A concise route to beta-Cyclopropyl amino acids utilizing 1,2-dioxines and stabilized phosphonate nucleophiles.
Avery, Thomas D.; Greatrex, Ben W.; Pedersen, Daniel Sejer; Taylor, Dennis K.; Tiekink, Edward R. T.; The Journal of organic chemistry 73 (2008) 2633–2640; doi:10.1021/jo7024256

data_4029551
_publ_section_title
;
 A concise route to beta-Cyclopropyl amino acids utilizing 1,2-dioxines
 and stabilized phosphonate nucleophiles.
;
_journal_issue                   7
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              2633
_journal_page_last               2640
_journal_paper_doi               10.1021/jo7024256
_journal_volume                  73
_journal_year                    2008
_chemical_formula_moiety         'C22 H23 N O5'
_chemical_formula_sum            'C22 H23 N O5'
_chemical_formula_weight         381.41
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 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
_cell_angle_beta                 97.521(2)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   11.8275(9)
_cell_length_b                   17.1277(14)
_cell_length_c                   9.6366(8)
_cell_measurement_reflns_used    3297
_cell_measurement_temperature    223(2)
_cell_measurement_theta_max      29.8
_cell_measurement_theta_min      2.1
_cell_volume                     1935.4(3)
_computing_cell_refinement       'SAINT (Bruker, 2000)'
_computing_data_collection       'SMART (Bruker, 2000)'
_computing_data_reduction        'SHELXTL (Bruker, 2000)'
_computing_molecular_graphics    'ORTEPII (Johnson, 1976)'
_computing_publication_material  SHELXL-97
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR92 (Altomare et al., 1993)'
_diffrn_ambient_temperature      223(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker AXS SMART CCD diffractometer'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.036
_diffrn_reflns_av_sigmaI/netI    0.039
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            13568
_diffrn_reflns_theta_full        27.5
_diffrn_reflns_theta_max         27.5
_diffrn_reflns_theta_min         1.7
_diffrn_standards_decay_%        0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.093
_exptl_absorpt_correction_T_max  1
_exptl_absorpt_correction_T_min  0.528
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'ABSCOR (Higashi, 1995)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.309
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             808
_exptl_crystal_size_max          0.31
_exptl_crystal_size_mid          0.17
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.31
_refine_diff_density_min         -0.38
_refine_diff_density_rms         0.067
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.04
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     254
_refine_ls_number_reflns         4453
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.04
_refine_ls_R_factor_all          0.071
_refine_ls_R_factor_gt           0.055
_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^)+(0.0851P)^2^+0.6266P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.141
_refine_ls_wR_factor_ref         0.156
_reflns_number_gt                3538
_reflns_number_total             4453
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            jo7024256-file002.cif
_cod_data_source_block           26a
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               4029551