Heteroaryl iminothioindoxyl (HA-ITI) photoswitches <i>via</i> regioselective aza-Wittig synthesis: unifying red-shifted absorption, large <i>E</i>/<i>Z</i> band separation, and tunable thermal recovery.
Chen-Wu, Jialei; Benitez-Martin, Carlos; González-Delgado, José A; de Jong, Flip; Fron, Eduard; Steurs, Gert; Martínez-Martínez, Antonio J; Nájera, Francisco; Grøtli, Morten; Hofkens, Johan; Andréasson, Joakim; Pischel, Uwe; Chemical science 17 (2026) 3658–3668; doi:10.1039/d5sc08074f

data_1576604
_publ_section_title
;
 Heteroaryl iminothioindoxyl (HA-ITI) photoswitches <i>via</i>
 regioselective aza-Wittig synthesis: unifying red-shifted absorption,
 large <i>E</i>/<i>Z</i> band separation, and tunable thermal recovery.
;
_journal_issue                   7
_journal_name_full               'Chemical science'
_journal_page_first              3658
_journal_page_last               3668
_journal_paper_doi               10.1039/d5sc08074f
_journal_volume                  17
_journal_year                    2026
_chemical_formula_moiety         'C16 H11 N3 O S'
_chemical_formula_sum            'C16 H11 N3 O S'
_chemical_formula_weight         293.34
_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             2025-02-07
_audit_creation_method
;
Olex2 1.5-ac6-020
(compiled 2024.02.14 svn.r2f8d729c for Rigaku Oxford Diffraction, GUI svn.r6966)
;
_audit_update_record
;
2025-03-14 deposited with the CCDC.	2025-12-15 downloaded from the CCDC.
;
_cell_angle_alpha                81.1440(10)
_cell_angle_beta                 82.1160(10)
_cell_angle_gamma                64.1260(10)
_cell_formula_units_Z            4
_cell_length_a                   7.62660(10)
_cell_length_b                   7.92250(10)
_cell_length_c                   24.4377(3)
_cell_measurement_reflns_used    35456
_cell_measurement_temperature    150.00(10)
_cell_measurement_theta_max      76.5610
_cell_measurement_theta_min      3.6680
_cell_volume                     1308.64(3)
_computing_cell_refinement       'CrysAlisPro 1.171.43.144a (Rigaku OD, 2024)'
_computing_data_collection
'CrysAlisPro system (CCD 43.143a 64-bit (release 25-10-2024))'
_computing_data_reduction        'CrysAlisPro 1.171.43.144a (Rigaku OD, 2024)'
_computing_molecular_graphics    'Olex2 1.5-ac6-020 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5-ac6-020 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2019/3 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT  (Sheldrick, 2015)'
_diffrn_ambient_environment      N~2~
_diffrn_ambient_temperature      150.00(10)
_diffrn_detector                 'Hybrid Pixel Array Detector'
_diffrn_detector_area_resol_mean 10.0000
_diffrn_detector_type            'HyPix-Arc 100'
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.991
_diffrn_measurement_details
;
List of Runs (angles in degrees, time in seconds):

  # Type    Start    End  Width  t~exp~   \w     \q     \k     \f   Frames
  1  \w     -1.00  89.00   0.50    0.50    --   52.16 -99.00 145.00  180
  2  \w    -80.00  13.00   0.50    0.50    --  -54.91  99.00-109.00  186
  3  \w   -145.00 -86.00   0.50    0.50    --  -77.84 -99.00 145.00  118
  4  \w    -80.00 -10.00   0.50    0.50    --  -77.84  99.00-109.00  140
  5  \w     36.00 106.00   0.50    2.00    --  102.95 -99.00 145.00  140
  6  \w    107.00 170.00   0.50    2.00    --  102.95  99.00-109.00  126
  7  \w     -4.00  22.00   0.50    0.50    --   34.00 100.00  46.05   52
  8  \w     -1.00  89.00   0.50    0.50    --   52.16 -99.00  30.00  180
  9  \w     -1.00  89.00   0.50    0.50    --   52.16 -99.00  30.00  180
 10  \w    -80.00  13.00   0.50    0.50    --  -54.91  99.00-109.00  186
 11  \w   -122.00 -30.00   0.50    0.50    --  -54.91 -77.00 -30.00  184
 12  \w     38.00 129.00   0.50    0.50    --   62.00  77.00  65.98  182
 13  \w    -40.00   0.00   0.50    0.50    --  -77.84  30.00 -90.00   80
 14  \w    -99.00 -11.00   0.50    0.50    --  -77.84  77.00-180.00  176
 15  \w    -35.00  -2.00   0.50    0.50    --  -77.84  15.00  90.00   66
 16  \w    -35.00  -2.00   0.50    0.50    --  -77.84  15.00-120.00   66
