Double diastereoselection in anti aldol reactions mediated by dicyclohexylchloroborane between an l-erythrulose derivative and chiral aldehydes.
Díaz-Oltra, Santiago; Ruiz, Purificación; Falomir, Eva; Murga, Juan; Carda, Miguel; Marco, J. Alberto; Organic & biomolecular chemistry 10 (2012) 6937–6944; doi:10.1039/c2ob25803j

data_7152553
_publ_section_title
;
 Double diastereoselection in anti aldol reactions mediated by
 dicyclohexylchloroborane between an l-erythrulose derivative and chiral
 aldehydes.
;
_journal_issue                   34
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              6937
_journal_page_last               6944
_journal_paper_doi               10.1039/c2ob25803j
_journal_volume                  10
_journal_year                    2012
_chemical_absolute_configuration rmad
_chemical_formula_moiety         'C41 H59 N O7 Si2'
_chemical_formula_sum            'C41 H59 N O7 Si2'
_chemical_formula_weight         734.07
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_Int_Tables_number      19
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_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                   14.2378(13)
_cell_length_b                   16.4937(16)
_cell_length_c                   19.1231(19)
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      0.123401
_cell_measurement_theta_min      0.0015
_cell_volume                     4490.8(7)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.1046
_diffrn_reflns_av_sigmaI/netI    0.1302
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            25922
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.63
_exptl_absorpt_coefficient_mu    0.123
_exptl_absorpt_correction_T_max  0.123401
_exptl_absorpt_correction_T_min  0.0015
_exptl_absorpt_correction_type   empirical
_exptl_crystal_colour            Colorless
_exptl_crystal_density_diffrn    1.086
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Prism
_exptl_crystal_F_000             1584
_exptl_crystal_size_max          0.21
_exptl_crystal_size_mid          0.17
_exptl_crystal_size_min          0.12
_refine_diff_density_max         0.299
_refine_diff_density_min         -0.232
_refine_diff_density_rms         0.034
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.1(2)
_refine_ls_extinction_coef       0.0008(4)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   0.997
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     504
_refine_ls_number_reflns         7906
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.997
_refine_ls_R_factor_all          0.2039
_refine_ls_R_factor_gt           0.0582
_refine_ls_shift/su_max          0.013
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0626P)^2^+1.4056P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1235
_refine_ls_wR_factor_ref         0.1856
_reflns_number_gt                3013
_reflns_number_total             7906
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c2ob25803j.txt
_cod_data_source_block           str805m
_cod_original_sg_symbol_H-M      P212121
_cod_database_code               7152553