Efficient C-B Bond Formation Promoted by N-Heterocyclic Carbenes: Synthesis of Tertiary and Quaternary B-Substituted Carbons through Metal-Free Catalytic Boron Conjugate Additions to Cyclic and Acyclic α,β-Unsaturated Carbonyls
Kang-sang Lee; Adil R. Zhugralin; Amir H. Hoveyda; Journal of the American Chemical Society 131 (2009) 7253–7255; doi:10.1021/ja902889s

data_4104467
_publ_section_title
;
 Efficient C-B Bond Formation Promoted by N-Heterocyclic Carbenes:
 Synthesis of Tertiary and Quaternary B-Substituted Carbons through
 Metal-Free Catalytic Boron Conjugate Additions to Cyclic and Acyclic
 \a,\b-Unsaturated Carbonyls
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              7253
_journal_page_last               7255
_journal_paper_doi               10.1021/ja902889s
_journal_volume                  131
_journal_year                    2009
_chemical_absolute_configuration syn
_chemical_formula_moiety         'C16 H25 B O4'
_chemical_formula_sum            'C16 H25 B O4'
_chemical_formula_weight         292.17
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.4202(8)
_cell_length_b                   10.7636(11)
_cell_length_c                   19.946(2)
_cell_measurement_reflns_used    9621
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      28.86
_cell_measurement_theta_min      2.78
_cell_volume                     1593.0(3)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Bruker SMART APEX CCD'
_diffrn_measurement_method       '0.3 deg wide \w exposures'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'normal-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0342
_diffrn_reflns_av_sigmaI/netI    0.0296
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_number            15283
_diffrn_reflns_theta_full        27.98
_diffrn_reflns_theta_max         27.98
_diffrn_reflns_theta_min         2.78
_exptl_absorpt_coefficient_mu    0.084
_exptl_absorpt_correction_T_max  0.9958
_exptl_absorpt_correction_T_min  0.9916
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.218
_exptl_crystal_density_method    none
_exptl_crystal_description       plate
_exptl_crystal_F_000             632
_exptl_crystal_size_max          0.10
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.374
_refine_diff_density_min         -0.134
_refine_diff_density_rms         0.048
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.1(7)
_refine_ls_extinction_coef       na
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.035
_refine_ls_hydrogen_treatment    refxyz
_refine_ls_matrix_type           full
_refine_ls_number_parameters     265
_refine_ls_number_reflns         3813
_refine_ls_number_restraints     25
_refine_ls_restrained_S_all      1.033
_refine_ls_R_factor_all          0.0406
_refine_ls_R_factor_gt           0.0377
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0654P)^2^+0.0673P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0938
_refine_ls_wR_factor_ref         0.0960
_reflns_number_gt                3583
_reflns_number_total             3813
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja902889s_si_003.cif
_cod_data_source_block           C16H25BO4
_cod_database_code               4104467