The Acid and/or Thermal Mediated Ring Contraction of 4H-1,2,6-Thiadiazines To Afford 1,2,5-Thiadiazoles.
Kalogirou, Andreas S.; Kourtellaris, Andreas; Koutentis, Panayiotis A.; Organic letters 18 (2016) 4056–4059; doi:10.1021/acs.orglett.6b01929

data_1543767
_publ_section_title
;
 The Acid and/or Thermal Mediated Ring Contraction of
 4H-1,2,6-Thiadiazines To Afford 1,2,5-Thiadiazoles.
;
_journal_issue                   16
_journal_name_full               'Organic letters'
_journal_page_first              4056
_journal_page_last               4059
_journal_paper_doi               10.1021/acs.orglett.6b01929
_journal_volume                  18
_journal_year                    2016
_chemical_formula_moiety         'C21 H14 N2 O2 S'
_chemical_formula_sum            'C21 H14 N2 O2 S'
_chemical_formula_weight         358.40
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 101.767(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   13.5638(4)
_cell_length_b                   6.3615(2)
_cell_length_c                   20.0924(7)
_cell_measurement_reflns_used    4259
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      72.5890
_cell_measurement_theta_min      5.0030
_cell_volume                     1697.26(10)
_computing_cell_refinement       'CrysAlis RED'
_computing_data_collection       'CrysAlis CCD'
_computing_data_reduction        'CrysAlis RED'
_computing_molecular_graphics
;
 DIAMOND (Brandenburg, 2006)
 MERCURY (Bruno et al. 2002)
;
_computing_publication_material  'WINGX (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXL-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 10.4223
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'SuperNova, Dual, Cu at zero, Atlas'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_source         'SuperNova (Cu) X-ray Source'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0338
_diffrn_reflns_av_sigmaI/netI    0.0322
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            10020
_diffrn_reflns_theta_full        66.98
_diffrn_reflns_theta_max         66.98
_diffrn_reflns_theta_min         3.33
_exptl_absorpt_coefficient_mu    1.843
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.78403
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
'Empirical absorption correction (CrysAlis RED, Oxford Diffraction)'
_exptl_crystal_colour            Colorless
_exptl_crystal_density_diffrn    1.403
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             744
_exptl_crystal_size_max          0.12
_exptl_crystal_size_mid          0.03
_exptl_crystal_size_min          0.01
_refine_diff_density_max         0.280
_refine_diff_density_min         -0.306
_refine_diff_density_rms         0.049
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.048
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     235
_refine_ls_number_reflns         3022
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.048
_refine_ls_R_factor_all          0.0418
_refine_ls_R_factor_gt           0.0335
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0544P)^2^+0.1550P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0863
_refine_ls_wR_factor_ref         0.0916
_reflns_number_gt                2575
_reflns_number_total             3022
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol6b01929_si_004.cif
_cod_data_source_block           shelxl
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to
/usr/data/users/saulius/crontab/automatic-downloads/rss-feeds/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 4268 2015-11-12 08:31:59Z antanas 

 Adding full bibliography for 1543767--1543769.cif.
;
_cod_original_cell_volume        1697.26(9)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               1543767