Indium triflate-catalysed Diels-Alder reactions of isochromenylium cations with enones.
Selvi, Thangavel; Srinivasan, Kannupal; Organic & biomolecular chemistry 11 (2013) 2162–2167; doi:10.1039/c3ob26284g

data_7152848
_publ_section_title
;
 Indium triflate-catalysed Diels-Alder reactions of isochromenylium
 cations with enones.
;
_journal_issue                   13
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              2162
_journal_page_last               2167
_journal_paper_doi               10.1039/c3ob26284g
_journal_volume                  11
_journal_year                    2013
_chemical_formula_moiety         'C33 H28 O4'
_chemical_formula_sum            'C33 H28 O4'
_chemical_formula_weight         488.55
_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                 98.9390(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   13.3763(2)
_cell_length_b                   18.3674(2)
_cell_length_c                   10.67070(10)
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      20.53
_cell_measurement_theta_min      1.54
_cell_volume                     2589.82(5)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_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  0.0355
_diffrn_reflns_av_sigmaI/netI    0.0163
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            32650
_diffrn_reflns_theta_full        20.53
_diffrn_reflns_theta_max         20.53
_diffrn_reflns_theta_min         1.54
_exptl_absorpt_coefficient_mu    0.081
_exptl_absorpt_correction_T_max  0.9823
_exptl_absorpt_correction_T_min  0.9635
_exptl_crystal_colour            brown
_exptl_crystal_density_diffrn    1.253
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Needle
_exptl_crystal_F_000             1032
_exptl_crystal_size_max          0.46
_exptl_crystal_size_mid          0.22
_exptl_crystal_size_min          0.22
_refine_diff_density_max         0.304
_refine_diff_density_min         -0.170
_refine_diff_density_rms         0.030
_refine_ls_extinction_coef       0.0035(11)
_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   1.031
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     359
_refine_ls_number_reflns         2600
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.031
_refine_ls_R_factor_all          0.0513
_refine_ls_R_factor_gt           0.0419
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0639P)^2^+1.2650P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1112
_refine_ls_wR_factor_ref         0.1199
_reflns_number_gt                2160
_reflns_number_total             2600
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c3ob26284g.txt
_cod_data_source_block           shelxl
_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 1891 2012-01-12 08:04:46Z andrius 
;
_cod_original_sg_symbol_H-M      P21/c
_cod_database_code               7152848