Synthesis and stability of cyclic α-hydrogen nitroxides.
Toledo, Hila; Amar, Michal; Bar, Sukanta; Iron, Mark A.; Fridman, Natalia; Tumanskii, Boris; Shimon, Linda J. W.; Botoshansky, Mark; Szpilman, Alex M.; Organic & biomolecular chemistry 13 (2015) 10726–10733; doi:10.1039/c5ob01443c

data_7154671
_publ_section_title
;
 Synthesis and stability of cyclic \a-hydrogen nitroxides.
;
_journal_issue                   43
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              10726
_journal_page_last               10733
_journal_paper_doi               10.1039/c5ob01443c
_journal_volume                  13
_journal_year                    2015
_chemical_absolute_configuration unk
_chemical_formula_moiety         'C20 H23 N O4'
_chemical_formula_sum            'C20 H23 N O4'
_chemical_formula_weight         341.39
_chemical_name_common            Szpilman9
_chemical_name_systematic
'ethyl 3-(tert-butyl)-1-methyl-4,9-dioxo-2,3,4,9-tetrahydro-1H-benzo[f]isoindole-1-carboxylate'
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_block_doi                 10.5517/cc1jbpj2
_audit_creation_method           SHELXL-97
_audit_update_record
;
2015-07-03 deposited with the CCDC.
2015-08-24 downloaded from the CCDC.
;
_cell_angle_alpha                90.00
_cell_angle_beta                 95.5320(11)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   11.1710(3)
_cell_length_b                   8.5890(3)
_cell_length_c                   19.7280(7)
_cell_measurement_reflns_used    3824
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      27.75
_cell_measurement_theta_min      1.83
_cell_volume                     1884.04(11)
_computing_cell_refinement       'DENZO HKL2000 (Otwinowski & Minor 1997)'
_computing_data_collection       'Collect (Nonius, 2006)'
_computing_data_reduction        'DENZO HKL2000 (Otwinowski & Minor 1997)'
_computing_molecular_graphics    'Mercury 3.5'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean 95
_diffrn_measured_fraction_theta_full 0.991
_diffrn_measured_fraction_theta_max 0.991
_diffrn_measurement_device_type  'Nonius KappaCCD'
_diffrn_measurement_method       'phi- and omega-scans'
_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  0.0510
_diffrn_reflns_av_sigmaI/netI    0.0408
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            3311
_diffrn_reflns_theta_full        25.04
_diffrn_reflns_theta_max         25.04
_diffrn_reflns_theta_min         1.83
_diffrn_standards_decay_%        none
_diffrn_standards_interval_count none
_diffrn_standards_interval_time  none
_diffrn_standards_number         none
_exptl_absorpt_coefficient_mu    0.084
_exptl_absorpt_correction_T_max  0.9851
_exptl_absorpt_correction_T_min  0.9778
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
; 
'HKL Denzo and Scalepack (Otwinowski & Minor 1997)'  
;
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.204
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             728
_exptl_crystal_size_max          0.27
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.18
_refine_diff_density_max         0.173
_refine_diff_density_min         -0.145
_refine_diff_density_rms         0.032
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.035
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     226
_refine_ls_number_reflns         3311
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.035
_refine_ls_R_factor_all          0.0845
_refine_ls_R_factor_gt           0.0577
_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^)+(0.0669P)^2^+0.5132P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1357
_refine_ls_wR_factor_ref         0.1491
_reflns_number_gt                2417
_reflns_number_total             3311
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c5ob01443c2.cif
_cod_data_source_block           Szpilman9
_cod_depositor_comments
'Adding full bibliography for 7154666--7154672.cif.'
_cod_original_sg_symbol_H-M      'P 21/c '
_cod_database_code               7154671