
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.06
_refine_ls_hydrogen_treatment    'rigid rotor; riding model'
_refine_ls_matrix_type           full
_refine_ls_number_parameters     228
_refine_ls_number_reflns         4213
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.06
_refine_ls_R_factor_all          0.0481
_refine_ls_R_factor_gt           0.0436
_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^)+(0.069P)^2^+0.329P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.120
_refine_ls_wR_factor_ref         0.124
_reflns_number_gt                3689
_reflns_number_total             4213
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            b901358j.txt
_cod_data_source_block           bzfude
_cod_original_cell_volume        1843.8(4)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               7150650