Synthetic and mechanistic study of the acid-promoted aromatisation of the Diels–Alder adduct: 6,7-dimethoxy-1-(4-pyridyl)-1,4-epoxytetrahydronaphthalene-2,3-dicarboxylate
Sugahara, Masakatsu; Moritani, Yasunori; Kuroda, Tooru; Kondo, Kazuhiko; Ukita, Tatsuzo; Journal of the Chemical Society, Perkin Transactions 1  (2002) 768–; doi:10.1039/b110265f

data_7204318
_publ_section_title
;
 Synthetic and mechanistic study of the acid-promoted aromatisation of
 the Diels--Alder adduct:
 6,7-dimethoxy-1-(4-pyridyl)-1,4-epoxytetrahydronaphthalene-2,3-dicarboxylate
;
_journal_issue                   6
_journal_name_full
'Journal of the Chemical Society, Perkin Transactions 1'
_journal_page_first              768
_journal_paper_doi               10.1039/b110265f
_journal_year                    2002
_chemical_formula_sum            'C21 H21 N O7'
_chemical_formula_weight         399.39
_chemical_name_systematic
; 
1,4-Epoxynaphthalene-2,3-dicarboxylic acid, 1-(4-pyridyl)-
1,2,3,4-tetrahydro-6,7-dimethoxy-, dimethyl ester, (1beta, 2alpha ,
3alpha , 4beta)-rel- (9CI)
;
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/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                 98.73(1)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   34.619(2)
_cell_length_b                   6.874(2)
_cell_length_c                   16.426(2)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293
_cell_measurement_theta_max      45
_cell_measurement_theta_min      35
_cell_volume                     3863.6(12)
_computing_cell_refinement       'Rigaku/MSC AFC5R software 1992'
_computing_data_collection       'Rigaku/MSC AFC5R software 1992'
_computing_data_reduction        'Rigaku/MSC AFC5R software 1992'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Rigaku AFC5R diffractometer'
_diffrn_measurement_method       ot
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'nomal-focus rotating anode'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0103
_diffrn_reflns_av_sigmaI/netI    0.0112
_diffrn_reflns_limit_h_max       40
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            3345
_diffrn_reflns_theta_full        65.07
_diffrn_reflns_theta_max         65.07
_diffrn_reflns_theta_min         2.58
_diffrn_standards_decay_%        0.0
_diffrn_standards_interval_count 200
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.870
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.373
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             1680
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.3
_exptl_crystal_size_min          0.3
_refine_diff_density_max         0.339
_refine_diff_density_min         -0.377
_refine_diff_density_rms         0.046
_refine_ls_extinction_coef       0.0021(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   1.539
_refine_ls_hydrogen_treatment    noref
_refine_ls_matrix_type           full
_refine_ls_number_parameters     263
_refine_ls_number_reflns         3288
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.539
_refine_ls_R_factor_all          0.0492
_refine_ls_R_factor_gt           0.0448
_refine_ls_shift/su_max          0.017
_refine_ls_shift/su_mean         0.003
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1740
_refine_ls_wR_factor_ref         0.1788
_reflns_number_gt                2972
_reflns_number_total             3288
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b110265f.txt
_cod_data_source_block           compound2
_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 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 
;
_cod_original_cell_volume        3863.7(10)
_cod_original_sg_symbol_H-M      C2/c
_cod_database_code               7204318