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_7150969
_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_moiety         'C25 H16 O2 S'
_chemical_formula_sum            'C25 H16 O2 S'
_chemical_formula_weight         380.44
_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                 99.926(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   19.3719(8)
_cell_length_b                   11.5100(5)
_cell_length_c                   16.4409(6)
_cell_measurement_reflns_used    8165
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      28.16
_cell_measurement_theta_min      2.51
_cell_volume                     3611.0(3)
_computing_cell_refinement
;
APEX 2 software, Bruker Nonius 2004
;
_computing_data_collection
;
APEX 2 software, Bruker Nonius 2004
;
_computing_data_reduction
;
SAINT - Bruker Integration program embedded in
APEX 2 software, Bruker Nonius 2004
;
_computing_molecular_graphics    'ORTEP-III Version 1.08 (Farrugia, 2005)'
_computing_publication_material
;
enCIFer: A program for viewing, editing and visualising CIFs.
F. H. Allen, O. Johnson, G. P. Shields, B. R. Smith, M. Towler,
J. Applied Cryst., 37, 331-334, 2004
;
_computing_structure_refinement
;
SHELXL-97 (Sheldrick, 1997)
XSeed (L.J.Barbour, J.Supramol. Chem., 2003, 1, 189.)
;
_computing_structure_solution
;
SHELXS-97 (Sheldrick, 1990)
XSeed (L.J.Barbour, J.Supramol. Chem., 2003, 1, 189.)
;
_diffrn_detector_area_resol_mean
;
120 microns
;
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type
;
Mach3 kappa-type 4-circle goniostat.
;
_diffrn_measurement_method       'rotation images'
_diffrn_radiation_detector       'ApexII camera'
_diffrn_radiation_monochromator
;
graphite model mounted in "parallel" mode
;
_diffrn_radiation_source
;
Bruker Nonius FR591 rotating anode generator
;
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0437
_diffrn_reflns_av_sigmaI/netI    0.0300
_diffrn_reflns_limit_h_max       25
_diffrn_reflns_limit_h_min       -25
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            29976
_diffrn_reflns_theta_full        28.30
_diffrn_reflns_theta_max         28.30
_diffrn_reflns_theta_min         2.32
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.198
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            'pale brown'
_exptl_crystal_density_diffrn    1.400
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       fragment
_exptl_crystal_F_000             1584
_exptl_crystal_size_max          0.29
_exptl_crystal_size_mid          0.26
_exptl_crystal_size_min          0.21
_refine_diff_density_max         0.309
_refine_diff_density_min         -0.541
_refine_diff_density_rms         0.049
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.025
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     253
_refine_ls_number_reflns         4465
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.025
_refine_ls_R_factor_all          0.0486
_refine_ls_R_factor_gt           0.0370
_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^)+(0.0389P)^2^+3.4008P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0875
_refine_ls_wR_factor_ref         0.0936
_reflns_number_gt                3671
_reflns_number_total             4465
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b807744d.txt
_cod_data_source_block           sk-1-64
_cod_original_sg_symbol_H-M      C2/c
_cod_database_code               7150969