Generation and trapping of electron-deficient 1,2-cyclohexadienes. Unexpected hetero-Diels-Alder reactivity.
Wang, Baolei; Constantin, Marius-Georgian; Singh, Simarpreet; Zhou, Yuqiao; Davis, Rebecca L.; West, F. G.; Organic & biomolecular chemistry 19 (2021) 399–405; doi:10.1039/d0ob02285c

data_7157756
_publ_section_title
;
 Generation and trapping of electron-deficient 1,2-cyclohexadienes.
 Unexpected hetero-Diels-Alder reactivity.
;
_journal_issue                   2
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              399
_journal_page_last               405
_journal_paper_doi               10.1039/d0ob02285c
_journal_volume                  19
_journal_year                    2021
_chemical_formula_moiety         'C23 H29 N O2'
_chemical_formula_sum            'C23 H29 N O2'
_chemical_formula_weight         351.47
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_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_atom_sites_solution_hydrogens   mixed
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_audit_creation_method           SHELXL-2017/1
_audit_update_record
;
2020-07-20 deposited with the CCDC.	2020-11-20 downloaded from the CCDC.
;
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_cell_measurement_theta_min      3.06
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_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           CuK\a
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'Re-crystallisation from solvent: Et2O, EtOAc'
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_refine_ls_extinction_method     none
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_refine_ls_restrained_S_all      1.103
_refine_ls_R_factor_all          0.0455
_refine_ls_R_factor_gt           0.0430
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_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0673P)^2^+0.4530P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1260
_refine_ls_wR_factor_ref         0.1286
_reflns_Friedel_coverage         0.000
_reflns_number_gt                3560
_reflns_number_total             3902
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d0ob02285c3.cif
_cod_data_source_block           fgw1903
_cod_depositor_comments
'Adding full bibliography for 7157754--7157756.cif.'
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               7157756
_shelx_shelxl_version_number     2017/1
_shelx_estimated_absorpt_t_min   0.813
_shelx_estimated_absorpt_t_max   0.861
_shelx_res_checksum              76414