Acid-induced rearrangements of polycyclic β-hydroxy acids and their esters.
Tkachenko, Ilya M.; Nezamutdinova, Kamila R.; Gladarenko, Vladislav A.; Aksenov, Nicolai A.; Klimochkin, Yuri N.; Organic & biomolecular chemistry 24 (2026) 1620–1633; doi:10.1039/d5ob02012c

data_7160964
_publ_section_title
;
 Acid-induced rearrangements of polycyclic &#x3b2;-hydroxy acids and their
 esters.
;
_journal_issue                   8
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              1620
_journal_page_last               1633
_journal_paper_doi               10.1039/d5ob02012c
_journal_volume                  24
_journal_year                    2026
_chemical_formula_moiety         'C12 H18 O2'
_chemical_formula_sum            'C12 H18 O2'
_chemical_formula_weight         194.26
_chemical_name_systematic
'2-(1,5,5-trimethylbicyclo[2.2.1]heptan-2-ylidene)acetic acid'
_space_group_crystal_system      monoclinic
_space_group_IT_number           15
_space_group_name_Hall           '-C 2yc'
_space_group_name_H-M_alt        'C 1 2/c 1'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     dual
_audit_creation_date             2025-03-01
_audit_creation_method
;
Olex2 1.5
(compiled 2024.02.16 svn.r378c4104 for OlexSys, GUI svn.r6928)
;
_audit_update_record
;
2025-03-01 deposited with the CCDC.	2026-01-30 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 98.3898(13)
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   22.7467(3)
_cell_length_b                   7.33436(11)
_cell_length_c                   13.43652(16)
_cell_measurement_reflns_used    9885
_cell_measurement_temperature    100.01(11)
_cell_measurement_theta_max      75.5600
_cell_measurement_theta_min      6.3490
_cell_volume                     2217.66(5)
_computing_cell_refinement       'CrysAlisPro 1.171.43.90 (Rigaku OD, 2023)'
_computing_data_collection
'CrysAlisPro system (CCD 43.90 64-bit (release 15-09-2023))'
_computing_data_reduction        'CrysAlisPro 1.171.43.90 (Rigaku OD, 2023)'
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2018/3 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT  (Sheldrick, 2015)'
_diffrn_ambient_environment      N~2~
_diffrn_ambient_temperature      100.01(11)
_diffrn_detector                 'CCD plate'
_diffrn_detector_area_resol_mean 5.2529
_diffrn_detector_type            AtlasS2
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.999
_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    -82.00  14.00   1.00    1.00    --  -41.35 104.00  14.00   96
  2  \w      7.00  84.00   1.00    1.00    --   41.35-104.00 -86.00   77
  3  \w     34.00 108.00   1.00    2.50    --  112.00-104.00 -86.00   74
  4  \w    104.00 178.00   1.00    2.50    --  112.00 104.00  14.00   74
  5  \w    -33.00  66.00   1.00    1.00    --   41.35 -38.00 150.00   99
  6  \w      6.00  32.00   1.00    1.00    --   41.35  85.00-130.41   26
  7  \w      7.00  33.00   1.00    1.00    --   41.35  84.00 -99.73   26
  8  \w      7.00  34.00   1.00    1.00    --   41.35  83.00-176.51   27
  9  \w     27.00  95.00   1.00    1.00    --   41.35-125.00 120.00   68
 10  \w     83.00 178.00   1.00    2.50    --  112.00  61.00  60.00   95
 11  \w    104.00 178.00   1.00    2.50    --  112.00 111.00 150.00   74
 12  \w     40.00 141.00   1.00    2.50    --  112.00 -61.00-120.00  101
 13  \w     31.00 159.00   1.00    2.50    --  112.00 -17.00 -14.15  128
 14  \w     39.00 109.00   1.00    2.50    --  112.00-111.00 150.00   70
 15  \w    103.00 178.00   1.00    2.50    --  112.00  77.00  30.00   75
 16  \w     83.00 178.00   1.00    2.50    --  112.00  61.00  60.00   95
 17  \w     40.00 141.00   1.00    2.50    --  112.00 -61.00-120.00  101
 18  \w    104.00 178.00   1.00    2.50    --  112.00 111.00  90.00   74
 19  \w    103.00 178.00   1.00    2.50    --  112.00  77.00-120.00   75
 20  \w     33.00 146.00   1.00    2.50    --  112.00 -82.00 175.22  113
 21  \w     33.00 146.00   1.00    2.50    --  112.00 -82.00 175.22  113
 22  \w     61.00 146.00   1.00    2.50    --  112.00 178.00  90.00   85
 23  \w     36.00 145.00   1.00    2.50    --  112.00 -77.00 -90.00  109
 24  \w     84.00 178.00   1.00    2.50    --  112.00  30.00-120.00   94
 25  \w     39.00 109.00   1.00    2.50    --  112.00-111.00  60.00   70
 26  \w     31.00 159.00   1.00    2.50    --  112.00 -17.00 -14.15  128
 27  \w    103.00 178.00   1.00    2.50    --  112.00  77.00 -90.00   75
 28  \w     30.00  89.00   1.00    2.50    --  112.00 -95.00 -30.00   59
