Synthesis of tetrahydrochromenes and dihydronaphthofurans via a cascade process of [3 + 3] and [3 + 2] annulation reactions: mechanistic insight for 6-endo-trig and 5-exo-trig cyclisation
Reddy, Yeruva Pavankumar; Srinivasadesikan, V.; Balamurugan, Rengarajan; Lin, M. C.; Anwar, Shaik; RSC Advances 13 (2023) 5796–5803; doi:10.1039/D2RA08163F

data_7246293
_publ_section_title
;
 Synthesis of tetrahydrochromenes and dihydronaphthofurans via a cascade
 process of [3 + 3] and [3 + 2] annulation reactions: mechanistic insight
 for 6-endo-trig and 5-exo-trig cyclisation
;
_journal_issue                   9
_journal_name_full               'RSC Advances'
_journal_page_first              5796
_journal_page_last               5803
_journal_paper_doi               10.1039/D2RA08163F
_journal_volume                  13
_journal_year                    2023
_chemical_formula_moiety         'C19 H17 N O3'
_chemical_formula_sum            'C19 H17 N O3'
_chemical_formula_weight         307.33
_space_group_crystal_system      orthorhombic
_space_group_IT_number           33
_space_group_name_Hall           'P 2c -2n'
_space_group_name_H-M_alt        'P n a 21'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2018/3
_audit_update_record
;
2022-02-03 deposited with the CCDC.	2023-02-06 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   10.0111(10)
_cell_length_b                   11.7592(12)
_cell_length_c                   13.0970(15)
_cell_measurement_reflns_used    9960
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      29.783
_cell_measurement_theta_min      2.327
_cell_volume                     1541.8(3)
_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    'SHELXT 2018/2 (Sheldrick, 2018)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_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  0.0591
_diffrn_reflns_av_unetI/netI     0.0345
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            28119
_diffrn_reflns_point_group_measured_fraction_full 0.996
_diffrn_reflns_point_group_measured_fraction_max 0.989
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.486
_diffrn_reflns_theta_min         2.328
_diffrn_source                   microfocus
_exptl_absorpt_coefficient_mu    0.090
_exptl_absorpt_correction_T_max  0.7461
_exptl_absorpt_correction_T_min  0.6725
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
 SADABS 2016/2: Krause, L., Herbst-Irmer, R., Sheldrick G.M. & Stalke D.,
 J. Appl. Cryst. 48 (2015) 3-10
;
_exptl_crystal_density_diffrn    1.324
_exptl_crystal_description       BLOCK
_exptl_crystal_F_000             648
_exptl_crystal_size_max          0.340
_exptl_crystal_size_mid          0.320
_exptl_crystal_size_min          0.280
_refine_diff_density_max         0.167
_refine_diff_density_min         -0.162
_refine_diff_density_rms         0.036
_refine_ls_abs_structure_details
;
 Flack x determined using 1314 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.4(4)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.039
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     208
_refine_ls_number_reflns         3504
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.039
_refine_ls_R_factor_all          0.0418
_refine_ls_R_factor_gt           0.0365
_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^)+(0.0528P)^2^+0.1574P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0947
_refine_ls_wR_factor_ref         0.0985
_reflns_Friedel_coverage         0.896
_reflns_Friedel_fraction_full    0.992
_reflns_Friedel_fraction_max     0.978
_reflns_number_gt                3158
_reflns_number_total             3504
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d2ra08163f2.cif
_cod_data_source_block           KB100_0m
_cod_database_code               7246293
_shelx_shelxl_version_number     2018/3
_shelx_estimated_absorpt_t_min   0.970
_shelx_estimated_absorpt_t_max   0.975
_shelx_res_checksum              86135