Synthesis of 2,4-Disubstituted Piperidines via Radical Cyclization: Unexpected Enhancement in Diastereoselectivity with Tris(trimethylsilyl)silane
Lucile A. Gandon; Alexander G. Russell; Tatyana Güveli; Angela E. Brodwolf; Benson M. Kariuki; Neil Spencer; John S. Snaith; Journal of Organic Chemistry 71 (2006) 5198–5207; doi:10.1021/jo060495w

data_4021782
_publ_contact_author
;
J.S. Snaith,
School of Chemistry,
University of Birmingham,
Edgbaston, Birmingham, B15 2TT, UK
;
_publ_contact_author_email       j.s.snaith@bham.ac.uk
_publ_section_title
;
 Synthesis of 2,4-Disubstituted Piperidines via Radical Cyclization:
 Unexpected Enhancement in Diastereoselectivity with
 Tris(trimethylsilyl)silane
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              5198
_journal_page_last               5207
_journal_paper_doi               10.1021/jo060495w
_journal_volume                  71
_journal_year                    2006
_chemical_formula_sum            'C44 H55 N3 O10 S'
_chemical_formula_weight         817.97
_chemical_name_systematic
;
 ?
;
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 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                 94.791(5)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   8.2329(11)
_cell_length_b                   12.4797(16)
_cell_length_c                   20.963(3)
_cell_measurement_temperature    298(2)
_cell_volume                     2146.3(5)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 0.982
_diffrn_measured_fraction_theta_max 0.982
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0386
_diffrn_reflns_av_sigmaI/netI    0.0684
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            5414
_diffrn_reflns_theta_full        41.72
_diffrn_reflns_theta_max         41.72
_diffrn_reflns_theta_min         2.11
_exptl_absorpt_coefficient_mu    1.167
_exptl_absorpt_correction_T_max  0.9770
_exptl_absorpt_correction_T_min  0.5931
_exptl_crystal_density_diffrn    1.266
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             872
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.14
_exptl_crystal_size_min          0.02
_refine_diff_density_max         0.594
_refine_diff_density_min         -0.258
_refine_diff_density_rms         0.075
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.06(9)
_refine_ls_extinction_coef       0.0078(16)
_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   1.272
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     243
_refine_ls_number_reflns         2703
_refine_ls_number_restraints     37
_refine_ls_restrained_S_all      1.282
_refine_ls_R_factor_all          0.1308
_refine_ls_R_factor_gt           0.1045
_refine_ls_shift/su_max          0.036
_refine_ls_shift/su_mean         0.005
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.2000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2861
_refine_ls_wR_factor_ref         0.3196
_reflns_number_gt                2057
_reflns_number_total             2703
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo060495wsi20060307_104035.cif
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
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 
;
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               4021782