Development of Chiral, Bifunctional Thiosquaramides: Enantioselective Michael Additions of Barbituric Acids to Nitroalkenes.
Rombola, Michael; Sumaria, Chintan S.; Montgomery, Thomas D.; Rawal, Viresh H.; Journal of the American Chemical Society 139 (2017) 5297–5300; doi:10.1021/jacs.7b01115

data_4125908
_publ_section_title
;
 Development of Chiral, Bifunctional Thiosquaramides: Enantioselective
 Michael Additions of Barbituric Acids to Nitroalkenes.
;
_journal_issue                   15
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              5297
_journal_page_last               5300
_journal_paper_doi               10.1021/jacs.7b01115
_journal_volume                  139
_journal_year                    2017
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C16 H27 N3 S2'
_chemical_formula_sum            'C16 H27 N3 S2'
_chemical_formula_weight         325.52
_space_group_crystal_system      orthorhombic
_space_group_IT_number           19
_space_group_name_Hall           'P 2ac 2ab'
_space_group_name_H-M_alt        'P 21 21 21'
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     dual
_atom_sites_solution_secondary   difmap
_audit_creation_date             2016-09-02
_audit_creation_method
;
Olex2 1.2
(compiled 2016.08.25 svn.r3337 for OlexSys, GUI svn.r5221)
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   9.6429(2)
_cell_length_b                   18.4345(4)
_cell_length_c                   20.8434(4)
_cell_measurement_reflns_used    9918
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      78.12
_cell_measurement_theta_min      4.24
_cell_volume                     3705.17(13)
_computing_cell_refinement       'SAINT V.8.35A (Bruker AXS Inc., 2013)'
_computing_data_collection       'APEX3 v.2015.9-0 (Bruker AXS Inc., 2015)'
_computing_data_reduction        'SAINT V.8.35A (Bruker AXS Inc., 2013)'
_computing_molecular_graphics
;
OLEX2: a complete structure solution, refinement and analysis program 
Dolomanov et al., 2009

Mercury: visualization and analysis of crystal structures
Macrae, et al., 2006

O. V. Dolomanov, L. J. Bourhis, R. J. Gildea, J. A. K. Howard and H. Puschmann.
J. Appl. Cryst. (2009). 42, 339-341;

C. F. Macrae, P. R. Edgington, P. McCabe, E. Pidcock, G. P. Shields, R. Taylor,
M. Towler and J. van de Streek, J. Appl. Cryst. (2006). 39, 453-457.
;
_computing_publication_material
;
 APEX3 v.2015.5-2 (Bruker AXS Inc., 2015)
 OLEX2 (Dolomanov et al., 2009)
;
_computing_structure_refinement  'XL-2014/7 (Sheldrick, 2015b)'
_computing_structure_solution    'XT 2014/5 (Sheldrick, 2015a)'
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 10.4167
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.973
_diffrn_measurement_device_type  'Bruker D8 Venture PHOTON 100 CMOS'
_diffrn_measurement_method       'omega and phi scans'
_diffrn_radiation_monochromator  mirrors
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0368
_diffrn_reflns_av_unetI/netI     0.0320
_diffrn_reflns_Laue_measured_fraction_full 0.995
_diffrn_reflns_Laue_measured_fraction_max 0.973
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            34979
_diffrn_reflns_point_group_measured_fraction_full 0.996
_diffrn_reflns_point_group_measured_fraction_max 0.961
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         78.108
_diffrn_reflns_theta_min         3.200
_diffrn_source                   'INCOATEC ImuS micro-focus source'
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    2.573
_exptl_absorpt_correction_T_max  0.7542
_exptl_absorpt_correction_T_min  0.5277
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2014/4 (Bruker,2014/4) was used for absorption correction.
wR2(int) was 0.1117 before and 0.0637 after correction.
The Ratio of minimum to maximum transmission is 0.6997.
The \l/2 correction factor is 0.00150.
;
_exptl_crystal_colour            yellow
_exptl_crystal_colour_primary    yellow
_exptl_crystal_density_diffrn    1.167
_exptl_crystal_description       block
_exptl_crystal_F_000             1408
_exptl_crystal_size_max          0.42
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.16
_refine_diff_density_max         0.283
_refine_diff_density_min         -0.133
_refine_diff_density_rms         0.041
_refine_ls_abs_structure_details
;
 Flack x determined using 3048 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.010(5)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.962
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     401
_refine_ls_number_reflns         7635
_refine_ls_number_restraints     4
_refine_ls_restrained_S_all      0.962
_refine_ls_R_factor_all          0.0280
_refine_ls_R_factor_gt           0.0255
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0345P)^2^+0.5803P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0606
_refine_ls_wR_factor_ref         0.0620
_reflns_Friedel_coverage         0.766
_reflns_Friedel_fraction_full    0.996
_reflns_Friedel_fraction_max     0.946
_reflns_number_gt                7261
_reflns_number_total             7635
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja7b01115_si_001.cif
_cod_data_source_block           cu_romb
_cod_depositor_comments          'Adding full bibliography for 4125908.cif.'
_cod_database_code               4125908
_shelx_estimated_absorpt_t_max   0.684
_shelx_estimated_absorpt_t_min   0.411
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups, All N(H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2. Restrained distances
 N5-H5 = N1-H1 = N2-H2 = N4-H4
 0.84 with sigma of 0.02
3.a Ternary CH refined with riding coordinates:
 C9(H9), C14(H14), C25(H25), C30(H30)
3.b Secondary CH2 refined with riding coordinates:
 C10(H10A,H10B), C11(H11A,H11B), C12(H12A,H12B), C13(H13A,H13B), C26(H26A,
 H26B), C27(H27A,H27B), C28(H28A,H28B), C29(H29A,H29B)
3.c Idealised Me refined as rotating group:
 C1(H1A,H1B,H1C), C2(H2A,H2B,H2C), C3(H3A,H3B,H3C), C15(H15A,H15B,H15C),
 C16(H16A,H16B,H16C), C17(H17A,H17B,H17C), C18(H18A,H18B,H18C), C19(H19A,H19B,
 H19C), C31(H31A,H31B,H31C), C32(H32A,H32B,H32C)
;
_shelx_res_checksum              94232
_shelx_hkl_checksum              74815
_shelx_shelxl_version_number     2014/7
_olex2_submission_special_instructions 'No special instructions were received'