Tandem Diels–Alder reaction overrules entropy: the gate to thermally stable, yet thermally recyclable furan-based polymers
Zakharova, Daria V.; Aysin, Rinat R.; Pavlov, Alexander A.; Khanin, Dmirty A.; Platonova, Elena O.; Nelyubina, Yulia V.; Polezhaev, Alexander V.; Green Chemistry 27 (2025) 2263–2275; doi:10.1039/D4GC04846F

data_7249746
_publ_section_title
;
 Tandem Diels--Alder reaction overrules entropy: the gate to thermally
 stable, yet thermally recyclable furan-based polymers
;
_journal_issue                   8
_journal_name_full               'Green Chemistry'
_journal_page_first              2263
_journal_page_last               2275
_journal_paper_doi               10.1039/D4GC04846F
_journal_volume                  27
_journal_year                    2025
_chemical_formula_moiety         'C26 H22 N2 O4'
_chemical_formula_sum            'C26 H22 N2 O4'
_chemical_formula_weight         426.45
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_audit_creation_date             2024-07-11
_audit_creation_method
;
Olex2 1.5
(compiled 2023.02.24 svn.rf166f9f3 for OlexSys, GUI svn.r6725)
;
_audit_update_record
;
2024-07-11 deposited with the CCDC.	2025-01-07 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 103.215(7)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   14.310(4)
_cell_length_b                   14.559(4)
_cell_length_c                   10.188(3)
_cell_measurement_reflns_used    891
_cell_measurement_temperature    120
_cell_measurement_theta_max      20.96
_cell_measurement_theta_min      2.48
_cell_volume                     2066.4(10)
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'XL  (Sheldrick, 2008)'
_computing_structure_solution    'SHELXT 2014/4 (Sheldrick, 2014)'
_diffrn_ambient_temperature      120
_diffrn_measured_fraction_theta_full 0.969
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker ApexII DUO CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.1764
_diffrn_reflns_av_unetI/netI     0.1265
_diffrn_reflns_Laue_measured_fraction_full 0.969
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            18275
_diffrn_reflns_point_group_measured_fraction_full 0.969
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         24.999
_diffrn_reflns_theta_min         2.023
_exptl_absorpt_coefficient_mu    0.093
_exptl_absorpt_correction_T_max  0.7461
_exptl_absorpt_correction_T_min  0.6085
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2008/1 (Bruker,2008) was used for absorption correction.
wR2(int) was 0.0861 before and 0.0692 after correction.
The Ratio of minimum to maximum transmission is 0.8156.
The \l/2 correction factor is 0.0015.
;
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.371
_exptl_crystal_description       prism
_exptl_crystal_F_000             896
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.25
_refine_diff_density_max         0.274
_refine_diff_density_min         -0.233
_refine_diff_density_rms         0.058
_refine_ls_extinction_coef       0.0032(4)
_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   0.972
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     290
_refine_ls_number_reflns         3632
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.972
_refine_ls_R_factor_all          0.1401
_refine_ls_R_factor_gt           0.0552
_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^)+(0.0317P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0879
_refine_ls_wR_factor_ref         0.1145
_reflns_Friedel_coverage         0.000
_reflns_number_gt                1879
_reflns_number_total             3632
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d4gc04846f2.cif
_cod_data_source_block           5a
_cod_depositor_comments
'Adding full bibliography for 7249746--7249747.cif.'
_cod_original_cell_volume        2066.3(10)
_cod_database_code               7249746
_shelxl_version_number           2014/6
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups
2.a Ternary CH refined with riding coordinates:
 C3(H3), C4(H4), C5(H5), C6(H6), C8(H8), C15(H15)
2.b Secondary CH2 refined with riding coordinates:
 C19(H19A,H19B), C20(H20A,H20B)
2.c Aromatic/amide H refined with riding coordinates:
 C10(H10), C11(H11), C12(H12), C13(H13), C14(H14), C16(H16), C17(H17),
 C22(H22), C23(H23), C24(H24), C25(H25), C26(H26)
;
_shelx_res_checksum              44714
_shelx_hkl_checksum              7016
_olex2_submission_special_instructions 'No special instructions were received'