Influence of achiral units with gem-dimethyl substituents on the helical character of aliphatic oligourea foldamers
Juliette Fremaux; Christel Dolain; Brice Kauffmann; Jonathan Clayden; Gilles Guichard; Chem.Commun. 49 (2013) 7415–; doi:10.1039/c3cc40961a

data_7109585
_publ_section_title
;
 Influence of achiral units with gem-dimethyl substituents on the helical
 character of aliphatic oligourea foldamers
;
_journal_name_full               Chem.Commun.
_journal_page_first              7415
_journal_paper_doi               10.1039/c3cc40961a
_journal_volume                  49
_journal_year                    2013
_chemical_absolute_configuration rm
_chemical_formula_sum            'C50 H101 N17 O12'
_chemical_formula_weight         1132.48
_chemical_name_systematic
;
?
;
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_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
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 106.39(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   10.658(2)
_cell_length_b                   18.807(4)
_cell_length_c                   17.672(4)
_cell_measurement_reflns_used    14638
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      52.63
_cell_measurement_theta_min      2.61
_cell_volume                     3398.3(13)
_computing_cell_refinement       'SAINT V7.68A integration software'
_computing_data_collection       'Bruker APEX2 software'
_computing_molecular_graphics    'WinGX publication routines (Farrugia, 1999)'
_computing_publication_material  'WinGX publication routines (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXD (Sheldrick, 2008)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector                 'PLATINUM-135 CCD'
_diffrn_measured_fraction_theta_full 0.923
_diffrn_measured_fraction_theta_max 0.923
_diffrn_measurement_device_type  '\k-geometry diffractometer'
_diffrn_measurement_method       'omega scans'
_diffrn_radiation_monochromator  none
_diffrn_radiation_source         'microstar rotatinf anode'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0372
_diffrn_reflns_av_sigmaI/netI    0.0527
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            13718
_diffrn_reflns_theta_full        52.63
_diffrn_reflns_theta_max         52.63
_diffrn_reflns_theta_min         2.61
_exptl_absorpt_coefficient_mu    0.656
_exptl_absorpt_correction_T_max  0.7516
_exptl_absorpt_correction_T_min  0.6505
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2008/1 - Bruker AXS area detector scaling and absorption correction
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.107
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             1232
_exptl_crystal_size_max          0.1
_exptl_crystal_size_mid          0.02
_exptl_crystal_size_min          0.01
_refine_diff_density_max         0.413
_refine_diff_density_min         -0.207
_refine_diff_density_rms         0.048
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.3(5)
_refine_ls_extinction_coef       0.00035(18)
_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   1.072
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     708
_refine_ls_number_reflns         5521
_refine_ls_number_restraints     4
_refine_ls_restrained_S_all      1.077
_refine_ls_R_factor_all          0.1028
_refine_ls_R_factor_gt           0.0676
_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^)+(0.1391P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1834
_refine_ls_wR_factor_ref         0.2180
_reflns_number_gt                3648
_reflns_number_total             5521
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c3cc40961a.txt
_cod_data_source_block           jf374_compound5
_cod_original_cell_volume        3398.2(12)
_cod_original_sg_symbol_H-M      P2(1)
_cod_original_formula_sum        'C25 H50.50 N8.50 O6'
_cod_database_code               7109585