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_7152527
_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_moiety         'C21 H21 N3 O2'
_chemical_formula_sum            'C21 H21 N3 O2'
_chemical_formula_weight         347.41
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                73.23(3)
_cell_angle_beta                 84.08(3)
_cell_angle_gamma                83.37(3)
_cell_formula_units_Z            4
_cell_length_a                   11.086(2)
_cell_length_b                   12.727(3)
_cell_length_c                   13.649(3)
_cell_measurement_reflns_used    5701
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      27.4850
_cell_measurement_theta_min      1.5625
_cell_volume                     1826.6(7)
_computing_cell_refinement       'CrystalClear (Rigaku Inc., 2008)'
_computing_data_collection       'CrystalClear (Rigaku Inc., 2008)'
_computing_data_reduction        'CrystalClear (Rigaku Inc., 2008)'
_computing_molecular_graphics
;
Mercury: visualization and analysis of crystal structures, C. F. Macrae,
P. R. Edgington, P. McCabe, E. Pidcock, G. P. Shields, R. Taylor,
M. Towler and J. van de Streek, J. Appl. Cryst., 39, 453-457, 2006.
;
_computing_publication_material  'SHELX-97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELX-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELX-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      173(2)
_diffrn_detector_area_resol_mean 28.5714
_diffrn_measured_fraction_theta_full 0.990
_diffrn_measured_fraction_theta_max 0.990
_diffrn_measurement_device_type  'Saturn724+ CCD'
_diffrn_measurement_method       '\w scans at fixed \c = 45\%'
_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  0.0389
_diffrn_reflns_av_sigmaI/netI    0.0485
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            13045
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         2.50
_exptl_absorpt_coefficient_mu    0.083
_exptl_absorpt_correction_T_max  1.0000
_exptl_absorpt_correction_T_min  0.6891
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'CrystalClear (Rigaku Inc., 2008)'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.263
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             736
_exptl_crystal_size_max          0.26
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.23
_refine_diff_density_max         0.380
_refine_diff_density_min         -0.217
_refine_diff_density_rms         0.040
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.143
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     469
_refine_ls_number_reflns         6362
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.143
_refine_ls_R_factor_all          0.0755
_refine_ls_R_factor_gt           0.0655
_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^)+(0.0361P)^2^+0.9153P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1300
_refine_ls_wR_factor_ref         0.1364
_reflns_number_gt                5553
_reflns_number_total             6362
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c2ob25799h.txt
_cod_data_source_block           a
_cod_original_cell_volume        1826.4(6)
_cod_original_sg_symbol_H-M      P-1
_cod_database_code               7152527