An efficient synthesis strategy to the core structure of 6-5-6-5-6-membered epipolythiodiketopiperazines.
Zipfel, Hannes F.; Carreira, Erick M.; Organic letters 16 (2014) 2854–2857; doi:10.1021/ol500990f

data_1516147
_publ_section_title
;
 An efficient synthesis strategy to the core structure of
 6-5-6-5-6-membered epipolythiodiketopiperazines.
;
_journal_issue                   11
_journal_name_full               'Organic letters'
_journal_page_first              2854
_journal_page_last               2857
_journal_paper_doi               10.1021/ol500990f
_journal_volume                  16
_journal_year                    2014
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C7 H9 Br O2'
_chemical_formula_sum            'C7 H9 Br O2'
_chemical_formula_weight         205.05
_chemical_name_systematic
((1S,2R,4S)-2-bromo-7-oxabicyclo[2.2.1]hept-5-en-2-yl)methanol
_space_group_crystal_system      trigonal
_space_group_IT_number           145
_space_group_name_Hall           'P 32'
_space_group_name_H-M_alt        'P 32'
_symmetry_cell_setting           trigonal
_symmetry_Int_Tables_number      145
_symmetry_space_group_name_Hall  'P 32'
_symmetry_space_group_name_H-M   'P 32'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_audit_creation_date             2013-11-11
_audit_creation_method
;
Olex2 1.2
(compiled 2013.09.17 svn.r2790 for OlexSys, GUI svn.r4601)
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                120
_cell_formula_units_Z            9
_cell_length_a                   17.8119(15)
_cell_length_b                   17.8119(15)
_cell_length_c                   6.2589(5)
_cell_measurement_reflns_used    7903
_cell_measurement_temperature    99.99
_cell_measurement_theta_max      30.058
_cell_measurement_theta_min      3.49
_cell_volume                     1719.7(2)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'SAINT v8.27A (Bruker, 2012)'
_computing_molecular_graphics    OLEX2
_computing_publication_material  OLEX2
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100.0(2)
_diffrn_detector                 'Bruker APEX2 area detector'
_diffrn_detector_area_resol_mean 8.33
_diffrn_detector_type            'CCD area detector'
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device       'kappa-stage diffractometer'
_diffrn_measurement_device_type  'Bruker Kappa Apex2 Duo'
_diffrn_measurement_method       '\w and \f scans'
_diffrn_radiation_monochromator  'focusing graphite'
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_radiation_xray_symbol    K-L~3~
_diffrn_reflns_av_R_equivalents  0.0301
_diffrn_reflns_av_unetI/netI     0.0425
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 1.000
_diffrn_reflns_limit_h_max       25
_diffrn_reflns_limit_h_min       -25
_diffrn_reflns_limit_k_max       25
_diffrn_reflns_limit_k_min       -25
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            18642
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         30.513
_diffrn_reflns_theta_min         1.320
_diffrn_source                   'sealed tube'
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    5.313
_exptl_absorpt_correction_T_max  0.8134
_exptl_absorpt_correction_T_min  0.6022
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2012/1 (Bruker,2012) was used for absorption correction.
wR2(int) was 0.0805 before and 0.0528 after correction.
The Ratio of minimum to maximum transmission is 0.7403.
The \l/2 correction factor is 0.0015.
;
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.782
_exptl_crystal_description       needle
_exptl_crystal_F_000             918
_exptl_crystal_recrystallization_method
'crystallized from a diethyether/pentane mixture'
_exptl_crystal_size_max          0.32
_exptl_crystal_size_mid          0.08
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.742
_refine_diff_density_min         -0.476
_refine_diff_density_rms         0.070
_refine_ls_abs_structure_details
;
 Flack x determined using 2628 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons and Flack (2004), Acta Cryst. A60, s61).
;
_refine_ls_abs_structure_Flack   0.008(5)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.033
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     275
_refine_ls_number_reflns         6360
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.033
_refine_ls_R_factor_all          0.0255
_refine_ls_R_factor_gt           0.0235
_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^)+(0.0129P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0456
_refine_ls_wR_factor_ref         0.0467
_reflns_Friedel_coverage         0.998
_reflns_Friedel_fraction_full    1.000
_reflns_Friedel_fraction_max     0.998
_reflns_number_gt                6143
_reflns_number_total             6360
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ol500990f_si_002.cif
_cod_data_source_block           mo_ca041113_0m
_cod_depositor_comments
'Adding full bibliography for 1516147--1516149.cif.'
_cod_original_cell_volume        1719.7(3)
_cod_database_code               1516147
_shelxl_version_number           2013-4
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups
 At 1.5 times of:
  All O(H) groups
2.a Ternary CH refined with riding coordinates:
 C2(H2A), C5(H5), C2A(H2AB), C5A(H5A), C2B(H2BA), C5B(H5B)
2.b Secondary CH2 refined with riding coordinates:
 C6(H6A,H6B), C7(H7A,H7B), C6A(H6AA,H6AB), C7A(H7AA,H7AB), C6B(H6BA,H6BB),
 C7B(H7BA,H7BB)
2.c Aromatic/amide H refined with riding coordinates:
 C3(H3), C4(H4), C3A(H3A), C4A(H4A), C3B(H3B), C4B(H4B)
2.d Idealised tetrahedral OH refined as rotating group:
 O2(H2), O2A(H2AA), O2B(H2B)
;
_shelx_res_checksum              22389
_shelx_hkl_checksum              69484