Synthesis of Nonracemic 1,4-Benzoxazines via Ring Opening/Cyclization of Activated Aziridines with 2-Halophenols: Formal Synthesis of Levofloxacin.
Mal, Abhijit; Wani, Imtiyaz Ahmad; Goswami, Gaurav; Ghorai, Manas K.; The Journal of organic chemistry 83 (2018) 7907–7918; doi:10.1021/acs.joc.8b00788

data_4035608
_publ_section_title
;
 Synthesis of Nonracemic 1,4-Benzoxazines via Ring Opening/Cyclization of
 Activated Aziridines with 2-Halophenols: Formal Synthesis of
 Levofloxacin.
;
_journal_issue                   15
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              7907
_journal_page_last               7918
_journal_paper_doi               10.1021/acs.joc.8b00788
_journal_volume                  83
_journal_year                    2018
_chemical_formula_moiety         'C17 H17 N O3 S'
_chemical_formula_sum            'C17 H17 N O3 S'
_chemical_formula_weight         315.37
_space_group_crystal_system      monoclinic
_space_group_IT_number           9
_space_group_name_Hall           'C -2yc'
_space_group_name_H-M_alt        'C 1 c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_audit_creation_date             2017-12-30
_audit_creation_method
;
Olex2 1.2-alpha
(compiled 2017.08.10 svn.r3458 for OlexSys, GUI svn.r5381)
;
_cell_angle_alpha                90
_cell_angle_beta                 116.980(3)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   15.6050(18)
_cell_length_b                   12.3062(14)
_cell_length_c                   9.1044(10)
_cell_measurement_reflns_used    2767
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      25.1
_cell_measurement_theta_min      2.21
_cell_volume                     1558.1(3)
_computing_cell_refinement       'SAINT v6.45A (Bruker, 2003)'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'SAINT v6.45A (Bruker, 2003)'
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'ShelXL (Sheldrick, 2015)'
_computing_structure_solution    'ShelXT (Sheldrick, 2015)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0534
_diffrn_reflns_av_unetI/netI     0.0675
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       18
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            9533
_diffrn_reflns_point_group_measured_fraction_full 0.996
_diffrn_reflns_point_group_measured_fraction_max 0.996
_diffrn_reflns_theta_full        25.101
_diffrn_reflns_theta_max         25.10
_diffrn_reflns_theta_min         2.21
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    0.220
_exptl_absorpt_correction_T_max  0.949
_exptl_absorpt_correction_T_min  0.887
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details
;
SADABS v.2.10 (Bruker,2003) was used for absorption correction.
R(int) was 0.0678 before and 0.0430 after correction.
The Ratio of minimum to maximum transmission is 0.2956.
The \l/2 correction factor is 0.0015.
;
_exptl_crystal_colour            WHITE
_exptl_crystal_density_diffrn    1.344
_exptl_crystal_description       block
_exptl_crystal_F_000             664
_exptl_crystal_size_max          0.55
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.361
_refine_diff_density_min         -0.225
_refine_diff_density_rms         0.046
_refine_ls_abs_structure_details
;
 Flack x determined using 745 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.09(5)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.029
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     200
_refine_ls_number_reflns         2767
_refine_ls_number_restraints     2
_refine_ls_restrained_S_all      1.029
_refine_ls_R_factor_all          0.0894
_refine_ls_R_factor_gt           0.0513
_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^)+(0.0600P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1034
_refine_ls_wR_factor_ref         0.1165
_reflns_Friedel_coverage         0.991
_reflns_Friedel_fraction_full    0.994
_reflns_Friedel_fraction_max     0.994
_reflns_number_gt                1951
_reflns_number_total             2767
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            jo8b00788_si_002.cif
_cod_data_source_block           6deca_0m
_cod_database_code               4035608
_shelx_shelxl_version_number     2016/6
_shelx_estimated_absorpt_t_max   0.96
_shelx_estimated_absorpt_t_min   0.88
_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 Ternary CH refined with riding coordinates:
 C008(H008)
2.b Secondary CH2 refined with riding coordinates:
 C00G(H00A,H00G)
2.c Aromatic/amide H refined with riding coordinates:
 C007(H007), C00B(H00B), C00C(H00C), C00D(H00D), C00E(H00E), C00F(H00F),
 C00H(H00H), C00J(H00J), C00K(H00K)
2.d X=CH2 refined with riding coordinates:
 C00L(H00I,H00L)
2.e Idealised Me refined as rotating group:
 C00M(H00M,H00N,H00O)
;
_shelx_res_checksum              18269
_shelx_hkl_checksum              97518
_olex2_submission_special_instructions 'No special instructions were received'