 29  \w     30.00 106.00   1.00    2.50    --  112.00 -95.00 150.00   76
 30  \w     30.00  89.00   1.00    2.50    --  112.00 -95.00 -30.00   59
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'SuperNova, Dual, Cu at home/near, AtlasS2'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_type
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      0.0418130000
_diffrn_orient_matrix_UB_12      0.1626496000
_diffrn_orient_matrix_UB_13      -0.0079784000
_diffrn_orient_matrix_UB_21      0.0538646000
_diffrn_orient_matrix_UB_22      -0.1201395000
_diffrn_orient_matrix_UB_23      0.0400633000
_diffrn_orient_matrix_UB_31      0.0061340000
_diffrn_orient_matrix_UB_32      -0.0563454000
_diffrn_orient_matrix_UB_33      -0.1085291000
_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  0.0378
_diffrn_reflns_av_unetI/netI     0.0211
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       28
_diffrn_reflns_limit_h_min       -28
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            16167
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         76.152
_diffrn_reflns_theta_min         3.929
_diffrn_source                   'micro-focus sealed X-ray tube'
_diffrn_source_type              'SuperNova (Cu) X-ray Source'
_exptl_absorpt_coefficient_mu    0.613
_exptl_absorpt_correction_T_max  0.923
_exptl_absorpt_correction_T_min  0.835
_exptl_absorpt_correction_type   analytical
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.43.90 (Rigaku Oxford Diffraction, 2023)
Analytical numeric absorption correction using a multifaceted crystal
model based on expressions derived by R.C. Clark & J.S. Reid.
(Clark, R. C. & Reid, J. S. (1995). Acta Cryst. A51, 887-897)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_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    1.164
_exptl_crystal_description       prism
_exptl_crystal_F_000             848
_exptl_crystal_recrystallization_method 'by slow evaporation of EtOAc solution'
_exptl_crystal_size_max          0.37
_exptl_crystal_size_mid          0.32
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.255
_refine_diff_density_min         -0.247
_refine_diff_density_rms         0.043
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.071
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     209
_refine_ls_number_reflns         2309
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.071
_refine_ls_R_factor_all          0.0498
_refine_ls_R_factor_gt           0.0484
_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^)+(0.0772P)^2^+1.1135P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1333
_refine_ls_wR_factor_ref         0.1350
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2215
_reflns_number_total             2309
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5ob02012c2.cif
_cod_data_source_block           anna_samr1_3
_cod_depositor_comments          'Adding full bibliography for 7160964.cif.'
_cod_database_code               7160964
_shelx_shelxl_version_number     2018/3
_chemical_oxdiff_formula         'C11 H10 N O'
_shelx_estimated_absorpt_t_max   0.914
_shelx_estimated_absorpt_t_min   0.805
_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, All C(H,H,H,H,H,H) groups
2. Others
 Sof(H5BD)=Sof(H5BE)=Sof(H5BF)=Sof(C14)=Sof(C15)=Sof(H15A)=Sof(H15B)=Sof(H15C)=
 Sof(C16)=Sof(H16A)=Sof(H16B)=Sof(H16C)=Sof(C17)=Sof(H17)=Sof(C18)=Sof(H18A)=
 Sof(H18B)=Sof(C20)=Sof(H20A)=Sof(H20B)=Sof(C13)=Sof(C19)=Sof(H19A)=Sof(H19B)=1-
 FVAR(1)
 Sof(C9)=Sof(H9A)=Sof(H9B)=Sof(C4)=Sof(C7)=Sof(H7A)=Sof(H7B)=Sof(C12)=
 Sof(H12A)=Sof(H12B)=Sof(H12C)=Sof(C8)=Sof(H8)=Sof(C11)=Sof(H11A)=Sof(H11B)=
 Sof(H11C)=Sof(C10)=Sof(C6)=Sof(H6A)=Sof(H6B)=Sof(H5AA)=Sof(H5AB)=Sof(H5AC)=
 FVAR(1)
3.a Ternary CH refined with riding coordinates:
 C8(H8), C17(H17)
3.b Secondary CH2 refined with riding coordinates:
 C9(H9A,H9B), C7(H7A,H7B), C6(H6A,H6B), C18(H18A,H18B), C20(H20A,H20B),
 C19(H19A,H19B)
3.c Aromatic/amide H refined with riding coordinates:
 C2(H2)
3.d Idealised Me refined as rotating group:
 C12(H12A,H12B,H12C), C11(H11A,H11B,H11C), C5(H5AA,H5AB,H5AC), C5(H5BD,H5BE,
 H5BF), C15(H15A,H15B,H15C), C16(H16A,H16B,H16C)
;
_shelx_res_checksum              647
_olex2_exptl_crystal_mounting_method
'mounted by acrylic glue on the glass stick'
_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
- Detector area scaling
;
_oxdiff_exptl_absorpt_empirical_full_max 1.744
_oxdiff_exptl_absorpt_empirical_full_min 0.650