Histidine-Catalyzed Asymmetric Aldol Addition of Enolizable Aldehydes: Insights into its Mechanism
Ulf Scheffler; Rainer Mahrwald; Journal of Organic Chemistry 77 (2012) 2310–2330; doi:10.1021/jo202558f

data_4027031
_publ_section_title
;
 Histidine-Catalyzed Asymmetric Aldol Addition of Enolizable Aldehydes:
 Insights into its Mechanism
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              2310
_journal_page_last               2330
_journal_paper_doi               10.1021/jo202558f
_journal_volume                  77
_journal_year                    2012
_chemical_absolute_configuration rm
_chemical_formula_sum            'C32 H64 O16'
_chemical_formula_weight         704.83
_chemical_name_systematic
; 
 (3R, 4R, 5R)-3-Ethyl-3-methyltetrahydro-2H-pyran-2,4,5-triol 
;
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_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                 96.008(5)
_cell_angle_gamma                90.00
_cell_formula_units_Z            1
_cell_length_a                   11.0893(7)
_cell_length_b                   6.3495(3)
_cell_length_c                   13.2390(8)
_cell_measurement_reflns_used    1600
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      30.76
_cell_measurement_theta_min      3.14
_cell_volume                     927.06(9)
_computing_cell_refinement       'STOE X-AREA'
_computing_data_collection       'STOE X-AREA'
_computing_data_reduction        'STOE X-RED'
_computing_molecular_graphics    'PLATON, 1990'
_computing_publication_material  'PLATON, 1990'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.971
_diffrn_measured_fraction_theta_max 0.970
_diffrn_measurement_device_type  'STOE IPDS 2T'
_diffrn_measurement_method       'rotation method'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0562
_diffrn_reflns_av_sigmaI/netI    0.0539
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            6361
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         26.00
_diffrn_reflns_theta_min         2.53
_diffrn_standards_decay_%        'no decay'
_exptl_absorpt_coefficient_mu    0.100
_exptl_absorpt_correction_T_max  0.9881
_exptl_absorpt_correction_T_min  0.9517
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'PLATON, 1990'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.262
_exptl_crystal_description       plate
_exptl_crystal_F_000             384
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.12
_refine_diff_density_max         1.294
_refine_diff_density_min         -0.625
_refine_diff_density_rms         0.122
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.3(16)
_refine_ls_extinction_coef       0.049(13)
_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   1.085
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     222
_refine_ls_number_reflns         3018
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.085
_refine_ls_R_factor_all          0.0797
_refine_ls_R_factor_gt           0.0718
_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^)+(0.1608P)^2^+0.5741P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1959
_refine_ls_wR_factor_ref         0.2213
_reflns_number_gt                2828
_reflns_number_total             3018
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo202558f_23s34s29.cif
_cod_data_source_block           237i
_cod_database_code               4027031