Asymmetric Synthesis of α,α-Disubstituted Amino Acids by Cycloaddition of (E)-Ketonitrones with Vinyl Ethers.
Zhang, Xiaofei; Cividino, Pascale; Poisson, Jean-François; Shpak-Kraievskyi, Pavlo; Laurent, Mathieu Y; Martel, Arnaud; Dujardin, Gilles; Py, Sandrine; Organic letters 16 (2014) 1936–1939; doi:10.1021/ol500483t

data_1514214
_publ_section_title
;
 Asymmetric Synthesis of \a,\a-Disubstituted Amino Acids by Cycloaddition
 of (E)-Ketonitrones with Vinyl Ethers.
;
_journal_issue                   7
_journal_name_full               'Organic letters'
_journal_page_first              1936
_journal_page_last               1939
_journal_paper_doi               10.1021/ol500483t
_journal_volume                  16
_journal_year                    2014
_chemical_absolute_configuration rm
_chemical_formula_moiety         'C14 H20 F3 N O7'
_chemical_formula_sum            'C14 H20 F3 N O7'
_chemical_formula_weight         371.31
_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                 98.572(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   9.2339(8)
_cell_length_b                   11.8223(11)
_cell_length_c                   17.1508(15)
_cell_measurement_reflns_used    1462
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      39.36
_cell_measurement_theta_min      4.159
_cell_volume                     1851.4(3)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      150(2)
_diffrn_detector_area_resol_mean 10.0
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Bruker APEXII'
_diffrn_measurement_method       '\w scans'
_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  0.1158
_diffrn_reflns_av_sigmaI/netI    0.1606
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            46140
_diffrn_reflns_theta_full        30.55
_diffrn_reflns_theta_max         30.55
_diffrn_reflns_theta_min         2.10
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.124
_exptl_absorpt_correction_T_max  0.995
_exptl_absorpt_correction_T_min  0.989
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SHELX76; Sheldrick, 2008)'
_exptl_crystal_colour            white
_exptl_crystal_density_diffrn    1.332
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       platelets
_exptl_crystal_F_000             776
_exptl_crystal_size_max          0.158
_exptl_crystal_size_mid          0.077
_exptl_crystal_size_min          0.042
_refine_diff_density_max         0.215
_refine_diff_density_min         -0.279
_refine_diff_density_rms         0.054
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.3(8)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.934
_refine_ls_hydrogen_treatment    refU
_refine_ls_matrix_type           full
_refine_ls_number_parameters     462
_refine_ls_number_reflns         11293
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.934
_refine_ls_R_factor_all          0.1921
_refine_ls_R_factor_gt           0.0601
_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^)+(0.0437P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0964
_refine_ls_wR_factor_ref         0.1313
_reflns_number_gt                4714
_reflns_number_total             11293
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol500483t_si_002.cif
_cod_data_source_block           xyc18fracafroid_0m
_cod_depositor_comments
;Adding full bibliography for
 ./tmp-cod-update-bibliographies-8800/cifs/1514214.cif.

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               1514214