Metal-free synthesis of cyclic di-oxoguanidines via one-pot sequential transformation of amines, carbodiimides and acyl dichlorides.
Zhao, Fei; Wang, Yang; Zhang, Wen-Xiong; Xi, Zhenfeng; Organic & biomolecular chemistry 10 (2012) 6266–6270; doi:10.1039/c2ob25799h

data_7152528
_publ_section_title
;
 Metal-free synthesis of cyclic di-oxoguanidines via one-pot sequential
 transformation of amines, carbodiimides and acyl dichlorides.
;
_journal_issue                   31
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              6266
_journal_page_last               6270
_journal_paper_doi               10.1039/c2ob25799h
_journal_volume                  10
_journal_year                    2012
_chemical_formula_sum            'C15 H18 Br N3 O2'
_chemical_formula_weight         352.23
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.8707(18)
_cell_length_b                   10.082(2)
_cell_length_c                   18.499(4)
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      27.48
_cell_measurement_theta_min      2.02
_cell_volume                     1654.4(6)
_computing_cell_refinement       Rapid-AUTO
_computing_data_collection       'Rapid-AUTO (Rigaku,2000)'
_computing_data_reduction        'CrystalStructure (Rigaku/MSC,2000)'
_computing_molecular_graphics    'Siemens SHELXTL V4.2,(Sheldrick,1990)'
_computing_publication_material  SHELXL-97,(Sheldrick,1997)
_computing_structure_refinement  SHELXL-97,(Sheldrick,1997)
_computing_structure_solution    SHELXS-97,(Sheldrick,1997)
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean 10.00
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Rigaku RAXIS RAPID IP'
_diffrn_measurement_method       \W
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0000
_diffrn_reflns_av_sigmaI/netI    0.1443
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            2200
_diffrn_reflns_theta_full        27.48
_diffrn_reflns_theta_max         27.48
_diffrn_reflns_theta_min         2.02
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    2.492
_exptl_absorpt_correction_T_max  0.6356
_exptl_absorpt_correction_T_min  0.5218
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details
;
HIGASHI, T. (1995). Abscor-Empirical
Absorption Correction based on Fourier
Series Approximation.
Rigaku Corporation,Tokyo,Japan.
;
_exptl_crystal_density_diffrn    1.414
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             720
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.279
_refine_diff_density_min         -0.396
_refine_diff_density_rms         0.061
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.50(3)
_refine_ls_extinction_coef       0.0128(6)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   0.735
_refine_ls_hydrogen_treatment    none
_refine_ls_matrix_type           full
_refine_ls_number_parameters     195
_refine_ls_number_reflns         2177
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.735
_refine_ls_R_factor_all          0.1173
_refine_ls_R_factor_gt           0.0398
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0521
_refine_ls_wR_factor_ref         0.0610
_reflns_number_gt                883
_reflns_number_total             2177
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c2ob25799h.txt
_cod_data_source_block           4c
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from
2010-06-29.

'_exptl_absorpt_correction_type' value 'Empirical'
changed to 'empirical' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1891 2012-01-12 08:04:46Z andrius 
;
_cod_original_cell_volume        1654.3(6)
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               7152528