 17  \w    -99.00 -11.00   0.50    0.50    --  -77.84  77.00-180.00  176
 18  \w   -153.00 -62.00   0.50    2.00    --  -86.25 -77.00   0.11  182
 19  \w     36.00 105.00   0.50    2.00    --  102.95 -95.00  30.00  138
 20  \w     34.00 111.00   0.50    2.00    --  102.95-125.00 -90.00  154
 21  \w     34.00 111.00   0.50    2.00    --  102.95-125.00 120.00  154
 22  \w     34.00 111.00   0.50    2.00    --  102.95-125.00 -90.00  154
 23  \w     30.00  69.00   0.50    2.00    --  102.95 -61.00 -90.00   78
 24  \w     30.00  69.00   0.50    2.00    --  102.95 -61.00  30.00   78
 25  \w     36.00 105.00   0.50    2.00    --  102.95 -95.00 -30.00  138
 26  \w     36.00  97.00   0.50    2.00    --  102.95 -77.00 150.00  122
 27  \w     36.00 105.00   0.50    2.00    --  102.95 -95.00   0.00  138
 28  \w     95.00 173.00   0.50    2.00    --  102.95 125.00-180.00  156
 29  \w     30.00  69.00   0.50    2.00    --  102.95 -61.00-180.00   78
 30  \w     30.00  69.00   0.50    2.00    --  102.95 -61.00   0.00   78
 31  \w     79.00 170.00   0.50    2.00    --  102.95  77.00 -90.00  182
 32  \w     89.00 178.00   0.50    2.00    --  102.95  45.00   0.00  178
 33  \w     34.00 111.00   0.50    2.00    --  102.95-125.00 150.00  154
 34  \w     30.00  69.00   0.50    2.00    --  102.95 -61.00 120.00   78
 35  \w     36.00 105.00   0.50    2.00    --  102.95 -95.00 -90.00  138
 36  \w     30.00  69.00   0.50    2.00    --  102.95 -61.00-150.00   78
 37  \w     79.00 170.00   0.50    2.00    --  102.95  77.00 -90.00  182
 38  \w     50.00 178.00   0.50    2.00    --  102.95  15.00 -30.00  256
 39  \w     30.00  69.00   0.50    2.00    --  102.95 -61.00  60.00   78
 40  \w     50.00 178.00   0.50    2.00    --  102.95  15.00 -30.00  256
 41  \w     34.00 111.00   0.50    2.00    --  102.95-125.00 120.00  154
 42  \w     36.00  97.00   0.50    2.00    --  102.95 -77.00-180.00  122
 43  \w     86.00 178.00   0.50    2.00    --  102.95  30.00  60.00  184
 44  \w     86.00 178.00   0.50    2.00    --  102.95  30.00  60.00  184
 45  \w     36.00 105.00   0.50    2.00    --  102.95 -95.00 -60.00  138
 46  \w     36.00 105.00   0.50    2.00    --  102.95 -95.00  90.00  138
 47  \w     89.00 178.00   0.50    2.00    --  102.95  45.00-180.00  178
 48  \w    -52.00 -26.00   0.50    0.50    --   18.00 151.00-126.75   52
 49  \w      8.00  34.00   0.50    0.50    --   42.00  93.00 173.63   52
 50  \w     14.00  43.00   0.50    0.50    --   46.00  90.00-100.36   58
 51  \w     14.00  43.00   0.50    0.50    --   46.00  90.00 125.49   58
 52  \w     40.00 131.00   0.50    0.50    --   62.00  74.00 -68.86  182
 53  \w     38.00 130.00   0.50    0.50    --   62.00  76.00-153.41  184
 54  \w     43.00 134.00   0.50    0.50    --   66.00  75.00 128.74  182
 55  \w   -141.00 -50.00   0.50    0.50    --  -70.00 -67.00-133.82  182
 56  \w   -145.00 -53.00   0.50    0.50    --  -77.84 -77.00  60.00  184
 57  \w   -145.00 -53.00   0.50    0.50    --  -77.84 -77.00 120.00  184
 58  \w   -145.00 -53.00   0.50    0.50    --  -77.84 -77.00 -60.00  184
 59  \w   -145.00 -53.00   0.50    0.50    --  -77.84 -77.00-150.00  184
 60  \w   -153.00 -62.00   0.50    2.00    --  -86.25 -77.00 177.17  182
 61  \w   -154.00 -62.00   0.50    2.00    --  -86.25 -76.00  42.24  184
 62  \w   -153.00 -62.00   0.50    2.00    --  -86.25 -77.00 -76.69  182
 63  \w     89.00 178.00   0.50    2.00    --  102.95  45.00 150.00  178
 64  \w     79.00 170.00   0.50    2.00    --  102.95  77.00 -60.00  182
 65  \w     85.00 118.00   0.50    2.00    --  102.95  61.00-120.00   66
 66  \w     79.00 170.00   0.50    2.00    --  102.95  77.00-150.00  182
 67  \w     79.00 170.00   0.50    2.00    --  102.95  77.00-180.00  182
 68  \w     79.00 170.00   0.50    2.00    --  102.95  77.00  30.00  182
 69  \w     79.00 170.00   0.50    2.00    --  102.95  77.00  60.00  182
 70  \w     79.00 170.00   0.50    2.00    --  102.95  77.00  90.00  182
 71  \w     89.00 178.00   0.50    2.00    --  102.95  45.00 120.00  178
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'XtaLAB Synergy, Dualflex, HyPix-Arc 100'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_type
