Chlorination Increases the Persistence of Semiquinone Free Radicals Derived from Polychlorinated Biphenyl Hydroquinones and Quinones
Yang Song; Garry R. Buettner; Sean Parkin; Brett A. Wagner; Larry W. Robertson; Hans-Joachim Lehmler; Journal of Organic Chemistry 73 (2008) 8296–8304; doi:10.1021/jo801397g

data_4023801
_publ_contact_author_address
;The University of Iowa
Department of Occupational and Environmental Health
100 Oakdale Campus, 124 IREH
Iowa City, IA 52242-5000
USA
;
_publ_contact_author_email       hans-joachim-lehmler@uiowa.edu
_publ_contact_author_fax         '1 (319) 335-4290'
_publ_contact_author_name        'Hans-Joachim Lehmler'
_publ_contact_author_phone       '1 (319) 335-4211'
_publ_section_title
;
 Chlorination Increases the Persistence of Semiquinone Free Radicals
 Derived from Polychlorinated Biphenyl Hydroquinones and Quinones
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              8296
_journal_page_last               8304
_journal_paper_doi               10.1021/jo801397g
_journal_volume                  73
_journal_year                    2008
_chemical_formula_moiety         'C7 H5 Br Cl2 O2'
_chemical_formula_sum            'C7 H5 Br Cl2 O2'
_chemical_formula_weight         271.92
_chemical_name_systematic
; 
2-Bromo-3,6-dichloro-4-methoxy-phenol
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                85.8672(8)
_cell_angle_beta                 75.3724(8)
_cell_angle_gamma                81.0843(8)
_cell_formula_units_Z            4
_cell_length_a                   8.10327(10)
_cell_length_b                   9.2723(2)
_cell_length_c                   12.0905(2)
_cell_measurement_reflns_used    14313
_cell_measurement_temperature    90.0(2)
_cell_measurement_theta_max      27.48
_cell_measurement_theta_min      1.00
_cell_volume                     867.85(3)
_computing_cell_refinement       'SCALEPACK (Otwinowski & Minor, 1997)'
_computing_data_collection       'COLLECT (Nonius, 1998)'
_computing_data_reduction        'DENZO-SMN (Otwinowski & Minor, 1997)'
_computing_molecular_graphics    'XP in SHELXTL (Sheldrick, 2008)'
_computing_publication_material
; 
SHELX97-2 (Sheldrick, 2008) and local procedures 
;
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      90.0(2)
_diffrn_detector_area_resol_mean 18
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Nonius KappaCCD diffractometer'
_diffrn_measurement_method       '\w scans at fixed \c = 55\%'
_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  0.0393
_diffrn_reflns_av_sigmaI/netI    0.0314
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            19069
_diffrn_reflns_theta_full        27.49
_diffrn_reflns_theta_max         27.49
_diffrn_reflns_theta_min         1.74
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    5.303
_exptl_absorpt_correction_T_max  0.588
_exptl_absorpt_correction_T_min  0.160
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Sadabs (Bruker-Nonius, 1997)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    2.081
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       slab
_exptl_crystal_F_000             528
_exptl_crystal_size_max          0.38
_exptl_crystal_size_mid          0.36
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.567
_refine_diff_density_min         -0.484
_refine_diff_density_rms         0.087
_refine_ls_extinction_coef       0.0015(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   1.045
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     222
_refine_ls_number_reflns         3978
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.045
_refine_ls_R_factor_all          0.0323
_refine_ls_R_factor_gt           0.0237
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0148P)^2^+0.9308P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0495
_refine_ls_wR_factor_ref         0.0518
_reflns_number_gt                3440
_reflns_number_total             3978
_reflns_threshold_expression     >2\s(I)
_cod_data_source_file            jo801397g_si_003.cif
_cod_data_source_block           k08001s
_cod_database_code               4023801