Chromane helicity rule - scope and challenges based on an ECD study of various trolox derivatives.
Górecki, Marcin; Suszczyńska, Agata; Woźnica, Magdalena; Baj, Aneta; Wolniak, Michał; Cyrański, Michał K; Witkowski, Stanisław; Frelek, Jadwiga; Organic & biomolecular chemistry 12 (2014) 2235–2254; doi:10.1039/c3ob42376j

data_7153698
_publ_section_title
;
 Chromane helicity rule - scope and challenges based on an ECD study of
 various trolox derivatives.
;
_journal_issue                   14
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              2235
_journal_page_last               2254
_journal_paper_doi               10.1039/c3ob42376j
_journal_volume                  12
_journal_year                    2014
_chemical_absolute_configuration syn
_chemical_formula_sum            'C15 H20 O4'
_chemical_formula_weight         264.31
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_atom_sites_solution_hydrogens   geom
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_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
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_cell_angle_beta                 97.085(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.1858(3)
_cell_length_b                   21.2747(8)
_cell_length_c                   8.7923(4)
_cell_measurement_reflns_used    6531
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      28.6937
_cell_measurement_theta_min      1.9106
_cell_volume                     1333.87(10)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 8.4441
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Xcalibur, Opal'
_diffrn_measurement_method       'omega scan'
_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  0.0359
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_diffrn_reflns_limit_h_min       -8
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_diffrn_reflns_limit_l_min       -10
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_diffrn_standards_number         '1 frame'
_exptl_absorpt_coefficient_mu    0.094
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.86102
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro, Agilent Technologies,
Version 1.171.36.20 (release 27-06-2012 CrysAlis171 .NET)
(compiled Jul 11 2012,15:38:31)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            Colorless
_exptl_crystal_density_diffrn    1.316
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Prism
_exptl_crystal_F_000             568
_exptl_crystal_size_max          0.15
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_exptl_crystal_size_min          0.11
_refine_diff_density_max         0.415
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_refine_ls_extinction_method     none
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_refine_ls_matrix_type           full
_refine_ls_number_parameters     361
_refine_ls_number_reflns         2429
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.120
_refine_ls_R_factor_all          0.0504
_refine_ls_R_factor_gt           0.0458
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0710P)^2^+0.5856P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1211
_refine_ls_wR_factor_ref         0.1246
_reflns_number_gt                2251
_reflns_number_total             2429
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c3ob42376j2.cif
_cod_data_source_block           compound1
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to
/usr/data/users/saulius/crontab/automatic-downloads/current/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 2281 2013-09-26 08:29:07Z andrius 
;
_cod_original_sg_symbol_Hall     P2yb
_cod_original_sg_symbol_H-M      P2(1)
_cod_database_code               7153698