3-4'-Bipiperidines via sequential [4 + 4]-[3,3]-retro-Mannich reactions.
Chen, Peiling; Carroll, Patrick J.; Sieburth, Scott McN; Organic letters 11 (2009) 4540–4543; doi:10.1021/ol901743p

data_1504151
_publ_section_title
;
 3-4'-Bipiperidines via sequential [4 + 4]-[3,3]-retro-Mannich reactions.
;
_journal_issue                   20
_journal_name_full               'Organic letters'
_journal_page_first              4540
_journal_page_last               4543
_journal_paper_doi               10.1021/ol901743p
_journal_volume                  11
_journal_year                    2009
_chemical_formula_sum            'C21 H31 N2 O4'
_chemical_formula_weight         375.48
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_Int_Tables_number      2
_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
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.009(11)
_cell_angle_beta                 106.126(7)
_cell_angle_gamma                98.122(9)
_cell_formula_units_Z            2
_cell_length_a                   8.8340(10)
_cell_length_b                   10.2781(15)
_cell_length_c                   13.2981(19)
_cell_measurement_temperature    143(1)
_cell_volume                     1147.3(3)
_computing_data_collection       'CrystalClear (Rigaku, 1999)'
_computing_data_reduction        'CrystalClear (Rigaku, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR97 (Altomare, 1999)'
_diffrn_ambient_temperature      143(1)
_diffrn_measured_fraction_theta_full 0.971
_diffrn_measured_fraction_theta_max 0.971
_diffrn_measurement_device       'CCD Area Detector'
_diffrn_measurement_device_type  'Rigaku Mercury'
_diffrn_measurement_method       'phi and omega rotations'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'rotating anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.0288
_diffrn_reflns_av_sigmaI/netI    0.0788
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            7382
_diffrn_reflns_theta_full        24.13
_diffrn_reflns_theta_max         24.13
_diffrn_reflns_theta_min         2.50
_exptl_absorpt_coefficient_mu    0.075
_exptl_absorpt_correction_T_max  1.0000
_exptl_absorpt_correction_T_min  0.7859
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_density_diffrn    1.087
_exptl_crystal_F_000             406
_exptl_crystal_size_max          0.38
_exptl_crystal_size_mid          0.18
_exptl_crystal_size_min          0.005
_refine_diff_density_max         0.190
_refine_diff_density_min         -0.262
_refine_diff_density_rms         0.052
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.984
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     269
_refine_ls_number_reflns         3553
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.984
_refine_ls_R_factor_all          0.0886
_refine_ls_R_factor_gt           0.0459
_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^)+(0.0518P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0999
_refine_ls_wR_factor_ref         0.1240
_reflns_number_gt                1925
_reflns_number_total             3553
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol901743p_si_002.cif
_cod_data_source_block           shelxl
_cod_original_sg_symbol_H-M      'P -1       '
_cod_database_code               1504151