A hydrogen peroxide based access to qinghaosu (artemisinin).
Hao, Hong-Dong; Li, Yun; Han, Wei-Bo; Wu, Yikang; Organic letters 13 (2011) 4212–4215; doi:10.1021/ol2015434

data_1502322
_publ_section_title
;
 A hydrogen peroxide based access to qinghaosu (artemisinin).
;
_journal_issue                   16
_journal_name_full               'Organic letters'
_journal_page_first              4212
_journal_page_last               4215
_journal_paper_doi               10.1021/ol2015434
_journal_volume                  13
_journal_year                    2011
_chemical_absolute_configuration ad
_chemical_formula_sum            'C15 H22 O4'
_chemical_formula_weight         266.33
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   9.0867(18)
_cell_length_b                   12.110(2)
_cell_length_c                   13.383(3)
_cell_measurement_reflns_used    2793
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      45.744
_cell_measurement_theta_min      4.536
_cell_volume                     1472.7(5)
_computing_cell_refinement       'Bruker XSCANS'
_computing_data_collection       'Bruker XSCANS'
_computing_data_reduction        'Bruker SHELXTL'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Bruker P4'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0272
_diffrn_reflns_av_sigmaI/netI    0.0307
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            8047
_diffrn_reflns_theta_full        26.00
_diffrn_reflns_theta_max         26.00
_diffrn_reflns_theta_min         2.27
_exptl_absorpt_coefficient_mu    0.086
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.60600
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.201
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             576
_exptl_crystal_size_max          0.347
_exptl_crystal_size_mid          0.195
_exptl_crystal_size_min          0.173
_refine_diff_density_max         0.152
_refine_diff_density_min         -0.160
_refine_diff_density_rms         0.043
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.5(13)
_refine_ls_extinction_coef       0.127(7)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.056
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     176
_refine_ls_number_reflns         2861
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.056
_refine_ls_R_factor_all          0.0489
_refine_ls_R_factor_gt           0.0432
_refine_ls_shift/su_max          0.005
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0606P)^2^+0.0924P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1077
_refine_ls_wR_factor_ref         0.1119
_reflns_number_gt                2514
_reflns_number_total             2861
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol2015434_si_003.cif
_cod_data_source_block           cd21156
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_cell_volume        1472.6(5)
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               1502322