Supramolecular architectures in the reaction products of caffeine with dihalogens: crystal structures of the CT-adduct bis(caffeine)-diiodine and the caffeinium iodine dichloride salt
Isaia, Francesco; Aragoni, Maria Carla; Arca, Massimiliano; Demartin, Francesco; Garau, Alessandra; Lippolis, Vito; Pivetta, Tiziana; Podda, Enrico; New Journal of Chemistry 50 (2026) 5253–5265; doi:10.1039/D5NJ05002B

data_7064293
_publ_section_title
;
 Supramolecular architectures in the reaction products of caffeine with
 dihalogens: crystal structures of the CT-adduct bis(caffeine)-diiodine
 and the caffeinium iodine dichloride salt
;
_journal_issue                   12
_journal_name_full               'New Journal of Chemistry'
_journal_page_first              5253
_journal_page_last               5265
_journal_paper_doi               10.1039/D5NJ05002B
_journal_volume                  50
_journal_year                    2026
_chemical_formula_moiety         '1.92(C8 H10 N4 O2), (I2)'
_chemical_formula_sum            'C15.36 H19.2 I2 N7.68 O3.84'
_chemical_formula_weight         626.66
_space_group_crystal_system      triclinic
_space_group_IT_number           2
_space_group_name_Hall           '-P 1'
_space_group_name_H-M_alt        'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_audit_creation_date             2026-02-06
_audit_creation_method
;
Olex2 1.5
(compiled 2025.07.13 svn.rb7424aed for OlexSys, GUI svn.r7314)
;
_audit_update_record
;
2026-02-09 deposited with the CCDC.	2026-02-20 downloaded from the CCDC.
;
_cell_angle_alpha                106.896(3)
_cell_angle_beta                 94.066(3)
_cell_angle_gamma                91.916(3)
_cell_formula_units_Z            4
_cell_length_a                   9.1739(7)
_cell_length_b                   14.8378(11)
_cell_length_c                   16.1206(13)
_cell_measurement_reflns_used    9687
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      28.358
_cell_measurement_theta_min      2.618
_cell_volume                     2091.0(3)
_computing_cell_refinement       'SAINT V8.40B (?, 2016)'
_computing_data_reduction        'SAINT V8.40B (?, 2016)'
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXT 2014/5 (Sheldrick, 2014)'
_diffrn_ambient_temperature      100(2)
_diffrn_detector                 'Bruker PHOTON II area detector'
_diffrn_detector_area_resol_mean 7.9
_diffrn_detector_type            'CPAD area detector'
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device       'Bruker D8 Venture'
_diffrn_measurement_device_type  'Bruker D8 Venture'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  'mirror optics'
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0343
_diffrn_reflns_av_unetI/netI     0.0328
_diffrn_reflns_Laue_measured_fraction_full 0.998
_diffrn_reflns_Laue_measured_fraction_max 0.992
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            37770
_diffrn_reflns_point_group_measured_fraction_full 0.998
_diffrn_reflns_point_group_measured_fraction_max 0.992
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         28.363
_diffrn_reflns_theta_min         2.229
_diffrn_source                   'microfocus sealed X-ray tube'
_diffrn_source_current           1.0
_diffrn_source_power             0.05
_diffrn_source_type              'Incoatec I\ms'
_diffrn_source_voltage           50.0
_exptl_absorpt_coefficient_mu    3.050
_exptl_absorpt_correction_T_max  0.745686
_exptl_absorpt_correction_T_min  0.549441
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
 TWINABS-2012/1 (Bruker,2012) was used for absorption correction.
 
For component 1:
 wR2(int) was 0.0794 before and 0.0581 after correction.
 The Ratio of minimum to maximum transmission is 0.74.

