Development of oxetane modified building blocks for peptide synthesis.
Roesner, Stefan; Beadle, Jonathan D.; Tam, Leo K. B.; Wilkening, Ina; Clarkson, Guy J.; Raubo, Piotr; Shipman, Michael; Organic & biomolecular chemistry 18 (2020) 5400–5405; doi:10.1039/d0ob01208d

data_7157556
_publ_section_title
;
 Development of oxetane modified building blocks for peptide synthesis.
;
_journal_issue                   28
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              5400
_journal_page_last               5405
_journal_paper_doi               10.1039/d0ob01208d
_journal_volume                  18
_journal_year                    2020
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C27 H25 Br N2 O4, C1.75 H2'
_chemical_formula_sum            'C28.75 H27 Br N2 O4'
_chemical_formula_weight         544.43
_space_group_crystal_system      monoclinic
_space_group_IT_number           5
_space_group_name_Hall           'C 2y'
_space_group_name_H-M_alt        'C 1 2 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_audit_creation_date             2017-08-16
_audit_creation_method
;
Olex2 1.2
(compiled 2017.08.10 svn.r3461 for OlexSys, GUI svn.r5375)
;
_audit_update_record
;
2020-05-22 deposited with the CCDC.	2020-06-29 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 95.2280(10)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   25.7843(4)
_cell_length_b                   5.30700(10)
_cell_length_c                   18.5521(3)
_cell_measurement_reflns_used    9496
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      69.9180
_cell_measurement_theta_min      3.4000
_cell_volume                     2528.06(7)
_computing_cell_refinement       'CrysAlisPro 1.171.39.30d (Rigaku OD, 2017)'
_computing_data_collection       'CrysAlisPro 1.171.39.30d (Rigaku OD, 2017)'
_computing_data_reduction        'CrysAlisPro 1.171.39.30d (Rigaku OD, 2017)'
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'ShelXL (Sheldrick, 2015)'
_computing_structure_solution    'ShelXT (Sheldrick, 2015)'
_diffrn_ambient_temperature      100(2)
_diffrn_detector                 'CCD plate'
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_details
;
List of Runs (angles in degrees, time in seconds):

