Titanocene(III)-Mediated 5-exo-trig Radical Cyclization: En Route to Spirooxindole-Based Tetrahydrofuran and Bicyclic Lactone.
Nallasivam, Jothi Lakshmi; Chakraborty, Tushar Kanti; The Journal of organic chemistry 84 (2019) 16124–16138; doi:10.1021/acs.joc.9b02608

data_4037632
_publ_section_title
;
 Titanocene(III)-Mediated 5-exo-trig Radical Cyclization: En Route to
 Spirooxindole-Based Tetrahydrofuran and Bicyclic Lactone.
;
_journal_issue                   24
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              16124
_journal_page_last               16138
_journal_paper_doi               10.1021/acs.joc.9b02608
_journal_volume                  84
_journal_year                    2019
_chemical_absolute_configuration rm
_chemical_formula_moiety         'C18 H19 N O4'
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_space_group_crystal_system      monoclinic
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_cell_length_a                   5.757(4)
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_cell_length_c                   11.539(7)
_cell_measurement_reflns_used    9703
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      30.16
_cell_measurement_theta_min      3.61
_cell_volume                     788.3(9)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'PLATON (Spek A.L.,2003 '
_computing_publication_material  'WinGX publication routines (Farrugia, 2012)'
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_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_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  0.0210
_diffrn_reflns_av_unetI/netI     0.0114
_diffrn_reflns_Laue_measured_fraction_full 0.998
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_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -16
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_diffrn_reflns_point_group_measured_fraction_full 0.998
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_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         30.560
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_diffrn_source                   'rotating-anode X-ray tube'
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_exptl_absorpt_correction_type   multi-scan
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_exptl_crystal_colour            yellow
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_refine_diff_density_min         -0.142
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_refine_ls_abs_structure_details
; 
 Flack x determined using 2011 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259). 
;
_refine_ls_abs_structure_Flack   -0.19(14)
_refine_ls_extinction_method     none
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_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
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_refine_ls_number_reflns         4830
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.039
_refine_ls_R_factor_all          0.0378
_refine_ls_R_factor_gt           0.0347
_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^)+(0.0643P)^2^+0.0260P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0960
_refine_ls_wR_factor_ref         0.0990
_reflns_Friedel_coverage         0.917
_reflns_Friedel_fraction_full    0.999
_reflns_Friedel_fraction_max     0.997
_reflns_number_gt                4480
_reflns_number_total             4830
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            jo9b02608_si_003.cif
_cod_data_source_block           shelx
_cod_depositor_comments
'Adding full bibliography for 4037631--4037632.cif.'
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               4037632
_shelx_estimated_absorpt_t_min   0.981
_shelx_estimated_absorpt_t_max   0.991
_shelx_res_checksum              26503
_shelx_hkl_checksum              32307