Development of a Unified Enantioselective, Convergent Synthetic Approach Toward the Furanobutenolide-Derived Polycyclic Norcembranoid Diterpenes: Asymmetric Formation of the Polycyclic Norditerpenoid Carbocyclic Core by Tandem Annulation Cascade.
Craig, 2nd, Robert A; Smith, Russell C.; Roizen, Jennifer L.; Jones, Amanda C.; Virgil, Scott C.; Stoltz, Brian M.; The Journal of organic chemistry 83 (2018) 3467–3485; doi:10.1021/acs.joc.7b02825

data_4033552
_publ_section_title
;
 Development of a Unified Enantioselective, Convergent Synthetic Approach
 Toward the Furanobutenolide-Derived Polycyclic Norcembranoid Diterpenes:
 Asymmetric Formation of the Polycyclic Norditerpenoid Carbocyclic Core by
 Tandem Annulation Cascade.
;
_journal_issue                   7
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              3467
_journal_page_last               3485
_journal_paper_doi               10.1021/acs.joc.7b02825
_journal_volume                  83
_journal_year                    2018
_chemical_absolute_configuration ad
_chemical_formula_sum            'C19 H23 Br O5'
_chemical_formula_weight         411.28
_space_group_crystal_system      orthorhombic
_space_group_IT_number           19
_space_group_name_Hall           'P 2ac 2ab'
_space_group_name_H-M_alt        'P 21 21 21'
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   7.6137(4)
_cell_length_b                   9.3584(5)
_cell_length_c                   24.1592(13)
_cell_measurement_reflns_used    9810
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      37.12
_cell_measurement_theta_min      2.75
_cell_volume                     1721.39(16)
_computing_cell_refinement       'SAINT v8.34A (Bruker-AXS, 2013)'
_computing_data_collection       'APEX2 v2014.9-0 (Bruker-AXS, 2014)'
_computing_data_reduction        'SAINT v8.34A (Bruker-AXS, 2013)'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXS-2013/1 (Sheldrick, 2013)'
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 8.33
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Bruker KAPPA APEXII CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0380
_diffrn_reflns_av_unetI/netI     0.0388
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.996
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       40
_diffrn_reflns_limit_l_min       -39
_diffrn_reflns_number            51998
_diffrn_reflns_point_group_measured_fraction_full 0.991
_diffrn_reflns_point_group_measured_fraction_max 0.991
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         36.318
_diffrn_reflns_theta_min         2.334
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    2.416
_exptl_absorpt_correction_T_max  0.7478
_exptl_absorpt_correction_T_min  0.5973
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS-2014/4 (Sheldrick, 2014)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.587
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Block
_exptl_crystal_F_000             848
_exptl_crystal_size_max          0.500
_exptl_crystal_size_mid          0.450
_exptl_crystal_size_min          0.100
_refine_diff_density_max         0.746
_refine_diff_density_min         -0.367
_refine_diff_density_rms         0.066
_refine_ls_abs_structure_details
; 
 Flack x determined using 3023 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259). 
;
_refine_ls_abs_structure_Flack   0.014(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.035
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     231
_refine_ls_number_reflns         8272
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.035
_refine_ls_R_factor_all          0.0297
_refine_ls_R_factor_gt           0.0251
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0289P)^2^+0.0363P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0613
_refine_ls_wR_factor_ref         0.0625
_reflns_Friedel_coverage         0.775
_reflns_Friedel_fraction_full    0.980
_reflns_Friedel_fraction_max     0.986
_reflns_number_gt                7574
_reflns_number_total             8272
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            jo7b02825_si_006.cif
_cod_data_source_block           rac10
_cod_depositor_comments
'Adding full bibliography for 4033550--4033552.cif.'
_cod_database_code               4033552
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.378
_shelx_estimated_absorpt_t_max   0.794
_shelx_res_checksum              34537
_shelx_hkl_checksum              44040