Structures and Reactivities of 2-Trityl- and 2-(Triphenylsilyl)pyrrolidine-Derived Enamines: Evidence for Negative Hyperconjugation with the Trityl Group.
Erdmann, Hannes; An, Feng; Mayer, Peter; Ofial, Armin R.; Lakhdar, Sami; Mayr, Herbert; Journal of the American Chemical Society 136 (2014) 14263–; doi:10.1021/ja508065e

data_4122670
_publ_section_title
;
 Structures and Reactivities of 2-Trityl- and
 2-(Triphenylsilyl)pyrrolidine-Derived Enamines: Evidence for Negative
 Hyperconjugation with the Trityl Group.
;
_journal_issue                   40
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              14263
_journal_paper_doi               10.1021/ja508065e
_journal_volume                  136
_journal_year                    2014
_chemical_formula_moiety         'C27 H30 N O2, B F4'
_chemical_formula_sum            'C27 H30 B F4 N O2'
_chemical_formula_weight         487.337
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      14
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_block_code                C27H30NO2_BF4_rv369_mayr
_audit_creation_method           'form98_non/compatible with shelxl97-2'
_audit_update_record             07-Oct-13
_cell_angle_alpha                90.00
_cell_angle_beta                 100.629(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   9.1164(6)
_cell_length_b                   27.1275(16)
_cell_length_c                   9.9782(6)
_cell_measurement_reflns_used    116
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      27.8579
_cell_measurement_theta_min      3.1948
_cell_volume                     2425.3(3)
_computing_cell_refinement       'APEX2 v2012.4-3 (Bruker AXS)'
_computing_data_collection       'Bruker Instrument Service v3.0.21'
_computing_data_reduction        'SAINT V8.18C (Bruker AXS Inc., 2011)'
_computing_structure_refinement
;
Sheldrick, G. M. (2008).
<i>Acta Cryst.</i> A<b>64</b>, 112--122.
;
_computing_structure_solution
;
A. Altomare, M. C. Burla, M. Camalli, G. L. Cascarano, C. Giacovazzo, A.
Guagliardi, A. G. G. Moliterni, G. Polidori, R. Spagna: SIR97: a new tool for
crystal structure determination and refinement; J. Appl. Crystallogr. 1999,
32, 115-119.
;
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 10.4167
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device       'fixed-chi three-circle diffractometer'
_diffrn_measurement_device_type  'Bruker D8Venture'
_diffrn_measurement_method       'mix of phi and omega scans'
_diffrn_radiation_collimation    0.8_mm
_diffrn_radiation_monochromator  'focusing mirrors'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0521
_diffrn_reflns_av_sigmaI/netI    0.0247
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       33
_diffrn_reflns_limit_k_min       -33
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            48873
_diffrn_reflns_theta_full        26.41
_diffrn_reflns_theta_max         26.41
_diffrn_reflns_theta_min         3.00
_diffrn_source_current           50
_diffrn_source_power             2.5
_diffrn_source_type              'Bruker TXS'
_diffrn_source_voltage           50
_exptl_absorpt_coefficient_mu    0.103
_exptl_absorpt_correction_T_max  0.9585
_exptl_absorpt_correction_T_min  0.9307
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS V2012/1 (Bruker AXS Inc.)'
_exptl_crystal_colour            pink
_exptl_crystal_density_diffrn    1.33469(17)
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1024
_exptl_crystal_size_max          0.127
_exptl_crystal_size_mid          0.069
_exptl_crystal_size_min          0.069
_refine_diff_density_max         0.554
_refine_diff_density_min         -0.422
_refine_diff_density_rms         0.047
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.056
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     318
_refine_ls_number_reflns         4959
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.056
_refine_ls_R_factor_all          0.0603
_refine_ls_R_factor_gt           0.0452
_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^)+(0.0421P)^2^+1.9191P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1041
_refine_ls_wR_factor_ref         0.1123
_reflns_number_gt                4014
_reflns_number_total             4959
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja508065e_si_003.cif
_cod_data_source_block           rv369
_cod_depositor_comments
'Adding full bibliography for 4122666--4122670.cif.'
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               4122670