Unexpected regioselectivity in the synthesis of pyranonaphthoquinone via the Diels-Alder reaction.
Cui, Yi; Jiang, Hao; Li, Zhengtao; Wu, Na; Yang, Zhen; Quan, Junmin; Organic letters 11 (2009) 4628–4631; doi:10.1021/ol901902v

data_1504195
_publ_section_title
;
 Unexpected regioselectivity in the synthesis of pyranonaphthoquinone via
 the Diels-Alder reaction.
;
_journal_issue                   20
_journal_name_full               'Organic letters'
_journal_page_first              4628
_journal_page_last               4631
_journal_paper_doi               10.1021/ol901902v
_journal_volume                  11
_journal_year                    2009
_chemical_formula_moiety         'C18 H13 F3 O9 S'
_chemical_formula_sum            'C18 H13 F3 O9 S'
_chemical_formula_weight         462.34
_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   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 92.316(16)
_cell_angle_gamma                90.00
_cell_formula_units_Z            16
_cell_length_a                   18.964(5)
_cell_length_b                   13.633(3)
_cell_length_c                   29.823(6)
_cell_measurement_reflns_used    35
_cell_measurement_temperature    295(2)
_cell_measurement_theta_max      12.50
_cell_measurement_theta_min      2.12
_cell_volume                     7704(3)
_computing_cell_refinement       'XSCANS (Bruker, 1997)'
_computing_data_collection       'XSCANS (Bruker, 1997)'
_computing_data_reduction        'XSCANS (Bruker, 1997)'
_computing_molecular_graphics    'SHELXTL (Bruker, 1997)'
_computing_publication_material  'SHELXTL (Bruker, 1997)'
_computing_structure_refinement  'SHELXTL (Bruker, 1997)'
_computing_structure_solution    'SHELXTL (Bruker, 1997)'
_diffrn_ambient_temperature      295(2)
_diffrn_measured_fraction_theta_full 0.988
_diffrn_measured_fraction_theta_max 0.988
_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  0.0466
_diffrn_reflns_av_sigmaI/netI    0.1136
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -1
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -1
_diffrn_reflns_limit_l_max       35
_diffrn_reflns_limit_l_min       -35
_diffrn_reflns_number            16043
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.95
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 97
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.248
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.594
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             3776
_exptl_crystal_size_max          0.5
_exptl_crystal_size_mid          0.3
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.872
_refine_diff_density_min         -0.644
_refine_diff_density_rms         0.068
_refine_ls_extinction_coef       0.00027(3)
_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   1.211
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     1118
_refine_ls_number_reflns         13410
_refine_ls_number_restraints     27
_refine_ls_restrained_S_all      1.286
_refine_ls_R_factor_all          0.2491
_refine_ls_R_factor_gt           0.0895
_refine_ls_shift/su_max          0.016
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.001P)^2^+8.0P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1604
_refine_ls_wR_factor_ref         0.2147
_reflns_number_gt                3478
_reflns_number_total             13410
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ol901902v_si_001.cif
_cod_data_source_block           yangz-5
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               1504195