α-Crotyl-α-difluoroboranyloxy-amides: Structure and Reactivity of Isolable Intermediates in Stereospecific α-Ketol Rearrangements.
Roßbach, Jan; Harms, Klaus; Koert, Ulrich; Organic letters 17 (2015) 3122–3125; doi:10.1021/acs.orglett.5b01427

data_1520317
_publ_section_title
;
 \a-Crotyl-\a-difluoroboranyloxy-amides: Structure and Reactivity of
 Isolable Intermediates in Stereospecific \a-Ketol Rearrangements.
;
_journal_issue                   12
_journal_name_full               'Organic letters'
_journal_page_first              3122
_journal_page_last               3125
_journal_paper_doi               10.1021/acs.orglett.5b01427
_journal_volume                  17
_journal_year                    2015
_chemical_formula_moiety         'C8 H11 Br O4'
_chemical_formula_sum            'C8 H11 Br O4'
_chemical_formula_weight         251.08
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                90
_cell_angle_beta                 94.753(3)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   8.8688(4)
_cell_length_b                   18.0772(8)
_cell_length_c                   6.0396(3)
_cell_measurement_reflns_used    5075
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      25.2291
_cell_measurement_theta_min      2.2532
_cell_volume                     964.96(8)
_computing_cell_refinement       'BRUKER SAINT'
_computing_data_collection       'BRUKER APEX2 2014.9-0'
_computing_data_reduction        'SAINT V8.34A (Bruker AXS Inc., 2013)'
_computing_molecular_graphics    'DIAMOND (Crystal Impact)'
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    'XT V2014/1 (Bruker AXS Inc., 2014)'
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 7.9
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker D8 QUEST area detector'
_diffrn_measurement_method       '\w and \f scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0419
_diffrn_reflns_av_unetI/netI     0.0221
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 1.000
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       21
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       7
_diffrn_reflns_limit_l_min       -7
_diffrn_reflns_number            12918
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 1.000
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.245
_diffrn_reflns_theta_min         2.253
_diffrn_source                   'microfocus sealed X-ray tube'
_exptl_absorpt_coefficient_mu    4.240
_exptl_absorpt_correction_T_max  0.85
_exptl_absorpt_correction_T_min  0.42
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details   'SADABS V2014/5 (Bruker AXS Inc.)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.728
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             504
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.802
_refine_diff_density_min         -0.362
_refine_diff_density_rms         0.067
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.052
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     124
_refine_ls_number_reflns         1751
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.052
_refine_ls_R_factor_all          0.0310
_refine_ls_R_factor_gt           0.0236
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0242P)^2^+0.6873P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0510
_refine_ls_wR_factor_ref         0.0538
_reflns_Friedel_coverage         0.000
_reflns_number_gt                1505
_reflns_number_total             1751
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ol5b01427_si_002.cif
_cod_data_source_block           JR21551_0m
_cod_depositor_comments
'Adding full bibliography for 1520305--1520319.cif.'
_cod_database_code               1520317
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.282
_shelx_estimated_absorpt_t_max   0.849
_shelx_res_checksum              18653
_shelx_hkl_checksum              94346