Asymmetric Michael additions of α-cyanoacetates by soft Lewis acid/hard Brønsted acid catalysis: stereodivergency with bi- vs. monometallic catalysts
Eitel, Simon H.; Jautze, Sascha; Frey, Wolfgang; Peters, René; Chemical Science 4 (2013) 2218–; doi:10.1039/c3sc50419k

data_1514695
_publ_section_title
;
 Asymmetric Michael additions of \a-cyanoacetates by soft Lewis acid/hard
 Br\/onsted acid catalysis: stereodivergency with bi- vs. monometallic
 catalysts
;
_journal_issue                   5
_journal_name_full               'Chemical Science'
_journal_page_first              2218
_journal_paper_doi               10.1039/c3sc50419k
_journal_volume                  4
_journal_year                    2013
_chemical_formula_moiety         'C20 H27 N O4'
_chemical_formula_sum            'C20 H27 N O4'
_chemical_formula_weight         345.43
_chemical_name_systematic
;
tert-Butyl-2-cyano-2-(3-hydroxycyclohexyl)-2-(4-methoxyphenyl)acetate
;
_space_group_IT_number           33
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2n'
_symmetry_space_group_name_H-M   'P n a 21'
_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            8
_cell_length_a                   16.349(3)
_cell_length_b                   11.424(3)
_cell_length_c                   20.499(5)
_cell_measurement_reflns_used    30
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      12
_cell_measurement_theta_min      10
_cell_volume                     3828.6(15)
_computing_cell_refinement       'Siemens P3/PC Data Collection System'
_computing_data_collection       'Siemens P3/PC Data Collection System'
_computing_data_reduction        'SHELXTL-plus, XDISK (Sheldrick, 1991)'
_computing_molecular_graphics    'SHELXTL-plus, XP (Sheldrick, 1991)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Nicolet P3'
_diffrn_measurement_method       Wyckoff-Scan
_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  0.0229
_diffrn_reflns_av_sigmaI/netI    0.0913
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_number            8508
_diffrn_reflns_theta_full        26.99
_diffrn_reflns_theta_max         26.99
_diffrn_reflns_theta_min         1.99
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 50
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.083
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.199
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plates
_exptl_crystal_F_000             1488
_exptl_crystal_size_max          0.8
_exptl_crystal_size_mid          0.3
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.184
_refine_diff_density_min         -0.199
_refine_diff_density_rms         0.044
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -1.9(17)
_refine_ls_extinction_coef       0.00109(18)
_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   1.048
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     468
_refine_ls_number_reflns         8372
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.048
_refine_ls_R_factor_all          0.1600
_refine_ls_R_factor_gt           0.0787
_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^)+(0.0361P)^2^+1.2232P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1325
_refine_ls_wR_factor_ref         0.1553
_reflns_number_gt                4570
_reflns_number_total             8372
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c3sc50419k.txt
_cod_data_source_block           s1755rm1
_cod_database_code               1514695