Asymmetric Synthesis of α-Methyl-α-Amino Acids via Diastereoselective Alkylation of (1S)-(+)-3-Carene Derived Tricyclic Iminolactone
Ta-Jung Lu; Cheng-Kun Lin; Journal of Organic Chemistry 76 (2011) 1621–1633; doi:10.1021/jo1022537

data_4026101
_publ_section_title
;
 Asymmetric Synthesis of \a-Methyl-\a-Amino Acids via Diastereoselective
 Alkylation of (1S)-(+)-3-Carene Derived Tricyclic Iminolactone
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              1621
_journal_page_last               1633
_journal_paper_doi               10.1021/jo1022537
_journal_volume                  76
_journal_year                    2011
_chemical_absolute_configuration unk
_chemical_formula_moiety         'C20 H25 N O2'
_chemical_formula_sum            'C20 H25 N O2'
_chemical_formula_weight         311.41
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_Int_Tables_number      19
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 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            4
_cell_length_a                   9.7844(2)
_cell_length_b                   10.1122(3)
_cell_length_c                   17.8873(4)
_cell_measurement_reflns_used    4877
_cell_measurement_temperature    297(2)
_cell_measurement_theta_max      71.6130
_cell_measurement_theta_min      4.3630
_cell_volume                     1769.80(8)
_computing_cell_refinement
; 
CrysAlis RED, Oxford Diffraction Ltd., 
Version 1.171.32.29 (release 10-06-2008 CrysAlis171 .NET) 
(compiled Jun 10 2008,16:49:55) 
;
_computing_data_collection
; 
CrysAlis CCD, Oxford Diffraction Ltd., 
Version 1.171.32.29 (release 10-06-2008 CrysAlis171 .NET) 
(compiled Jun 10 2008,16:49:55) 
;
_computing_data_reduction
; 
CrysAlis RED, Oxford Diffraction Ltd., 
Version 1.171.32.29 (release 10-06-2008 CrysAlis171 .NET) 
(compiled Jun 10 2008,16:49:55) 
;
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      297(2)
_diffrn_measured_fraction_theta_full 0.991
_diffrn_measured_fraction_theta_max 0.984
_diffrn_measurement_device_type  'CCD detector'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0149
_diffrn_reflns_av_sigmaI/netI    0.0204
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            7562
_diffrn_reflns_theta_full        71.00
_diffrn_reflns_theta_max         71.68
_diffrn_reflns_theta_min         4.94
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    0.587
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.79964
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
; 
CrysAlisPro, Oxford Diffraction Ltd., 
Version 1.171.33.46 (release 27-08-2009 CrysAlis171 .NET) 
(compiled Aug 27 2009,17:19:36) 
empirical absorption correction using spherical harmonics, 
 implemented in SCALE3 ABSPACK scaling algorithm. 
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.169
_exptl_crystal_description       parallelepiped
_exptl_crystal_F_000             672
_exptl_crystal_size_max          0.62
_exptl_crystal_size_mid          0.58
_exptl_crystal_size_min          0.48
_refine_diff_density_max         0.131
_refine_diff_density_min         -0.114
_refine_diff_density_rms         0.024
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.0(3)
_refine_ls_extinction_coef       0.0106(10)
_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   1.128
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     209
_refine_ls_number_reflns         3366
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.128
_refine_ls_R_factor_all          0.0437
_refine_ls_R_factor_gt           0.0375
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0632P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1063
_refine_ls_wR_factor_ref         0.1089
_reflns_number_gt                2863
_reflns_number_total             3366
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo1022537_si_002.cif
_cod_data_source_block           mebn
_cod_database_code               4026101