Proton-Transfer Polymerization by N-Heterocyclic Carbenes: Monomer and Catalyst Scopes and Mechanism for Converting Dimethacrylates into Unsaturated Polyesters.
Hong, Miao; Tang, Xiaoyan; Falivene, Laura; Caporaso, Lucia; Cavallo, Luigi; Chen, Eugene Y.-X.; Journal of the American Chemical Society 138 (2016) 2021–2035; doi:10.1021/jacs.5b13019

data_4130033
_publ_section_title
;
 Proton-Transfer Polymerization by N-Heterocyclic Carbenes: Monomer and
 Catalyst Scopes and Mechanism for Converting Dimethacrylates into
 Unsaturated Polyesters.
;
_journal_issue                   6
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              2021
_journal_page_last               2035
_journal_paper_doi               10.1021/jacs.5b13019
_journal_volume                  138
_journal_year                    2016
_chemical_formula_moiety         'C23 H23 N3 O3'
_chemical_formula_sum            'C23 H23 N3 O3'
_chemical_formula_weight         389.44
_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'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                90
_cell_angle_beta                 90.0144(18)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   10.2142(4)
_cell_length_b                   18.8081(7)
_cell_length_c                   10.5146(4)
_cell_measurement_reflns_used    9938
_cell_measurement_temperature    120(2)
_cell_measurement_theta_max      28.98
_cell_measurement_theta_min      2.94
_cell_volume                     2019.96(13)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      120(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0504
_diffrn_reflns_av_unetI/netI     0.0404
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 1.000
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -22
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            34271
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 1.000
_diffrn_reflns_theta_full        24.708
_diffrn_reflns_theta_max         24.708
_diffrn_reflns_theta_min         1.937
_exptl_absorpt_coefficient_mu    0.086
_exptl_absorpt_correction_T_max  0.7466
_exptl_absorpt_correction_T_min  0.6777
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SCALE (Bruker, 2009)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.281
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       rod
_exptl_crystal_F_000             824
_exptl_crystal_size_max          0.579
_exptl_crystal_size_mid          0.104
_exptl_crystal_size_min          0.096
_refine_diff_density_max         0.925
_refine_diff_density_min         -0.327
_refine_diff_density_rms         0.089
_refine_ls_abs_structure_details
; 
 Flack x determined using 2556 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259). 
;
_refine_ls_abs_structure_Flack   1.0(5)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.146
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     529
_refine_ls_number_reflns         6862
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.146
_refine_ls_R_factor_all          0.0557
_refine_ls_R_factor_gt           0.0426
_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^)+(0.0782P)^2^+0.4742P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1091
_refine_ls_wR_factor_ref         0.1393
_reflns_Friedel_coverage         0.934
_reflns_Friedel_fraction_full    0.999
_reflns_Friedel_fraction_max     0.999
_reflns_number_gt                5977
_reflns_number_total             6862
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja5b13019_si_002.cif
_cod_data_source_block           ec106
_cod_depositor_comments
;
The following automatic conversions were performed:

data item '_exptl_crystal_density_meas' value 'not measured' was
changed to '?' -- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 6909 2019-04-08 15:41:33Z antanas 
;
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               4130033
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.952
_shelx_estimated_absorpt_t_max   0.992
_shelx_res_checksum              63096
_shelx_hkl_checksum              81310