Synthesis of 3,4-Disubstituted Piperidines by Carbonyl Ene and Prins Cyclizations: A Switch in Diastereoselectivity between Lewis and Brønsted Acid Catalysts
Williams, Jodi T.; Bahia, Perdip Singh; Snaith, John S.; Organic Letters 4 (2002) 3727–; doi:10.1021/ol0266929

data_1507478
_publ_section_title
;
 Synthesis of 3,4-Disubstituted Piperidines by Carbonyl Ene and Prins
 Cyclizations:&#x2009; A Switch in Diastereoselectivity between Lewis and
 Br\/onsted Acid Catalysts
;
_journal_issue                   21
_journal_name_full               'Organic Letters'
_journal_page_first              3727
_journal_paper_doi               10.1021/ol0266929
_journal_volume                  4
_journal_year                    2002
_chemical_formula_sum            'C15 H21 N O3 S'
_chemical_formula_weight         295.39
_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
_cell_angle_alpha                90.00
_cell_angle_beta                 99.50(5)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.314(9)
_cell_length_b                   5.395(4)
_cell_length_c                   23.491(9)
_cell_measurement_reflns_used    2379
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      25.35
_cell_measurement_theta_min      1.68
_cell_volume                     1539.2(17)
_computing_structure_refinement  'SHELXL-93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS-86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      296(2)
_diffrn_measurement_device       'R-axis II'
_diffrn_measurement_method       'Image plate scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Rotating anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.0661
_diffrn_reflns_av_sigmaI/netI    0.0992
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -25
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_diffrn_reflns_theta_max         25.35
_diffrn_reflns_theta_min         1.68
_exptl_absorpt_coefficient_mu    0.217
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            white
_exptl_crystal_density_diffrn    1.275
_exptl_crystal_description       needle
_exptl_crystal_F_000             632
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.15
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.295
_refine_diff_density_min         -0.316
_refine_diff_density_rms         0.062
_refine_ls_extinction_coef       0.0235(76)
_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_all   1.006
_refine_ls_goodness_of_fit_obs   1.062
_refine_ls_matrix_type           full
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_refine_ls_number_reflns         2376
_refine_ls_number_restraints     0
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_refine_ls_restrained_S_obs      1.062
_refine_ls_R_factor_all          0.0922
_refine_ls_R_factor_obs          0.0666
_refine_ls_shift/esd_max         0.242
_refine_ls_shift/esd_mean        0.010
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.1008P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.2162
_refine_ls_wR_factor_obs         0.1722
_reflns_number_observed          1742
_reflns_number_total             2379
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            ol0266929_s2.cif
_cod_data_source_block           js1
_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_values 1715 2011-07-08 13:25:40Z adriana 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.1008P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to
'w=1/[\s^2^(Fo^2^)+(0.1008P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_cell_volume        1539.1(17)
_cod_original_sg_symbol_H-M      P21/c
_cod_database_code               1507478