Continuous flow synthesis of cyclobutenes via lithium ynolates
Kohyama, Aki; Namioka, Motoki; Naka, Hiroshi; Ashikari, Yosuke; Nagaki, Aiichiro; Takikawa, Hiroshi; Yamaoka, Yousuke; Takasu, Kiyosei; Green Chemistry 27 (2025) 2760–2765; doi:10.1039/D4GC05102E

data_7249937
_publ_section_title
;
 Continuous flow synthesis of cyclobutenes via lithium ynolates
;
_journal_issue                   10
_journal_name_full               'Green Chemistry'
_journal_page_first              2760
_journal_page_last               2765
_journal_paper_doi               10.1039/D4GC05102E
_journal_volume                  27
_journal_year                    2025
_chemical_absolute_configuration unk
_chemical_formula_moiety         'C21 H26 O5'
_chemical_formula_sum            'C21 H26 O5'
_chemical_formula_weight         358.42
_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             2024-12-13
_audit_creation_method
;
Olex2 1.3-ac4
(compiled 2020.11.27 svn.r5f609507 for Rigaku Oxford Diffraction, GUI svn.r6214)
;
_audit_update_record
;
2024-12-23 deposited with the CCDC.	2025-02-11 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   5.52413(13)
_cell_length_b                   15.2460(4)
_cell_length_c                   22.0591(6)
_cell_measurement_reflns_used    10336
_cell_measurement_temperature    93
_cell_measurement_theta_max      72.0060
_cell_measurement_theta_min      3.4990
_cell_volume                     1857.84(8)
_computing_cell_refinement       'CrysAlisPro 1.171.41.122a (Rigaku OD, 2021)'
_computing_data_collection       'CrysAlisPro 1.171.41.122a (Rigaku OD, 2021)'
_computing_data_reduction        'CrysAlisPro 1.171.41.122a (Rigaku OD, 2021)'
_computing_molecular_graphics    'Olex2 1.3-ac4 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.3-ac4 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2018/3 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT  (Sheldrick, 2015)'
_diffrn_ambient_temperature      93
_diffrn_detector                 'Hybrid Pixel Array Detector'
_diffrn_detector_area_resol_mean 5.8140
_diffrn_detector_type            'Rigaku Saturn724+'
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.988
_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   -136.00  42.00   0.50    0.50    --  -46.90  11.00  -3.00  356
  2  \w   -187.00  -8.00   0.50    0.96    --  -97.40  11.00  -3.00  358
  3  \w    -84.00 -26.00   0.50    0.50    --    5.00  50.00 120.00  116
  4  \w    -84.00 -38.00   0.50    0.50    --    5.00  60.00  60.00   92
  5  \w    -84.00 -38.00   0.50    0.50    --    5.00  60.00  30.00   92
  6  \w     14.00  42.00   0.50    0.50    --  -46.90  46.00 142.68   56
  7  \w   -187.00 -14.00   0.50    0.96    --  -97.40  46.00  18.66  346
  8  \w   -187.00 -36.00   0.50    0.96    --  -97.40  58.00 113.93  302
  9  \w   -187.00 -35.00   0.50    0.96    --  -97.40  57.00 140.28  304
 10  \w   -187.00 -36.00   0.50    0.96    --  -97.40  58.00 177.32  302
 11  \w   -187.00  -8.00   0.50    0.96    --  -97.40  40.00  60.00  358
 12  \w   -186.00 -50.00   0.50    0.96    --  -97.40  60.00  90.33  272
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'XtaLAB AFC11 (RCD3): quarter-chi single'
_diffrn_measurement_method       '\w scans'
_diffrn_measurement_specimen_support 'Mitegen 50um'
_diffrn_orient_matrix_type
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      0.0034559000
_diffrn_orient_matrix_UB_12      -0.0851519000
_diffrn_orient_matrix_UB_13      0.0376748000
_diffrn_orient_matrix_UB_21      0.0548551000
_diffrn_orient_matrix_UB_22      -0.0530632000
_diffrn_orient_matrix_UB_23      -0.0577493000
_diffrn_orient_matrix_UB_31      0.2735087000
_diffrn_orient_matrix_UB_32      0.0117129000
_diffrn_orient_matrix_UB_33      0.0110882000
_diffrn_radiation_collimation    0.3
_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  0.0615
_diffrn_reflns_av_unetI/netI     0.0379
_diffrn_reflns_Laue_measured_fraction_full 0.996
_diffrn_reflns_Laue_measured_fraction_max 0.988
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -4
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            16572
_diffrn_reflns_point_group_measured_fraction_full 0.997
_diffrn_reflns_point_group_measured_fraction_max 0.986
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         72.318
_diffrn_reflns_theta_min         3.524
_diffrn_source                   'Rotating-anode X-ray tube'
_diffrn_source_current           24.0
_diffrn_source_power             1.2
_diffrn_source_target            Mo
_diffrn_source_type              'Rigaku (Cu) X-ray Source'
_diffrn_source_voltage           50.0
_exptl_absorpt_coefficient_mu    0.737
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.63370
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.41.122a (Rigaku Oxford Diffraction, 2021)
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    1.281
_exptl_crystal_description       needle
_exptl_crystal_F_000             768
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.03
_refine_diff_density_max         0.224
_refine_diff_density_min         -0.190
_refine_diff_density_rms         0.038
_refine_ls_abs_structure_details
;
 Flack x determined using 1359 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   -0.04(12)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.092
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     238
_refine_ls_number_reflns         3606
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.092
_refine_ls_R_factor_all          0.0379
_refine_ls_R_factor_gt           0.0361
_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^)+(0.0570P)^2^+0.2480P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0975
_refine_ls_wR_factor_ref         0.0983
_reflns_Friedel_coverage         0.705
_reflns_Friedel_fraction_full    0.999
_reflns_Friedel_fraction_max     0.982
_reflns_number_gt                3393
_reflns_number_total             3606
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d4gc05102e2.cif
_cod_data_source_block           241213ak2_auto
_cod_depositor_comments          'Adding full bibliography for 7249937.cif.'
_cod_original_cell_volume        1857.83(8)
_cod_database_code               7249937
_shelx_shelxl_version_number     2018/3
_chemical_oxdiff_formula         C21H26O5
_shelx_estimated_absorpt_t_max   0.978
_shelx_estimated_absorpt_t_min   0.867
_reflns_odcompleteness_completeness 99.60
_reflns_odcompleteness_iscentric 1
_reflns_odcompleteness_theta     66.97
_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:
 C1(H1), C3(H3), C6(H6)
2.b Secondary CH2 refined with riding coordinates:
 C2(H2A,H2B), C22(H22A,H22B), C25(H25A,H25B), C23(H23A,H23B), C24(H24A,H24B)
2.c Aromatic/amide H refined with riding coordinates:
 C13(H13), C10(H10), C11(H11), C14(H14)
2.d Idealised Me refined as rotating group:
 C20(H20A,H20B,H20C), C16(H16A,H16B,H16C), C26(H26A,H26B,H26C)
;
_shelx_res_checksum              52162
_shelx_hkl_checksum              87878
_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 1.865
_oxdiff_exptl_absorpt_empirical_full_min 0.445