A Simple Method of Synthesis of (±)-2,3-Diarylpiperazines and a Novel Method of Resolution of (±)-2,3-Diphenylpiperazine
Pothiappan Vairaprakash; Mariappan Periasamy; Journal of Organic Chemistry 71 (2006) 3636–3638; doi:10.1021/jo060083n

data_4021661
_publ_contact_author
;
 Prof. M. Periasamy
 School of Chemistry
 University of Hyderabad
 Hyderabad 500 046
 India
;
_publ_contact_author_email       mpsc@uohyd.ernet.in
_publ_contact_author_fax         91-40-23012460
_publ_contact_author_phone       91-40-23134814
_publ_section_title
;
 A Simple Method of Synthesis of (+-)-2,3-Diarylpiperazines
 and a Novel Method of Resolution of (+-)-2,3-Diphenylpiperazine
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              3636
_journal_page_last               3638
_journal_paper_doi               10.1021/jo060083n
_journal_volume                  71
_journal_year                    2006
_chemical_absolute_configuration rm
_chemical_formula_moiety         'C20 H28 N2 O8'
_chemical_formula_sum            'C20 H28 N2 O8'
_chemical_formula_weight         424.44
_chemical_melting_point          502.5(5)
_chemical_name_common
;
 (2S,3S)-2,3-diphenylhexahydropyrazinediium(2R,3R)-2,3-dihydroxybutanediote
;
_chemical_name_systematic
;
 (2S,3S)-2,3-diphenylhexahydropyrazinediium(2R,3R)-2,3-dihydroxybutanedioate
;
_space_group_IT_number           18
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2 2ab'
_symmetry_space_group_name_H-M   'P 21 21 2'
_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                   9.2088(10)
_cell_length_b                   35.387(4)
_cell_length_c                   6.2519(7)
_cell_measurement_reflns_used    7308
_cell_measurement_temperature    273(2)
_cell_measurement_theta_max      26.52
_cell_measurement_theta_min      2.29
_cell_volume                     2037.3(4)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SMART'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'Bruker SAINT'
_diffrn_ambient_temperature      273(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.979
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega 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  0.0451
_diffrn_reflns_av_sigmaI/netI    0.0341
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       46
_diffrn_reflns_limit_k_min       -46
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            23736
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         28.24
_diffrn_reflns_theta_min         2.29
_exptl_absorpt_coefficient_mu    0.107
_exptl_absorpt_correction_T_max  0.979
_exptl_absorpt_correction_T_min  0.955
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'multi scan'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.384
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       rectangle
_exptl_crystal_F_000             904
_exptl_crystal_preparation       water
_exptl_crystal_size_max          0.42
_exptl_crystal_size_mid          0.26
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.242
_refine_diff_density_min         -0.204
_refine_diff_density_rms         0.042
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.0(9)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.069
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     289
_refine_ls_number_reflns         4860
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.069
_refine_ls_R_factor_all          0.0562
_refine_ls_R_factor_gt           0.0483
_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^)+(0.0608P)^2^+0.0409P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1071
_refine_ls_wR_factor_ref         0.1108
_reflns_number_gt                2613
_reflns_number_total             2871
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo060083nsi20060117_095331.cif
_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.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_chemical_melting_point' value '502-503 K' was changed to '502.5(5)'
- the average value was taken and precision was estimated.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 
;
_cod_database_code               4021661