Cyclization of <i>N</i>-Boc-(<i>E</i>)-α,β-unsaturated γ-amino acid active esters into <i>N</i>-Boc-(<i>Z</i>)-α,β-unsaturated γ-lactams through <i>E</i> → <i>Z</i> isomerization.
Singh, Manjeet; Kumar, Manish; Nalawade, Sachin A.; Puneeth Kumar, DRGKoppalu R; Gopi, Hosahudya N.; Organic & biomolecular chemistry 21 (2023) 3766–3769; doi:10.1039/d3ob00127j

data_7159289
_publ_section_title
;
 Cyclization of <i>N</i>-Boc-(<i>E</i>)-&#x3b1;,&#x3b2;-unsaturated
 &#x3b3;-amino acid active esters into
 <i>N</i>-Boc-(<i>Z</i>)-&#x3b1;,&#x3b2;-unsaturated &#x3b3;-lactams
 through <i>E</i> &#x2192; <i>Z</i> isomerization.
;
_journal_issue                   18
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              3766
_journal_page_last               3769
_journal_paper_doi               10.1039/d3ob00127j
_journal_volume                  21
_journal_year                    2023
_chemical_formula_moiety         C22
_chemical_formula_sum            'C22 H24 N2 O6'
_chemical_formula_weight         412.43
_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'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2018/3
_audit_update_record
;
2022-10-11 deposited with the CCDC.	2023-04-14 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   6.1910(7)
_cell_length_b                   14.7184(16)
_cell_length_c                   22.774(3)
_cell_measurement_reflns_used    9863
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      66.72
_cell_measurement_theta_min      3.58
_cell_volume                     2075.2(4)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2018/3 (Sheldrick, 2018)'
_computing_structure_solution    'SHELXT 2014/5 (Sheldrick, 2014)'
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.1486
_diffrn_reflns_av_unetI/netI     0.0430
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 1.000
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            69965
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        66.768
_diffrn_reflns_theta_max         66.768
_diffrn_reflns_theta_min         3.575
_exptl_absorpt_coefficient_mu    0.803
_exptl_crystal_colour            Colourless
_exptl_crystal_density_diffrn    1.320
_exptl_crystal_description       Needle
_exptl_crystal_F_000             872
_refine_diff_density_max         0.186
_refine_diff_density_min         -0.202
_refine_diff_density_rms         0.046
_refine_ls_abs_structure_details
;
 Flack x determined using 1126 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.25(12)
_refine_ls_extinction_coef       0.0029(4)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2018/3 (Sheldrick 2018)'
_refine_ls_goodness_of_fit_ref   1.037
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     275
_refine_ls_number_reflns         3681
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.037
_refine_ls_R_factor_all          0.0550
_refine_ls_R_factor_gt           0.0408
_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^)+(0.0586P)^2^+0.0524P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0922
_refine_ls_wR_factor_ref         0.0993
_reflns_Friedel_coverage         0.716
_reflns_Friedel_fraction_full    0.999
_reflns_Friedel_fraction_max     0.999
_reflns_number_gt                3070
_reflns_number_total             3681
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d3ob00127j2.cif
_cod_data_source_block           1l
_cod_depositor_comments
'Adding full bibliography for 7159285--7159290.cif.'
_cod_database_code               7159289
_shelx_shelxl_version_number     2018/3
_shelx_res_checksum              26604