Exo/endo selectivity-control in Lewis-acid catalyzed tandem heterocyclization/formal [4+3] cycloaddition: synthesis of polyheterocycles from 2-(1-alkynyl)-2-alken-1-ones and 1,3-diphenylisobenzofuran
Hongyin Gao; Xingxing Wu; Junliang Zhang; Chem.Commun. 46 (2010) 8764–; doi:10.1039/c0cc02778b

data_7105671
_publ_section_title
;
 Exo/endo selectivity-control in Lewis-acid catalyzed tandem
 heterocyclization/formal [4+3] cycloaddition: synthesis of
 polyheterocycles from 2-(1-alkynyl)-2-alken-1-ones and
 1,3-diphenylisobenzofuran
;
_journal_name_full               Chem.Commun.
_journal_page_first              8764
_journal_paper_doi               10.1039/c0cc02778b
_journal_volume                  46
_journal_year                    2010
_chemical_formula_sum            'C38 H28 O2'
_chemical_formula_weight         516.60
_space_group_IT_number           29
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2ac'
_symmetry_space_group_name_H-M   'P c a 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                   16.4516(5)
_cell_length_b                   10.4221(3)
_cell_length_c                   15.5783(5)
_cell_measurement_temperature    173(2)
_cell_volume                     2671.06(14)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_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  0.0198
_diffrn_reflns_av_sigmaI/netI    0.0127
_diffrn_reflns_limit_h_max       19
_diffrn_reflns_limit_h_min       -19
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            29372
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         2.31
_exptl_absorpt_coefficient_mu    0.078
_exptl_absorpt_correction_T_max  1
_exptl_absorpt_correction_T_min  0.868250
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.285
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1088
_exptl_crystal_size_max          0.448
_exptl_crystal_size_mid          0.257
_exptl_crystal_size_min          0.236
_refine_diff_density_max         0.165
_refine_diff_density_min         -0.143
_refine_diff_density_rms         0.028
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   1.2(8)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.046
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     361
_refine_ls_number_reflns         4698
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.046
_refine_ls_R_factor_all          0.0272
_refine_ls_R_factor_gt           0.0265
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0426P)^2^+0.4455P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0701
_refine_ls_wR_factor_ref         0.0708
_reflns_number_gt                4603
_reflns_number_total             4698
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            C0CC02778B.TXT
_cod_data_source_block           z_4a
_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_enum 1527 2010-12-29 10:47:43Z saulius 
;
_cod_original_sg_symbol_H-M      Pca2(1)
_cod_database_code               7105671