Protecting-Group-Free Syntheses of <i>ent</i>-Kaurane Diterpenoids: [3+2+1] Cycloaddition/Cycloalkenylation Approach.
Wang, Jin; Hong, Benke; Hu, Dachao; Kadonaga, Yuichiro; Tang, Ruyao; Lei, Xiaoguang; Journal of the American Chemical Society  (2020) –; doi:10.1021/jacs.9b13722

data_4134078
_publ_section_title
;
 Protecting-Group-Free Syntheses of <i>ent</i>-Kaurane Diterpenoids:
 [3+2+1] Cycloaddition/Cycloalkenylation Approach.
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_paper_doi               10.1021/jacs.9b13722
_journal_year                    2020
_chemical_formula_sum            'C20 H26 O2'
_chemical_formula_weight         298.41
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                90
_cell_angle_beta                 93.652(2)
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   20.5218(4)
_cell_length_b                   11.9368(2)
_cell_length_c                   13.4260(2)
_cell_measurement_reflns_used    5856
_cell_measurement_temperature    180.01(10)
_cell_measurement_theta_max      74.8580
_cell_measurement_theta_min      3.3090
_cell_volume                     3282.22(10)
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_diffrn_ambient_environment      N~2~
_diffrn_ambient_temperature      180.01(10)
_diffrn_detector                 'CCD plate'
_diffrn_detector_area_resol_mean 10.3914
_diffrn_detector_type            Atlas
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.971
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'SuperNova, Dual, Cu at home/near, Atlas'
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0217
_diffrn_reflns_av_unetI/netI     0.0293
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.971
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -25
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            12645
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.971
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         74.936
_diffrn_reflns_theta_min         4.287
_diffrn_source                   'micro-focus sealed X-ray tube'
_diffrn_source_type              'SuperNova (Cu) X-ray Source'
_exptl_absorpt_coefficient_mu    0.591
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.84140
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.39.29a (Rigaku Oxford Diffraction, 2015)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.208
_exptl_crystal_description       block
_exptl_crystal_F_000             1296
_exptl_crystal_size_max          0.45
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.18
_refine_diff_density_max         0.705
_refine_diff_density_min         -0.374
_refine_diff_density_rms         0.052
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.045
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     405
_refine_ls_number_reflns         6561
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.045
_refine_ls_R_factor_all          0.0647
_refine_ls_R_factor_gt           0.0556
_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^)+(0.0735P)^2^+2.4010P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1521
_refine_ls_wR_factor_ref         0.1594
_reflns_Friedel_coverage         0.000
_reflns_number_gt                5521
_reflns_number_total             6561
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja9b13722_si_005.cif
_cod_data_source_block           3
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               4134078
_shelx_shelxl_version_number     2014/7
_shelx_res_checksum              10031
_shelx_hkl_checksum              7021