DBU-catalyzed annulation strategy for modular assembly of 2,3-difunctionalized dihydrobenzofurans.
Yuan, Lili; Wang, Jie; Tang, Qiang; Wang, Yiping; Ma, Beibei; Shang, Yongjia; He, Xinwei; Organic & biomolecular chemistry 23 (2025) 1832–1836; doi:10.1039/d4ob01406e

data_7160334
_publ_section_title
;
 DBU-catalyzed annulation strategy for modular assembly of
 2,3-difunctionalized dihydrobenzofurans.
;
_journal_issue                   8
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              1832
_journal_page_last               1836
_journal_paper_doi               10.1039/d4ob01406e
_journal_volume                  23
_journal_year                    2025
_chemical_formula_moiety         'C18 H17 N O4'
_chemical_formula_sum            'C18 H17 N O4'
_chemical_formula_weight         311.32
_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
_atom_sites_solution_secondary   difmap
_audit_creation_date             2024-05-20
_audit_creation_method
;
Olex2 1.5
(compiled 2022.04.07 svn.rca3783a0 for OlexSys, GUI svn.r6498)
;
_audit_update_record
;
2024-08-19 deposited with the CCDC.	2025-01-10 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 107.7360(10)
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   26.440(2)
_cell_length_b                   7.9493(7)
_cell_length_c                   15.9676(13)
_cell_measurement_reflns_used    6529
_cell_measurement_temperature    293.15(10)
_cell_measurement_theta_max      27.575
_cell_measurement_theta_min      2.394
_cell_volume                     3196.5(5)
_computing_cell_refinement       'SAINT v7.34A (Bruker, 200?)'
_computing_data_collection       'Bruker SMART APEX II diffractometer'
_computing_data_reduction        'SAINT v7.34A (Bruker, 200?)'
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2019/3 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT  (Sheldrick, 2015)'
_diffrn_ambient_temperature      293.15(10)
_diffrn_detector                 'CCD area detector'
_diffrn_detector_area_resol_mean 7.9
_diffrn_detector_type            'CCD area detector'
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device       'three-circle diffractometer'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0248
_diffrn_reflns_av_unetI/netI     0.0212
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.993
_diffrn_reflns_limit_h_max       33
_diffrn_reflns_limit_h_min       -34
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            13429
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.993
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.642
_diffrn_reflns_theta_min         1.617
_diffrn_source                   'sealed X-ray tube'
_diffrn_source_current           30.0
_diffrn_source_power             1.5
_diffrn_source_target            Mo
_diffrn_source_voltage           50.0
_exptl_absorpt_coefficient_mu    0.092
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.6539
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.0911 before and 0.0370 after correction.
The Ratio of minimum to maximum transmission is 0.8770.
The \l/2 correction factor is Not present.
;
_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    1.294
_exptl_crystal_description       block
_exptl_crystal_F_000             1312
_exptl_crystal_size_max          0.14
_exptl_crystal_size_mid          0.13
_exptl_crystal_size_min          0.11
_refine_diff_density_max         0.195
_refine_diff_density_min         -0.191
_refine_diff_density_rms         0.040
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.052
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     209
_refine_ls_number_reflns         3708
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.052
_refine_ls_R_factor_all          0.0584
_refine_ls_R_factor_gt           0.0471
_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^)+(0.0752P)^2^+1.2970P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1350
_refine_ls_wR_factor_ref         0.1464
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2959
_reflns_number_total             3708
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d4ob01406e2.cif
_cod_data_source_block           131202b_0m
_cod_depositor_comments          'Adding full bibliography for 7160334.cif.'
_cod_database_code               7160334
_shelx_shelxl_version_number     2019/3
_shelx_estimated_absorpt_t_max   0.990
_shelx_estimated_absorpt_t_min   0.987
_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 Riding coordinates:
 C18(H18A,H18B,H18C)
2.b Ternary CH refined with riding coordinates:
 C1(H1), C2(H2)
2.c Secondary CH2 refined with riding coordinates:
 C9(H9A,H9B)
2.d Aromatic/amide H refined with riding coordinates:
 C4(H4), C6(H6), C7(H7), C13(H13), C14(H14), C16(H16), C17(H17)
2.e Idealised Me refined as rotating group:
 C10(H10A,H10B,H10C)
;
_shelx_res_checksum              10612
_olex2_submission_special_instructions 'No special instructions were received'