Photoinduced [3+2] cycloaddition <i>via</i> HFIP-promoted <i>in situ</i> formation of isobutylene from the Boc group.
Luo, Xue-Ling; Lv, Yu; Luo, Di-Jing; Qin, Lu-Lu; Li, Shu-Hui; Ye, Zhi-Peng; Xie, Zhen-Zhen; Xia, Peng-Ju; Chemical communications (Cambridge, England) 61 (2025) 18180–18183; doi:10.1039/d5cc05303j

data_7135216
_publ_section_title
;
 Photoinduced [3+2] cycloaddition <i>via</i> HFIP-promoted <i>in situ</i>
 formation of isobutylene from the Boc group.
;
_journal_issue                   92
_journal_name_full               'Chemical communications (Cambridge, England)'
_journal_page_first              18180
_journal_page_last               18183
_journal_paper_doi               10.1039/d5cc05303j
_journal_volume                  61
_journal_year                    2025
_chemical_formula_moiety         'C18 H22 O5'
_chemical_formula_sum            'C18 H22 O5'
_chemical_formula_weight         318.35
_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             2025-06-11
_audit_creation_method
;
Olex2 1.2
(compiled 2018.05.29 svn.r3508 for OlexSys, GUI svn.r5506)
;
_audit_update_record
;
2025-06-11 deposited with the CCDC.	2025-10-07 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 95.9610(10)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   8.13450(10)
_cell_length_b                   10.4932(2)
_cell_length_c                   20.2720(3)
_cell_measurement_temperature    500
_cell_volume                     1721.00(5)
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'ShelXL (Sheldrick, 2015)'
_computing_structure_solution    'ShelXT (Sheldrick, 2015)'
_diffrn_ambient_temperature      500
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.957
_diffrn_measurement_device_type  XtaLABSynergy-DS
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0297
_diffrn_reflns_av_unetI/netI     0.0316
_diffrn_reflns_Laue_measured_fraction_full 0.998
_diffrn_reflns_Laue_measured_fraction_max 0.957
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            11501
_diffrn_reflns_point_group_measured_fraction_full 0.998
_diffrn_reflns_point_group_measured_fraction_max 0.957
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         73.022
_diffrn_reflns_theta_min         4.386
_exptl_absorpt_coefficient_mu    0.733
_exptl_absorpt_correction_T_max  500
_exptl_absorpt_correction_T_min  80
_exptl_absorpt_correction_type   analytical
_exptl_absorpt_process_details   a
_exptl_crystal_colour            'clear light colourless'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   light
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.229
_exptl_crystal_description       block
_exptl_crystal_F_000             680
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.4
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.149
_refine_diff_density_min         -0.193
_refine_diff_density_rms         0.040
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.080
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     212
_refine_ls_number_reflns         3284
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.080
_refine_ls_R_factor_all          0.0503
_refine_ls_R_factor_gt           0.0462
_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^)+(0.0700P)^2^+0.1978P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1299
_refine_ls_wR_factor_ref         0.1344
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2845
_reflns_number_total             3284
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5cc05303j2.cif
_cod_data_source_block           20240102-xpj-lxl-167_auto
_cod_database_code               7135216
_shelx_shelxl_version_number     2018/3
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2.a Ternary CH refined with riding coordinates:
 C8(H8)
2.b Secondary CH2 refined with riding coordinates:
 C12(H12A,H12B), C21(H21A,H21B)
2.c Aromatic/amide H refined with riding coordinates:
 C1(H1), C5(H5), C2(H2), C4(H4), C3(H3)
2.d Idealised Me refined as rotating group:
 C10(H10A,H10B,H10C), C11(H11A,H11B,H11C), C16(H16A,H16B,H16C), C18(H18A,H18B,
 H18C)
;
_olex2_submission_special_instructions 'No special instructions were received'