Controlling ring-chain tautomerism through steric hindrance
García-Deibe, Ana M.; Portela-García, Cristina; Fondo, Matilde; Sanmartin, Jesus; RSC Adv.  (2015) –; doi:10.1039/C5RA10132H

data_7220925
_publ_section_title
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 Controlling ring-chain tautomerism through steric hindrance
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_journal_name_full               'RSC Adv.'
_journal_paper_doi               10.1039/C5RA10132H
_journal_year                    2015
_chemical_formula_moiety         'C21 H20 N2 O4 S'
_chemical_formula_sum            'C21 H20 N2 O4 S'
_chemical_formula_weight         396.45
_chemical_properties_physical    Thermocromic
_space_group_crystal_system      triclinic
_space_group_IT_number           2
_space_group_name_Hall           '-P 1'
_space_group_name_H-M_alt        'P -1'
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   mixed
_audit_creation_method           SHELXL-2013
_audit_update_record
;
2015-05-22 deposited with the CCDC.
2015-06-26 downloaded from the CCDC.
;
_cell_angle_alpha                68.918(5)
_cell_angle_beta                 67.153(4)
_cell_angle_gamma                88.425(6)
_cell_formula_units_Z            2
_cell_length_a                   8.979(4)
_cell_length_b                   10.358(5)
_cell_length_c                   12.109(6)
_cell_measurement_reflns_used    24
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      42.53
_cell_measurement_theta_min      22.85
_cell_volume                     960.1(8)
_computing_cell_refinement       'CAD4 Express (Enraf Nonius, 1994)'
_computing_data_collection       'CAD4 Express (Enraf Nonius, 1994)'
_computing_data_reduction        'XCAD4 (Harms & Wocadlo, 1995)'
_computing_structure_refinement  'SHELXL-2013 (Sheldrick, 2013)'
_computing_structure_solution    'SHELXS-2013 (Sheldrick, 2013)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Enraf Nonius TurboCAD4'
_diffrn_measurement_method       'non-profiled omega/2theta scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0168
_diffrn_reflns_av_unetI/netI     0.0187
_diffrn_reflns_Laue_measured_fraction_full 0.998
_diffrn_reflns_Laue_measured_fraction_max 0.997
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            4133
_diffrn_reflns_point_group_measured_fraction_full 0.998
_diffrn_reflns_point_group_measured_fraction_max 0.997
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         74.082
_diffrn_reflns_theta_min         4.281
_diffrn_source                   'Enraf Nonius FR590'
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  120
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    1.757
_exptl_absorpt_correction_T_max  0.8183
_exptl_absorpt_correction_T_min  0.6965
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details
;
North A.C.T., Phillips D.C. & Mathews F.S. (1968) Acta. Cryst. A24, 351
Number of psi-scan sets used was   7
Theta correction was applied.
Weighted transmission curves were used.
No Fourier smoothing was applied.
;
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    1.371
_exptl_crystal_description       prism
_exptl_crystal_F_000             416
_exptl_crystal_size_max          0.39
_exptl_crystal_size_mid          0.28
_exptl_crystal_size_min          0.11
_refine_diff_density_max         0.400
_refine_diff_density_min         -0.296
_refine_diff_density_rms         0.058
_refine_ls_extinction_coef       0.0053(8)
_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   1.068
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     272
_refine_ls_number_reflns         3877
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.068
_refine_ls_R_factor_all          0.0594
_refine_ls_R_factor_gt           0.0459
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0849P)^2^+0.1293P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1280
_refine_ls_wR_factor_ref         0.1375
_reflns_Friedel_coverage         0.000
_reflns_number_gt                3207
_reflns_number_total             3877
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c5ra10132h2.cif
_cod_data_source_block           shelx
_cod_database_code               7220925
_shelx_estimated_absorpt_t_min   0.547
_shelx_estimated_absorpt_t_max   0.830
_shelxl_version_number           2013-4
_shelx_res_checksum              84686