Koser's reagent-promoted synthesis of substituted isoxazoles and their photophysical properties.
Budhwan, Rajnish; Dahiya, Pooja; Singh, Nikunj; Chauhan, Shivom; Peddinti, Rama Krishna; Organic & biomolecular chemistry 24 (2026) 2742–2751; doi:10.1039/d5ob02000j

data_7161060
_publ_section_title
;
 Koser's reagent-promoted synthesis of substituted isoxazoles and their
 photophysical properties.
;
_journal_issue                   13
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              2742
_journal_page_last               2751
_journal_paper_doi               10.1039/d5ob02000j
_journal_volume                  24
_journal_year                    2026
_chemical_formula_moiety         'C24 H15 N O4'
_chemical_formula_sum            'C24 H15 N O4'
_chemical_formula_weight         381.37
_space_group_crystal_system      orthorhombic
_space_group_IT_number           19
_space_group_name_Hall           'P 2ac 2ab'
_space_group_name_H-M_alt        'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_audit_creation_date             2026-02-19
_audit_creation_method
;
Olex2 1.5
(compiled 2024.02.16 svn.r378c4104 for OlexSys, GUI svn.r6928)
;
_audit_update_record
;
2026-02-19 deposited with the CCDC.	2026-03-03 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   6.684(3)
_cell_length_b                   13.176(6)
_cell_length_c                   19.701(9)
_cell_measurement_reflns_used    5371
_cell_measurement_temperature    100.00
_cell_measurement_theta_max      24.759
_cell_measurement_theta_min      2.582
_cell_volume                     1735.0(14)
_computing_cell_refinement       'SAINT V8.42 (?, 2016)'
_computing_data_reduction        'SAINT V8.42 (?, 2016)'
_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 2018/2 (Sheldrick, 2018)'
_diffrn_ambient_temperature      100.00
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.991
_diffrn_measurement_device_type  'Bruker D8 QUEST CMOS'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0836
_diffrn_reflns_av_unetI/netI     0.0563
_diffrn_reflns_Laue_measured_fraction_full 0.992
_diffrn_reflns_Laue_measured_fraction_max 0.991
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            21461
_diffrn_reflns_point_group_measured_fraction_full 0.990
_diffrn_reflns_point_group_measured_fraction_max 0.989
_diffrn_reflns_theta_full        25.095
_diffrn_reflns_theta_max         25.095
_diffrn_reflns_theta_min         2.067
_diffrn_source_current           1.4
_diffrn_source_power             0.07
_diffrn_source_voltage           50.0
_exptl_absorpt_coefficient_mu    0.100
_exptl_absorpt_correction_T_max  0.7327
_exptl_absorpt_correction_T_min  0.6589
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.1730 before and 0.0927 after correction.
The Ratio of minimum to maximum transmission is 0.8993.
The \l/2 correction factor is Not present.
;
_exptl_crystal_colour            'clear yellowish'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   yellowish
_exptl_crystal_density_diffrn    1.460
_exptl_crystal_description       block
_exptl_crystal_F_000             792
_exptl_crystal_size_max          0.245
_exptl_crystal_size_mid          0.098
_exptl_crystal_size_min          0.015
_refine_diff_density_max         0.171
_refine_diff_density_min         -0.190
_refine_diff_density_rms         0.049
_refine_ls_abs_structure_details
;
 Flack x determined using 1007 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.1(9)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.081
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     262
_refine_ls_number_reflns         3050
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.081
_refine_ls_R_factor_all          0.0534
_refine_ls_R_factor_gt           0.0454
_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^)+(0.0514P)^2^+0.3189P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1026
_refine_ls_wR_factor_ref         0.1101
_reflns_Friedel_coverage         0.713
_reflns_Friedel_fraction_full    0.987
_reflns_Friedel_fraction_max     0.986
_reflns_number_gt                2689
_reflns_number_total             3050
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5ob02000j3.cif
_cod_data_source_block           rkp_rb_840_2073_a
_cod_depositor_comments
'Adding full bibliography for 7161059--7161061.cif.'
_cod_original_cell_volume        1735.0(13)
_cod_database_code               7161060
_shelx_shelxl_version_number     2019/3
_shelx_estimated_absorpt_t_max   0.998
_shelx_estimated_absorpt_t_min   0.976
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups
2.a Secondary CH2 refined with riding coordinates:
 C7(H7A,H7B)
2.b Aromatic/amide H refined with riding coordinates:
 C2(H2), C3(H3), C4(H4), C5(H5), C6(H6), C9(H9), C10(H10), C12(H12), C13(H13),
 C21(H21), C22(H22), C23(H23), C24(H24)
;
_shelx_res_checksum              51931
_olex2_submission_special_instructions 'No special instructions were received'