  # Type    Start    End  Width  t~exp~   \w     \q     \k     \f   Frames
  1  \w    -84.00  94.00   0.50    1.00    --    5.00  11.00  60.00  356
  2  \w    -84.00  94.00   0.50    1.00    --    5.00  14.00-150.00  356
  3  \w    -84.00  94.00   0.50    1.00    --    5.00  29.00-150.00  356
  4  \w     38.00  91.00   0.50    1.00    --    5.00  29.00 -30.00  106
  5  \w    -54.00 -12.00   0.50    1.00    --    5.00  29.00 -30.00   84
  6  \w    -84.00  90.00   0.50    1.00    --    5.00  43.00-150.00  348
  7  \w     47.00  94.00   0.50    1.00    --    5.00  60.00   0.00   94
  8  \w   -179.00  -1.00   0.50    4.00    --  -90.00  11.00  60.00  356
  9  \w   -111.00  -1.00   0.50    4.00    --  -90.00  29.00 -60.00  220
 10  \w   -108.00  -1.00   0.50    4.00    --  -90.00  43.00 -30.00  214
 11  \w   -175.00-147.00   0.50    4.00    --  -90.00  43.00 -60.00   56
 12  \w   -131.00 -88.00   0.50    4.00    --  -90.00  43.00 -90.00   86
 13  \w   -136.00-110.00   0.50    4.00    --  -90.00  43.00 -30.00   52
 14  \w   -150.00 -30.00   0.50    4.00    --  -90.00  43.00  30.00  240
 15  \w   -174.00  -1.00   0.50    4.00    --  -90.00  43.00   0.00  346
 16  \w    -27.00  -1.00   0.50    4.00    --  -90.00  43.00  30.00   52
 17  \w    -27.00  -2.00   0.50    4.00    --  -90.00  43.00 -60.00   50
 18  \w    -37.00  -2.00   0.50    4.00    --  -90.00  43.00 -90.00   70
 19  \w    -27.00  -1.00   0.50    4.00    --  -90.00  57.00 -60.00   52
 20  \w   -165.00-116.00   0.50    4.00    --  -90.00  57.00-180.00   98
 21  \w    -27.00  -1.00   0.50    4.00    --  -90.00  57.00 -30.00   52
 22  \w   -145.00 -83.00   0.50    4.00    --  -90.00  57.00  60.00  124
 23  \w    -27.00  -1.00   0.50    4.00    --  -90.00  57.00  30.00   52
 24  \w    -26.00  -1.00   0.50    4.00    --  -90.00  57.00 -90.00   50
 25  \w    -28.00  -2.00   0.50    4.00    --  -90.00  57.00   0.00   52
 26  \w    -26.00  -1.00   0.50    4.00    --  -90.00  57.00-120.00   50
 27  \w   -115.00 -89.00   0.50    4.00    --  -90.00  57.00-120.00   52
 28  \w   -179.00 -42.00   0.50    4.00    --  -90.00  57.00 -90.00  274
 29  \w    -31.00  -2.00   0.50    4.00    --  -90.00  57.00  60.00   58
 30  \w   -160.00-135.00   0.50    4.00    --  -90.00  60.00 -30.00   50
 31  \w    -27.00  -1.00   0.50    4.00    --  -90.00  60.00 -30.00   52
 32  \w    -38.00  -3.00   0.50    4.00    --  -90.00  60.00 -60.00   70
 33  \w    -51.00  -1.00   0.50    4.00    --  -90.00  60.00   0.00  100
 34  \w    -42.00  -2.00   0.50    4.00    --  -90.00  60.00  30.00   80
 35  \w   -178.00-115.00   0.50    4.00    --  -90.00  60.00 -90.00  126
 36  \w    -29.00  -2.00   0.50    4.00    --  -90.00  60.00 -90.00   54
 37  \w   -154.00-128.00   0.50    4.00    --  -90.00  60.00  30.00   52
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'XtaLAB AFC11 (RCD3): quarter-chi single'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_type
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      -0.0380748000
_diffrn_orient_matrix_UB_12      -0.0459262000
_diffrn_orient_matrix_UB_13      0.0580023000
_diffrn_orient_matrix_UB_21      0.0452528000
_diffrn_orient_matrix_UB_22      0.0260128000
_diffrn_orient_matrix_UB_23      0.0597512000
_diffrn_orient_matrix_UB_31      -0.0102206000
_diffrn_orient_matrix_UB_32      0.2854395000
_diffrn_orient_matrix_UB_33      0.0038747000
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0686
_diffrn_reflns_av_unetI/netI     0.0454
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 1.000
_diffrn_reflns_limit_h_max       30
_diffrn_reflns_limit_h_min       -30
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            22540
_diffrn_reflns_point_group_measured_fraction_full 0.960
_diffrn_reflns_point_group_measured_fraction_max 0.960
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         68.160
_diffrn_reflns_theta_min         3.442
_diffrn_source                   'fine-focus sealed X-ray tube'
_diffrn_source_type              'Enhance (Cu) X-ray Source'
_exptl_absorpt_coefficient_mu    2.526
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.59789
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
'CrysAlisPro 1.171.39.30d (Rigaku Oxford Diffraction, 2017) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.'
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.430
_exptl_crystal_description       needle
_exptl_crystal_F_000             1122
_exptl_crystal_size_max          0.37
_exptl_crystal_size_mid          0.02
_exptl_crystal_size_min          0.02
_refine_diff_density_max         1.548
_refine_diff_density_min         -0.555
_refine_diff_density_rms         0.139
_refine_ls_abs_structure_details
;
 Flack x determined using 1518 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
Flack x: -0.02(2)  (Olex2)
Hooft y: 0.009(10) (Shelx 2016)
;
_refine_ls_abs_structure_Flack   -0.02(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.054
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     322
_refine_ls_number_reflns         4460
_refine_ls_number_restraints     2
_refine_ls_restrained_S_all      1.054
_refine_ls_R_factor_all          0.0775
_refine_ls_R_factor_gt           0.0722
_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^)+(0.1462P)^2^+4.0303P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1947
_refine_ls_wR_factor_ref         0.2005
_reflns_Friedel_coverage         0.720
_reflns_Friedel_fraction_full    0.910
_reflns_Friedel_fraction_max     0.910
_reflns_number_gt                4028
_reflns_number_total             4460
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d0ob01208d2.cif
_cod_data_source_block           jb3
_cod_depositor_comments          'Adding full bibliography for 7157556.cif.'
_cod_database_code               7157556
_shelx_shelxl_version_number     2016/6
_chemical_oxdiff_formula         'C27 H25 N2 O4 Br '
_chemical_oxdiff_usercomment     jb3(jdb07-60-01)
_shelx_estimated_absorpt_t_max   0.951
_shelx_estimated_absorpt_t_min   0.455
_reflns_odcompleteness_completeness 99.96
_reflns_odcompleteness_iscentric 1
_reflns_odcompleteness_theta     68.13
_olex2_refinement_description
;
The NHs were placed at calculated positions.
The toluene molecule was modeled at half occupancy and lies disordered on the two fold axis. 
The toluene forms and infinite column of solvent where the partially occupied toluenes were modeled 
all facing the same way and with the two fold axis passing through the methyl C1A and ring carbons C2A and C5A. 
Some DFIX restraints were used to give the disordered solvent reasonable ring bond lengths.

1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups, All N(H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2. Restrained distances
 C4A-C3A
 1.39 with sigma of 0.02
3. Others
 Fixed Sof: C1A(0.25) H1AA(0.25) H1AC(0.25) H1AB(0.25) C2A(0.25) C3A(0.5)
 H3A(0.5) C4A(0.5) H4A(0.5) C5A(0.25) H5A(0.25)
4.a Ternary CH refined with riding coordinates:
 C13(H13), C18(H18)
4.b Secondary CH2 refined with riding coordinates:
 C14(H14A,H14B), C20(H20A,H20B), C22(H22A,H22B)
4.c Me refined with riding coordinates:
 C1A(H1AA,H1AC,H1AB)
4.d Aromatic/amide H refined with riding coordinates:
 C2(H2), C3(H3), C4(H4), C5(H5), C8(H8), C9(H9), C10(H10), C11(H11), N17(H17),
 N23(H23), C26(H26), C27(H27), C29(H29), C30(H30), C3A(H3A), C4A(H4A), C5A(H5A)
4.e Idealised Me refined as rotating group:
 C18A(H18A,H18B,H18C)
;
_shelx_res_checksum              73910
_olex2_submission_special_instructions 'No special instructions were received'
_oxdiff_exptl_absorpt_empirical_details
'Empirical correction (ABSPACK) includes: - Absorption correction using spherical harmonics - Frame scaling'
_oxdiff_exptl_absorpt_empirical_full_max 1.489
_oxdiff_exptl_absorpt_empirical_full_min 0.733