One-pot preparation of piperazines by regioselective ring-opening of non-activated arylaziridines.
Trinchera, Piera; Musio, Biagia; Degennaro, Leonardo; Moliterni, Anna; Falcicchio, Aurelia; Luisi, Renzo; Organic & biomolecular chemistry 10 (2012) 1962–1965; doi:10.1039/c2ob07099e

data_7152240
_publ_section_title
;
 One-pot preparation of piperazines by regioselective ring-opening of
 non-activated arylaziridines.
;
_journal_issue                   10
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              1962
_journal_page_last               1965
_journal_paper_doi               10.1039/c2ob07099e
_journal_volume                  10
_journal_year                    2012
_chemical_formula_sum            'C18 H20 Cl2 N2'
_chemical_formula_weight         335.26
_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                 90.574(18)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   9.783(3)
_cell_length_b                   13.775(3)
_cell_length_c                   12.7176(12)
_cell_measurement_reflns_used    3892
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      27.57
_cell_measurement_theta_min      5.03
_cell_volume                     1713.7(7)
_computing_cell_refinement       'DIRAX (Duisenberg,1992)'
_computing_data_collection       'COLLECT (Nonius, 2002) '
_computing_data_reduction        'EVAL (Nonius, 2002)'
_computing_publication_material  'WinGX (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution
'SIR2011, updated version of SIR2008 (Burla et al., 2007)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.980
_diffrn_measured_fraction_theta_max 0.980
_diffrn_measurement_device_type  'Bruker-Nonius KappaCCD'
_diffrn_measurement_method       '\f scans and \w scans'
_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  0.1125
_diffrn_reflns_av_sigmaI/netI    0.1349
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            18747
_diffrn_reflns_theta_full        27.57
_diffrn_reflns_theta_max         27.57
_diffrn_reflns_theta_min         5.03
_exptl_absorpt_coefficient_mu    0.377
_exptl_absorpt_correction_T_max  0.9562
_exptl_absorpt_correction_T_min  0.8794
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'SADABS (Sheldrick, 2002)'
_exptl_crystal_colour            white
_exptl_crystal_density_diffrn    1.299
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             704
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.12
_refine_diff_density_max         0.139
_refine_diff_density_min         -0.150
_refine_diff_density_rms         0.034
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.945
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     243
_refine_ls_number_reflns         3892
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.945
_refine_ls_R_factor_all          0.2083
_refine_ls_R_factor_gt           0.0594
_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^)+(0.0457P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0937
_refine_ls_wR_factor_ref         0.1287
_reflns_number_gt                1435
_reflns_number_total             3892
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c2ob07099e.txt
_cod_data_source_block           2f
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               7152240