Ring contraction during the 6π-electrocyclisation of naphthopyran valence tautomers
Gabbutt, Christopher D.; Heron, B. Mark; Kolla, Suresh B.; Kilner, Colin; Coles, Simon J.; Horton, Peter N.; Hursthouse, Michael B.; Organic & Biomolecular Chemistry 6 (2008) 3096–3104; doi:10.1039/b807744d

data_7150970
_publ_section_title
;
 Ring contraction during the 6\p-electrocyclisation of naphthopyran
 valence tautomers
;
_journal_issue                   17
_journal_name_full               'Organic &amp; Biomolecular Chemistry'
_journal_page_first              3096
_journal_page_last               3104
_journal_paper_doi               10.1039/b807744d
_journal_volume                  6
_journal_year                    2008
_chemical_formula_sum            'C25 H16 O2 S'
_chemical_formula_weight         380.44
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 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                 101.498(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   11.1939(5)
_cell_length_b                   14.0344(4)
_cell_length_c                   11.7187(5)
_cell_measurement_reflns_used    4256
_cell_measurement_temperature    120(2)
_cell_measurement_theta_max      27.485
_cell_measurement_theta_min      2.910
_cell_volume                     1804.06(12)
_computing_cell_refinement
'DENZO (Otwinowski & Minor, 1997) & COLLECT (Hooft, R.W.W., 1998)'
_computing_data_collection       'COLLECT (Hooft, R.W.W., 1998)'
_computing_data_reduction
'DENZO (Otwinowski & Minor, 1997) & COLLECT (Hooft, R.W.W., 1998)'
_computing_molecular_graphics    'ORTEP3 for Windows (Farrugia, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997b)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997a)'
_diffrn_ambient_temperature      120(2)
_diffrn_detector_area_resol_mean 9.091
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Bruker-Nonius 95mm CCD camera on \k-goniostat'
_diffrn_measurement_method       '\f & \w scans'
_diffrn_radiation_monochromator  '10cm confocal mirrors'
_diffrn_radiation_source         'Bruker-Nonius FR591 rotating anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0999
_diffrn_reflns_av_sigmaI/netI    0.0894
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            21913
_diffrn_reflns_theta_full        27.48
_diffrn_reflns_theta_max         27.48
_diffrn_reflns_theta_min         3.16
_exptl_absorpt_coefficient_mu    0.198
_exptl_absorpt_correction_T_max  0.9921
_exptl_absorpt_correction_T_min  0.9843
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS V2.10 (Sheldrick, G.M., 2003)'
_exptl_crystal_colour            Colourless
_exptl_crystal_density_diffrn    1.401
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Shard
_exptl_crystal_F_000             792
_exptl_crystal_size_max          0.08
_exptl_crystal_size_mid          0.07
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.369
_refine_diff_density_min         -0.361
_refine_diff_density_rms         0.066
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.065
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     253
_refine_ls_number_reflns         4135
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.065
_refine_ls_R_factor_all          0.1094
_refine_ls_R_factor_gt           0.0671
_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^)+(0.0291P)^2^+1.8406P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1124
_refine_ls_wR_factor_ref         0.1255
_reflns_number_gt                2928
_reflns_number_total             4135
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b807744d.txt
_cod_data_source_block           2006src0408
_cod_original_sg_symbol_H-M      P2(1)/n
_cod_database_code               7150970