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      -0.0650511000
_diffrn_orient_matrix_UB_12      -0.0721955000
_diffrn_orient_matrix_UB_13      0.0577713000
_diffrn_orient_matrix_UB_21      0.2069628000
_diffrn_orient_matrix_UB_22      -0.0664107000
_diffrn_orient_matrix_UB_23      0.0186047000
_diffrn_orient_matrix_UB_31      -0.0604270000
_diffrn_orient_matrix_UB_32      0.1939359000
_diffrn_orient_matrix_UB_33      0.0203050000
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0436
_diffrn_reflns_av_unetI/netI     0.0177
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 0.991
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       30
_diffrn_reflns_limit_l_min       -30
_diffrn_reflns_number            55004
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 0.991
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         77.130
_diffrn_reflns_theta_min         3.672
_diffrn_source                   'micro-focus sealed X-ray tube'
_diffrn_source_type              'PhotonJet (Cu) X-ray Source'
_exptl_absorpt_coefficient_mu    2.213
_exptl_absorpt_correction_T_max  1.000
_exptl_absorpt_correction_T_min  0.736
_exptl_absorpt_correction_type   gaussian
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.43.144a (Rigaku Oxford Diffraction, 2024)
Numerical absorption correction based on gaussian integration over
a multifaceted crystal model
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            orange
_exptl_crystal_colour_primary    orange
_exptl_crystal_density_diffrn    1.489
_exptl_crystal_description       plate
_exptl_crystal_F_000             608
_exptl_crystal_size_max          0.129
_exptl_crystal_size_mid          0.121
_exptl_crystal_size_min          0.046
_refine_diff_density_max         0.278
_refine_diff_density_min         -0.439
_refine_diff_density_rms         0.047
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.056
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     381
_refine_ls_number_reflns         5503
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.056
_refine_ls_R_factor_all          0.0357
_refine_ls_R_factor_gt           0.0341
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0481P)^2^+0.5638P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0917
_refine_ls_wR_factor_ref         0.0929
_reflns_Friedel_coverage         0.000
_reflns_number_gt                5203
_reflns_number_total             5503
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5sc08074f2.cif
_cod_data_source_block           080am25jialie_mpsneoviired
_cod_depositor_comments
'Adding full bibliography for 1576602--1576604.cif.'
_cod_database_code               1576604
_shelx_shelxl_version_number     2019/3
_chemical_oxdiff_formula         CHNSO
_chemical_oxdiff_usercomment     'orange plate'
_shelx_estimated_absorpt_t_max   0.905
_shelx_estimated_absorpt_t_min   0.763
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2.a Aromatic/amide H refined with riding coordinates:
 C4(H4), C5(H5), C6(H6), C7(H7), C12(H12), C13(H13), C14(H14), C15(H15),
 C20(H20), C21(H21), C22(H22), C23(H23), C28(H28), C29(H29), C30(H30), C31(H31)
2.b Idealised Me refined as rotating group:
 C2(H2A,H2B,H2C), C18(H18A,H18B,H18C)
;
_shelx_res_checksum              29910
_shelx_hkl_checksum              46811
_ins_header
;
TITL 080AM25Jialie_mPSneoVIIred in P-1 
REM P-1 (#2 in standard setting)
CELL 1.54184   7.626585   7.922528  24.437716  81.1436  82.1159  64.1257
ZERR   19.00   0.000073   0.000106   0.000275   0.0010   0.0009   0.0011
LATT  1
SFAC C H N O S
UNIT 19.00 19.00 19.00 19.00 19.00
REM  CrysAlisPro recorded range (K): Min=150.0; max=150.0; aver:150.0
TEMP -123
SIZE 0.05 0.12 0.13
TREF
HKLF 4
END
;
_olex2_submission_special_instructions 'No special instructions were received'
_oxdiff_exptl_absorpt_empirical_details
;
Empirical correction (ABSPACK) includes:
- Absorption correction using spherical harmonics
- Frame scaling
;
_oxdiff_exptl_absorpt_empirical_full_max 1.485
_oxdiff_exptl_absorpt_empirical_full_min 0.717