An unexpected directing effect in the asymmetric transfer hydrogenation of α,α-disubstituted ketones.
Soni, Rina; Collinson, John-Michael; Clarkson, Guy C.; Wills, Martin; Organic letters 13 (2011) 4304–4307; doi:10.1021/ol201643v

data_1502350
_publ_section_title
;
 An unexpected directing effect in the asymmetric transfer hydrogenation
 of \a,\a-disubstituted ketones.
;
_journal_issue                   16
_journal_name_full               'Organic letters'
_journal_page_first              4304
_journal_page_last               4307
_journal_paper_doi               10.1021/ol201643v
_journal_volume                  13
_journal_year                    2011
_chemical_absolute_configuration rmad
_chemical_formula_moiety         'C28 H32 O4 S'
_chemical_formula_sum            'C28 H32 O4 S'
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_space_group_IT_number           19
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_symmetry_space_group_name_Hall  'P 2ac 2ab'
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_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
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_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.43712(9)
_cell_length_b                   8.62914(9)
_cell_length_c                   36.4793(4)
_cell_measurement_reflns_used    26920
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      70.94
_cell_measurement_theta_min      3.63
_cell_volume                     2341.09(5)
_computing_cell_refinement       'CrysAlis RED, Oxford Diffraction Ltd'
_computing_data_collection       'CrysAlis CCD, Oxford Diffraction Ltd'
_computing_data_reduction        'CrysAlis RED, Oxford Diffraction Ltd'
_computing_molecular_graphics    'SHELXTL (Sheldrick, 1997)'
_computing_publication_material  'SHELXTL (Sheldrick, 1997)'
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_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 10.2833
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Oxford Diffraction Gemini R'
_diffrn_measurement_method       '\f & \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enhance (Mo) X-ray Source'
_diffrn_radiation_type           CuK\a
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_diffrn_reflns_av_R_equivalents  0.0285
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_diffrn_reflns_limit_h_min       -9
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_diffrn_reflns_limit_l_min       -44
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_diffrn_reflns_theta_full        71.08
_diffrn_reflns_theta_max         71.08
_diffrn_reflns_theta_min         4.85
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_exptl_absorpt_coefficient_mu    1.491
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_exptl_absorpt_correction_T_min  0.55
_exptl_absorpt_correction_type   multi-scan
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_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.318
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             992
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.16
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_refine_ls_abs_structure_details
'Flack H D (1983), Acta Cryst. A39, 876-881, 1890 Friedel pairs'
_refine_ls_abs_structure_Flack   0.004(11)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.062
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     300
_refine_ls_number_reflns         4506
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.062
_refine_ls_R_factor_all          0.0335
_refine_ls_R_factor_gt           0.0333
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0622P)^2^+0.4472P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0839
_refine_ls_wR_factor_ref         0.0841
_reflns_number_gt                4487
_reflns_number_total             4506
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol201643v_si_003.cif
_cod_data_source_block           rs7
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               1502350