Final HKLF 4 output contains 65813 reflections, Rint = 0.0481
 (23622 with I > 3sig(I), Rint = 0.0396)
;
_exptl_crystal_colour            orange
_exptl_crystal_colour_primary    orange
_exptl_crystal_density_diffrn    1.991
_exptl_crystal_description       prism
_exptl_crystal_F_000             1207.4
_exptl_crystal_size_max          0.16
_exptl_crystal_size_mid          0.09
_exptl_crystal_size_min          0.02
_refine_diff_density_max         1.153
_refine_diff_density_min         -0.909
_refine_diff_density_rms         0.135
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.091
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     569
_refine_ls_number_reflns         10371
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.091
_refine_ls_R_factor_all          0.0404
_refine_ls_R_factor_gt           0.0316
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0284P)^2^+5.2431P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0741
_refine_ls_wR_factor_ref         0.0795
_reflns_Friedel_coverage         0.000
_reflns_number_gt                8857
_reflns_number_total             10371
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5nj05002b2.cif
_cod_data_source_block           caf2_i2_2025cesar051
_cod_depositor_comments
'Adding full bibliography for 7064293--7064294.cif.'
_cod_original_formula_sum        'C15.36 H19.20 I2 N7.68 O3.84'
_cod_database_code               7064293
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_max   0.942
_shelx_estimated_absorpt_t_min   0.641
_olex2_refinement_description
;
1. Restrained distances
 I4-I3 \\sim I4B-I3B
 with sigma of 0.02
2. Others
 Fixed Sof: I4(0.96) I3(0.96) I2(0.96) I1(0.96) N2(0.96) O5(0.96) N5(0.96)
 O8(0.96) O3(0.96) O6(0.96) N6(0.96) N8(0.96) O1(0.96) O2(0.96) N4(0.96)
 N7(0.96) O7(0.96) N9(0.96) N12(0.96) N11(0.96) C13(0.96) C9(0.96) H9(0.96)
 O4(0.96) C8(0.96) H8A(0.96) H8B(0.96) H8C(0.96) C22(0.96) H22A(0.96)
 H22B(0.96) H22C(0.96) N3(0.96) N10(0.96) C4(0.96) C16(0.96) H16A(0.96)
 H16B(0.96) H16C(0.96) C10(0.96) N16(0.96) N13(0.96) N15(0.96) C1(0.96)
 H1(0.96) C25(0.96) H25(0.96) C5(0.96) C24(0.96) H24A(0.96) H24B(0.96)
 H24C(0.96) N14(0.96) C6(0.96) H6A(0.96) H6B(0.96) H6C(0.96) C7(0.96) H7A(0.96)
 H7B(0.96) H7C(0.96) C2(0.96) C3(0.96) C27(0.96) C14(0.96) H14A(0.96)
 H14B(0.96) H14C(0.96) C20(0.96) C30(0.96) H30A(0.96) H30B(0.96) H30C(0.96)
 C29(0.96) C28(0.96) C21(0.96) C12(0.96) C32(0.96) H32A(0.96) H32B(0.96)
 H32C(0.96) C19(0.96) C15(0.96) H15A(0.96) H15B(0.96) H15C(0.96) C31(0.96)
 H31A(0.96) H31B(0.96) H31C(0.96) C11(0.96) C18(0.96) C26(0.96) C17(0.96)
 H17(0.96) C23(0.96) H23A(0.96) H23B(0.96) H23C(0.96) I1B(0.04) N1(0.96)
 I2B(0.04) I3B(0.04) I4B(0.04)
3.a Aromatic/amide H refined with riding coordinates:
 C9(H9), C1(H1), C25(H25), C17(H17)
3.b Idealised Me refined as rotating group:
 C8(H8A,H8B,H8C), C22(H22A,H22B,H22C), C16(H16A,H16B,H16C), C24(H24A,H24B,
 H24C), C6(H6A,H6B,H6C), C7(H7A,H7B,H7C), C14(H14A,H14B,H14C), C30(H30A,H30B,
 H30C), C32(H32A,H32B,H32C), C15(H15A,H15B,H15C), C31(H31A,H31B,H31C), C23(H23A,
 H23B,H23C)
;
_shelx_res_checksum              66547
_olex2_submission_special_instructions 'No special instructions were received'