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_1514212
_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 syn
_chemical_formula_moiety         'C18 H25 N O6'
_chemical_formula_sum            'C18 H25 N O6'
_chemical_formula_weight         351.39
_space_group_crystal_system      triclinic
_space_group_IT_number           1
_space_group_name_Hall           'P 1'
_space_group_name_H-M_alt        'P 1'
_symmetry_space_group_name_Hall  'P 1'
_symmetry_space_group_name_H-M   'P 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_date             2013-02-20
_audit_creation_method
;
  Olex2 1.1
  (compiled Sep 28 2011 20:36:17, GUI svn.r3906)
;
_cell_angle_alpha                90.89(3)
_cell_angle_beta                 94.28(3)
_cell_angle_gamma                112.44(3)
_cell_formula_units_Z            1
_cell_length_a                   6.5131(13)
_cell_length_b                   7.9315(16)
_cell_length_c                   9.954(2)
_cell_measurement_reflns_used    24
_cell_measurement_temperature    297
_cell_measurement_theta_max      22.546
_cell_measurement_theta_min      19.175
_cell_volume                     473.4(2)
_computing_cell_refinement       'CAD4 Express (Enraf Nonius, 1994)'
_computing_data_collection       'CAD4 Express (Enraf Nonius, 1994)'
_computing_data_reduction        'XCAD4 (Harms & Wocadlo, 1995)'
_computing_molecular_graphics
;
O. V. Dolomanov, L. J. Bourhis, R. J. Gildea, J. A. K. Howard and H. Puschmann,
OLEX2: a complete structure solution, refinement and analysis program.
J. Appl. Cryst. (2009). 42, 339-341.
;
_computing_publication_material
;
O. V. Dolomanov, L. J. Bourhis, R. J. Gildea, J. A. K. Howard and H. Puschmann,
OLEX2: a complete structure solution, refinement and analysis program.
J. Appl. Cryst. (2009). 42, 339-341.
;
_computing_structure_refinement
;
SHELXL, G.M. Sheldrick, Acta Cryst.
(2008). A64, 112-122
;
_computing_structure_solution
;
SHELXS, G.M. Sheldrick, Acta Cryst.
(2008). A64, 112-122
;
_diffrn_ambient_temperature      297
_diffrn_detector                 'scintillation LiI'
_diffrn_detector_dtime           1.195
_diffrn_detector_type            'scintillation LiI'
_diffrn_measured_fraction_theta_full 0.974
_diffrn_measured_fraction_theta_max 0.974
_diffrn_measurement_device       '\k-geometry diffractometer'
_diffrn_measurement_device_type  'Bruker-Enraf-Nonius MACH3'
_diffrn_measurement_method       'non-profiled \w/2\t scans'
_diffrn_orient_matrix_type
;
  x-axis points to radiation source
  the matrix is specified in reciprocal space
;
_diffrn_orient_matrix_UB_11      -0.052753
_diffrn_orient_matrix_UB_12      -0.051233
_diffrn_orient_matrix_UB_13      -0.131058
_diffrn_orient_matrix_UB_21      -0.063419
_diffrn_orient_matrix_UB_22      -0.065925
_diffrn_orient_matrix_UB_23      0.038214
_diffrn_orient_matrix_UB_31      -0.058504
_diffrn_orient_matrix_UB_32      0.042313
_diffrn_orient_matrix_UB_33      -0.003596
_diffrn_radiation_detector       'scintillation counter'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0000
_diffrn_reflns_av_unetI/netI     0.0196
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            1972
_diffrn_reflns_theta_full        72.96
_diffrn_reflns_theta_max         72.96
_diffrn_reflns_theta_min         4.46
_diffrn_source                   'Enraf Nonius FR590'
_diffrn_source_target            Cu
_diffrn_source_type              'fine-focus sealed tube'
_diffrn_standards_decay_%        2
_diffrn_standards_interval_time  120
_diffrn_standards_number         2
_exptl_absorpt_coefficient_mu    0.767
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.233
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             188
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.4
_exptl_crystal_size_min          0.39
_refine_diff_density_max         0.276
_refine_diff_density_min         -0.279
_refine_diff_density_rms         0.051
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.1(4)
_refine_ls_extinction_coef       0.219(15)
_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   1.045
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     225
_refine_ls_number_reflns         1972
_refine_ls_number_restraints     3
_refine_ls_restrained_S_all      1.044
_refine_ls_R_factor_all          0.0679
_refine_ls_R_factor_gt           0.0526
_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^)+(0.1049P)^2^+0.0599P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1394
_refine_ls_wR_factor_ref         0.1529
_reflns_number_gt                1672
_reflns_number_total             1972
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol500483t_si_002.cif
_cod_data_source_block           transf
_cod_depositor_comments
;Adding full bibliography for
 ./tmp-cod-update-bibliographies-8800/cifs/1514212.cif.
;
_cod_original_cell_volume        473.41(16)
_cod_database_code               1514212
_diffrn_standards_decay_corr_max 1.004
_diffrn_standards_decay_corr_min 0.904