Dyotropic Rearrangements of Fused Tricyclic β-Lactones: Application to the Synthesis of (-)-Curcumanolide A and (-)-Curcumalactone
Carolyn A. Leverett; Vikram C. Purohit; Alex G. Johnson; Rebecca L. Davis; Dean J. Tantillo; Daniel Romo; Journal of the American Chemical Society 134 (2012) 13348–13356; doi:10.1021/ja303414a

data_4118498
_publ_section_title
;
 Dyotropic Rearrangements of Fused Tricyclic \b-Lactones: Application to
 the Synthesis of (-)-Curcumanolide A and (-)-Curcumalactone
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              13348
_journal_page_last               13356
_journal_paper_doi               10.1021/ja303414a
_journal_volume                  134
_journal_year                    2012
_chemical_absolute_configuration ab
_chemical_formula_sum            'C17 H16 Br N O4'
_chemical_formula_weight         378.22
_space_group_IT_number           5
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'C 2y'
_symmetry_space_group_name_H-M   'C 1 2 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                 95.433(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   19.8802(12)
_cell_length_b                   6.2307(4)
_cell_length_c                   12.7748(8)
_cell_measurement_reflns_used    7725
_cell_measurement_temperature    110(2)
_cell_measurement_theta_max      62.84
_cell_measurement_theta_min      3.48
_cell_volume                     1575.27(17)
_computing_cell_refinement       'Bruker FRAMBO'
_computing_data_collection       'Bruker FRAMBO'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      110(2)
_diffrn_measured_fraction_theta_full 0.987
_diffrn_measured_fraction_theta_max 0.987
_diffrn_measurement_device_type  'MWPC area detector'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0539
_diffrn_reflns_av_sigmaI/netI    0.0335
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -22
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            11556
_diffrn_reflns_theta_full        59.98
_diffrn_reflns_theta_max         59.98
_diffrn_reflns_theta_min         3.48
_exptl_absorpt_coefficient_mu    3.740
_exptl_absorpt_correction_T_max  0.8067
_exptl_absorpt_correction_T_min  0.4000
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            'colorless '
_exptl_crystal_density_diffrn    1.595
_exptl_crystal_description       'needle     '
_exptl_crystal_F_000             768
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.06
_exptl_crystal_size_min          0.06
_refine_diff_density_max         0.380
_refine_diff_density_min         -0.595
_refine_diff_density_rms         0.070
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.028(19)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.009
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     209
_refine_ls_number_reflns         2225
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.008
_refine_ls_R_factor_all          0.0316
_refine_ls_R_factor_gt           0.0302
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0570P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0740
_refine_ls_wR_factor_ref         0.0747
_reflns_number_gt                2119
_reflns_number_total             2225
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja303414a_si_002.cif
_cod_data_source_block           dr79
_cod_database_code               4118498