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_4121977
_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_formula_moiety         'C20 H17 N O3'
_chemical_formula_sum            'C20 H17 N O3'
_chemical_formula_weight         319.35
_space_group_crystal_system      orthorhombic
_space_group_IT_number           61
_space_group_name_Hall           '-P 2ac 2ab'
_space_group_name_H-M_alt        'P b c a'
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_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                 90
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   10.9776(3)
_cell_length_b                   9.9868(3)
_cell_length_c                   28.5806(8)
_cell_measurement_reflns_used    9891
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      66.631
_cell_measurement_theta_min      3.092
_cell_volume                     3133.32(15)
_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    'ShelXS (Sheldrick, 2008)'
_diffrn_ambient_temperature      100.0
_diffrn_measured_fraction_theta_full 0.976
_diffrn_measured_fraction_theta_max 0.997
_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  0.0241
_diffrn_reflns_av_unetI/netI     0.0135
_diffrn_reflns_Laue_measured_fraction_full 0.976
_diffrn_reflns_Laue_measured_fraction_max 0.997
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       34
_diffrn_reflns_limit_l_min       -33
_diffrn_reflns_number            20129
_diffrn_reflns_point_group_measured_fraction_full 0.976
_diffrn_reflns_point_group_measured_fraction_max 0.997
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         66.626
_diffrn_reflns_theta_min         3.092
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.739
_exptl_absorpt_correction_T_max  0.7528
_exptl_absorpt_correction_T_min  0.6551
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2008/1 (Bruker,2008) was used for absorption correction.
wR2(int) was 0.0593 before and 0.0360 after correction.
The Ratio of minimum to maximum transmission is 0.8702.
The \l/2 correction factor is 0.0015.
;
_exptl_crystal_colour            'clear yellow'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_primary    yellow
_exptl_crystal_density_diffrn    1.354
_exptl_crystal_description       plate
_exptl_crystal_F_000             1344
_exptl_crystal_size_max          0.27
_exptl_crystal_size_mid          0.22
_exptl_crystal_size_min          0.07
_refine_diff_density_max         0.312
_refine_diff_density_min         -0.188
_refine_diff_density_rms         0.035
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.054
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     218
_refine_ls_number_reflns         2756
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.054
_refine_ls_R_factor_all          0.0339
_refine_ls_R_factor_gt           0.0324
_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^)+(0.0359P)^2^+1.4781P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0803
_refine_ls_wR_factor_ref         0.0814
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2623
_reflns_number_total             2756
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja5034638_si_002.cif
_cod_data_source_block           2g
_cod_depositor_comments
'Adding full bibliography for 4121977--4121989.cif.'
_cod_database_code               4121977
_shelxl_version_number           2013-4
_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 Secondary CH2 refined with riding coordinates:
 C3(H3A,H3B)
2.b Aromatic/amide H refined with riding coordinates:
 C2(H2), C20(H20), C19(H19), C18(H18), C8(H8), C7(H7), C6(H6), C13(H13),
 C17(H17), C16(H16)
2.c X=CH2 refined with riding coordinates:
 C1(H1A,H1B)
2.d Idealised Me refined as rotating group:
 C22(H22A,H22B,H22C)
;
_shelx_res_checksum              64431
_shelx_hkl_checksum              25234