Atropisomerization in N-aryl-2(1H)-pyrimidin-(thi)ones: A Ring-Opening/Rotation/Ring-Closure Process in Place of a Classical Rotation around the Pivot Bond
Ennaji Najahi; Nicolas Vanthuyne; Françoise Nepveu; Marion Jean; Ibon Alkorta; José Elguero; Christian Roussel; Journal of Organic Chemistry 78 (2013) 12577–12584; doi:10.1021/jo402149f

data_4028871
_publ_section_title
;
 Atropisomerization in N-aryl-2(1H)-pyrimidin-(thi)ones: A
 Ring-Opening/Rotation/Ring-Closure Process in Place of a Classical
 Rotation around the Pivot Bond
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              12577
_journal_page_last               12584
_journal_paper_doi               10.1021/jo402149f
_journal_volume                  78
_journal_year                    2013
_chemical_formula_moiety         'C21 H14 N4 O, C H4 O'
_chemical_formula_sum            'C22 H18 N4 O2'
_chemical_formula_weight         370.41
_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
_cell_angle_alpha                90
_cell_angle_beta                 105.839(4)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   11.1402(4)
_cell_length_b                   19.9585(6)
_cell_length_c                   8.4770(3)
_cell_measurement_reflns_used    7950
_cell_measurement_temperature    180
_cell_measurement_theta_max      29
_cell_measurement_theta_min      3
_cell_volume                     1813.23(11)
_computing_cell_refinement       'CrysAlis RED, (Oxford Diffraction, 2002)'
_computing_data_collection       'Xcalibur, (Oxford Diffraction, 2002)'
_computing_data_reduction        'CrysAlis RED, (Oxford Diffraction, 2002)'
_computing_molecular_graphics    'CAMERON (Watkin et al., 1996)'
_computing_publication_material  'CRYSTALS (Betteridge et al., 2003)'
_computing_structure_refinement  'CRYSTALS (Betteridge et al., 2003)'
_computing_structure_solution    'SIR92 (Altomare et al., 1994)'
_diffrn_ambient_temperature      180
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device       'Oxford Diffraction XCALIBUR'
_diffrn_measurement_device_type  Area
_diffrn_measurement_method       '\f & \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.030
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       27
_diffrn_reflns_limit_k_min       -27
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            17459
_diffrn_reflns_theta_full        28.528
_diffrn_reflns_theta_max         29.110
_diffrn_reflns_theta_min         2.698
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.090
_exptl_absorpt_correction_T_max  0.99
_exptl_absorpt_correction_T_min  0.94
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Blessing, acta cryst. (1995), a51, 33-38'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.357
_exptl_crystal_description       block
_exptl_crystal_F_000             776
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.32
_refine_diff_density_min         -0.17
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.1242
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     253
_refine_ls_number_reflns         3133
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0563
_refine_ls_R_factor_gt           0.0373
_refine_ls_shift/su_max          0.000158
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details
;
 Method, part 1, Chebychev polynomial, (Watkin, 1994, Prince, 1982) 
 [weight] = 1.0/[A~0~*T~0~(x)+A~1~*T~1~(x) ... +A~n-1~]*T~n-1~(x)] 
 where A~i~ are the Chebychev coefficients listed below and x= Fcalc/Fmax 
 Method = Robust Weighting (Prince, 1982) 
 W = [weight] * [1-(deltaF/6*sigmaF)^2^]^2^ 
 A~i~ are: 
 2.67 -0.461 1.79 
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.0504
_refine_ls_wR_factor_gt          0.0421
_refine_ls_wR_factor_ref         0.0403
_reflns_limit_h_max              14
_reflns_limit_h_min              -15
_reflns_limit_k_max              27
_reflns_limit_k_min              0
_reflns_limit_l_max              11
_reflns_limit_l_min              0
_reflns_number_gt                3438
_reflns_number_total             4850
_reflns_threshold_expression     I>2.0\s(I)
_oxford_refine_ls_r_factor_ref   0.0345
_oxford_reflns_number_all        4839
_oxford_reflns_threshold_expression_ref I>3.0\s(I)
_cod_data_source_file            jo402149f_si_001.cif
_cod_data_source_block           1
_cod_original_sg_symbol_H-M      'P 1 21/c 1 '
_cod_database_code               4028871