Tailoring atropisomeric maleimides for stereospecific [2 + 2] photocycloaddition-photochemical and photophysical investigations leading to visible-light photocatalysis.
Kumarasamy, Elango; Raghunathan, Ramya; Jockusch, Steffen; Ugrinov, Angel; Sivaguru, J.; Journal of the American Chemical Society 136 (2014) 8729–8737; doi:10.1021/ja5034638

data_4121987
_publ_section_title
;
 Tailoring atropisomeric maleimides for stereospecific [2 + 2]
 photocycloaddition-photochemical and photophysical investigations leading
 to visible-light photocatalysis.
;
_journal_issue                   24
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              8729
_journal_page_last               8737
_journal_paper_doi               10.1021/ja5034638
_journal_volume                  136
_journal_year                    2014
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C20 H17 N O3'
_chemical_formula_sum            'C20 H17 N O3'
_chemical_formula_weight         319.35
_space_group_crystal_system      monoclinic
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_audit_creation_date             2013-11-22
_audit_creation_method
;
Olex2 1.2
(compiled 2013.11.15 svn.r2839 for OlexSys, GUI svn.r4715)
;
_cell_angle_alpha                90
_cell_angle_beta                 112.488(2)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   10.5871(2)
_cell_length_b                   7.2845(2)
_cell_length_c                   10.7784(3)
_cell_measurement_reflns_used    4896
_cell_measurement_temperature    100
_cell_measurement_theta_max      66.25
_cell_measurement_theta_min      4.44
_cell_volume                     768.04(4)
_computing_data_reduction        'SAINT v7.68A (Bruker, 2009)'
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'ShelXL (Sheldrick, 2008)'
_computing_structure_solution    'XS (Sheldrick, 2008)'
_diffrn_ambient_temperature      100.01
_diffrn_measured_fraction_theta_full 0.975
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0293
_diffrn_reflns_av_unetI/netI     0.0242
_diffrn_reflns_Laue_measured_fraction_full 0.975
_diffrn_reflns_Laue_measured_fraction_max 0.996
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            10176
_diffrn_reflns_point_group_measured_fraction_full 0.958
_diffrn_reflns_point_group_measured_fraction_max 0.980
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         66.607
_diffrn_reflns_theta_min         4.440
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.754
_exptl_absorpt_correction_T_max  0.7528
_exptl_absorpt_correction_T_min  0.6857
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2008/1 (Bruker,2008) was used for absorption correction.
wR2(int) was 0.0541 before and 0.0410 after correction.
The Ratio of minimum to maximum transmission is 0.9109.
The \l/2 correction factor is 0.0015.
;
_exptl_crystal_colour            'clear colourless'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.381
_exptl_crystal_description       prism
_exptl_crystal_F_000             336
_exptl_crystal_size_max          0.21
_exptl_crystal_size_mid          0.077
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.139
_refine_diff_density_min         -0.133
_refine_diff_density_rms         0.031
_refine_ls_abs_structure_details
;
 Flack x determined using 1130 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons and Flack (2004), Acta Cryst. A60, s61).
;
_refine_ls_abs_structure_Flack   -0.05(10)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.029
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     218
_refine_ls_number_reflns         2675
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.029
_refine_ls_R_factor_all          0.0279
_refine_ls_R_factor_gt           0.0263
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0366P)^2^+0.1281P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0649
_refine_ls_wR_factor_ref         0.0660
_reflns_Friedel_coverage         0.812
_reflns_Friedel_fraction_full    0.939
_reflns_Friedel_fraction_max     0.961
_reflns_number_gt                2580
_reflns_number_total             2675
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja5034638_si_002.cif
_cod_data_source_block           1R5S6R-2g
_cod_depositor_comments
'Adding full bibliography for 4121977--4121989.cif.'
_cod_original_cell_volume        768.04(3)
_cod_database_code               4121987
_shelxl_version_number           2013-4
_shelx_estimated_absorpt_t_max   0.970
_shelx_estimated_absorpt_t_min   0.858
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2.a Ternary CH refined with riding coordinates:
 C5(H5), C6(H6)
2.b Secondary CH2 refined with riding coordinates:
 C7(H7A,H7B), C8(H8A,H8B)
2.c Aromatic/amide H refined with riding coordinates:
 C12(H12), C21(H21), C13(H13), C24(H24), C11(H11), C20(H20), C22(H22), C23(H23)
2.d Idealised Me refined as rotating group:
 C16(H16A,H16B,H16C)
;
_shelx_res_checksum              11433
_shelx_hkl_checksum              3130