N-Heterocyclic carbene (NHC)-catalyzed tandem imine umpolung-aza-Michael addition-oxidation of β-carboline cyclic imines.
Satyam, Killari; Harish, Battu; Nanubolu, Jagadeesh Babu; Suresh, Surisetti; Chemical communications (Cambridge, England) 56 (2020) 2803–2806; doi:10.1039/d0cc00321b

data_7125865
_publ_section_title
;
 N-Heterocyclic carbene (NHC)-catalyzed tandem imine umpolung-aza-Michael
 addition-oxidation of \b-carboline cyclic imines.
;
_journal_issue                   18
_journal_name_full               'Chemical communications (Cambridge, England)'
_journal_page_first              2803
_journal_page_last               2806
_journal_paper_doi               10.1039/d0cc00321b
_journal_volume                  56
_journal_year                    2020
_chemical_formula_moiety         'C15 H16 N2 O3'
_chemical_formula_sum            'C15 H16 N2 O3'
_chemical_formula_weight         272.30
_chemical_name_systematic
'Methyl 3-(1-oxo-1,3,4,9-tetrahydro-2H-pyrido[3,4-b]indol-2-yl)propanoate'
_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   mixed
_audit_creation_method           SHELXL-2018/3
_audit_update_record
;
2019-09-13 deposited with the CCDC.	2020-01-23 downloaded from the CCDC.
;
_cell_angle_alpha                90
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_cell_angle_gamma                90
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_cell_length_c                   17.896(7)
_cell_measurement_reflns_used    7286
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      30.196
_cell_measurement_theta_min      2.280
_cell_volume                     1365.6(12)
_computing_cell_refinement       '<i>SAINT</i> (Bruker, 2016)'
_computing_data_collection       '<i>APEX3</i> (Bruker, 2016)'
_computing_data_reduction        'Bruker SAINT'
_computing_structure_refinement  'SHELXL-2018/3 (Sheldrick, 2018)'
_computing_structure_solution    '<i>SHELXT</i> (Sheldrick, 2015)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Bruker D8 QUEST PHOTON-100'
_diffrn_measurement_method       '\w and \f'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0435
_diffrn_reflns_av_unetI/netI     0.0375
_diffrn_reflns_Laue_measured_fraction_full 0.997
_diffrn_reflns_Laue_measured_fraction_max 0.997
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            12066
_diffrn_reflns_point_group_measured_fraction_full 0.997
_diffrn_reflns_point_group_measured_fraction_max 0.997
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.998
_diffrn_reflns_theta_min         2.281
_exptl_absorpt_coefficient_mu    0.093
_exptl_absorpt_correction_T_max  0.7461
_exptl_absorpt_correction_T_min  0.7028
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS 2014/5'
_exptl_crystal_density_diffrn    1.324
_exptl_crystal_description       needle
_exptl_crystal_F_000             576
_exptl_crystal_recrystallization_method
'Re-crystallisation from solvent: Ethanol/Acetonitrile (1:2)'
_exptl_crystal_size_max          0.400
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_exptl_crystal_size_min          0.260
_refine_diff_density_max         0.207
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_refine_diff_density_rms         0.044
_refine_ls_extinction_method     none
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_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     196
_refine_ls_number_reflns         2684
_refine_ls_number_restraints     6
_refine_ls_restrained_S_all      1.058
_refine_ls_R_factor_all          0.0603
_refine_ls_R_factor_gt           0.0493
_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^)+(0.0631P)^2^+0.6395P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1343
_refine_ls_wR_factor_ref         0.1429
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2210
_reflns_number_total             2684
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d0cc00321b2.cif
_cod_data_source_block           KA270_0m-auto
_cod_depositor_comments          'Adding full bibliography for 7125865.cif.'
_cod_original_cell_volume        1365.6(11)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               7125865
_shelx_shelxl_version_number     2018/3
_shelx_estimated_absorpt_t_min   0.964
_shelx_estimated_absorpt_t_max   0.976
_shelx_res_checksum              68234