Synthetic Access to All Four Stereoisomers of Oxetin.
Kassir, Ahmad F.; Ragab, Sherif S.; Nguyen, Thao A. M.; Charnay-Pouget, Florence; Guillot, Régis; Scherrmann, Marie-Christine; Boddaert, Thomas; Aitken, David J.; The Journal of organic chemistry 81 (2016) 9983–9991; doi:10.1021/acs.joc.6b01795

data_4037233
_publ_section_title
;
 Synthetic Access to All Four Stereoisomers of Oxetin.
;
_journal_issue                   20
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              9983
_journal_page_last               9991
_journal_paper_doi               10.1021/acs.joc.6b01795
_journal_volume                  81
_journal_year                    2016
_chemical_absolute_configuration syn
_chemical_formula_moiety         'C19 H24 N2 O6'
_chemical_formula_sum            'C19 H24 N2 O6'
_chemical_formula_weight         376.40
_space_group_crystal_system      orthorhombic
_space_group_IT_number           19
_space_group_name_Hall           'P 2ac 2ab'
_space_group_name_H-M_alt        'P 21 21 21'
_symmetry_cell_setting           orthorhombic
_symmetry_Int_Tables_number      19
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2013
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   7.1423(3)
_cell_length_b                   10.4505(5)
_cell_length_c                   25.2828(11)
_cell_measurement_reflns_used    9558
_cell_measurement_temperature    100(1)
_cell_measurement_theta_max      30.52
_cell_measurement_theta_min      2.53
_cell_volume                     1887.12(15)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_structure_refinement  'SHELXL-2013 (Sheldrick, 2013)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      100(1)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Bruker VENTURE PHOTON100 CMOS'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0388
_diffrn_reflns_av_unetI/netI     0.0225
_diffrn_reflns_Laue_measured_fraction_full 0.996
_diffrn_reflns_Laue_measured_fraction_max 0.997
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       36
_diffrn_reflns_limit_l_min       -36
_diffrn_reflns_number            52959
_diffrn_reflns_point_group_measured_fraction_full 0.998
_diffrn_reflns_point_group_measured_fraction_max 0.998
_diffrn_reflns_theta_full        25.000
_diffrn_reflns_theta_max         30.577
_diffrn_reflns_theta_min         2.529
_diffrn_source_type              'VENTURE PHOTON Bruker ICMMO '
_exptl_absorpt_coefficient_mu    0.099
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.325
_exptl_crystal_description       needle
_exptl_crystal_F_000             800
_exptl_crystal_size_max          0.400
_exptl_crystal_size_mid          0.140
_exptl_crystal_size_min          0.100
_refine_diff_density_max         0.259
_refine_diff_density_min         -0.269
_refine_diff_density_rms         0.049
_refine_ls_abs_structure_details
;
 Flack x determined using 2218 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons and Flack (2004), Acta Cryst. A60, s61).
;
_refine_ls_abs_structure_Flack   0.34(16)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.056
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     248
_refine_ls_number_reflns         5781
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.056
_refine_ls_R_factor_all          0.0392
_refine_ls_R_factor_gt           0.0347
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0483P)^2^+0.2658P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0811
_refine_ls_wR_factor_ref         0.0832
_reflns_Friedel_coverage         0.757
_reflns_Friedel_fraction_full    1.000
_reflns_Friedel_fraction_max     0.998
_reflns_number_gt                5371
_reflns_number_total             5781
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            jo6b01795_si_002.cif
_cod_data_source_block           12ab2
_cod_database_code               4037233
_shelx_estimated_absorpt_t_min   0.961
_shelx_estimated_absorpt_t_max   0.990
_shelxl_version_number           2013-4
_shelx_res_checksum              63724
_shelx_hkl_checksum              75833