Efficient and highly enantioselective construction of trifluoromethylated quaternary stereogenic centers via high-pressure mediated organocatalytic conjugate addition of nitromethane to β,β-disubstituted enones.
Kwiatkowski, Piotr; Cholewiak, Agnieszka; Kasztelan, Adrian; Organic letters 16 (2014) 5930–5933; doi:10.1021/ol502941d

data_1518264
_publ_section_title
;
 Efficient and highly enantioselective construction of trifluoromethylated
 quaternary stereogenic centers via high-pressure mediated organocatalytic
 conjugate addition of nitromethane to \b,\b-disubstituted enones.
;
_journal_issue                   22
_journal_name_full               'Organic letters'
_journal_page_first              5930
_journal_page_last               5933
_journal_paper_doi               10.1021/ol502941d
_journal_volume                  16
_journal_year                    2014
_chemical_formula_sum            'C15 H12 F3 N O3 S'
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_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   9.6417(2)
_cell_length_b                   10.2080(2)
_cell_length_c                   14.8652(3)
_cell_measurement_reflns_used    12358
_cell_measurement_temperature    100(2)
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_cell_measurement_theta_min      1.9904
_cell_volume                     1463.07(5)
_computing_cell_refinement
;
CrysAlisPro, Agilent Technologies,
Version 1.171.36.20 (release 27-06-2012 CrysAlis171 .NET)
(compiled Jul 11 2012,15:38:31)
;
_computing_data_collection
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CrysAlisPro, Agilent Technologies,
Version 1.171.36.20 (release 27-06-2012 CrysAlis171 .NET)
(compiled Jul 11 2012,15:38:31)
;
_computing_data_reduction
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CrysAlisPro, Agilent Technologies,
Version 1.171.36.20 (release 27-06-2012 CrysAlis171 .NET)
(compiled Jul 11 2012,15:38:31)
;
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Kuma KM4 CCD'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
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_diffrn_reflns_av_sigmaI/netI    0.0281
_diffrn_reflns_limit_h_max       14
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_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            21224
_diffrn_reflns_theta_full        33.14
_diffrn_reflns_theta_max         33.14
_diffrn_reflns_theta_min         2.42
_exptl_absorpt_coefficient_mu    0.269
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.99543
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_exptl_absorpt_process_details
;
CrysAlisPro, Agilent Technologies,
Version 1.171.36.20 (release 27-06-2012 CrysAlis171 .NET)
(compiled Jul 11 2012,15:38:31)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.559
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             704
_exptl_crystal_size_max          0.375
_exptl_crystal_size_mid          0.367
_exptl_crystal_size_min          0.14
_refine_diff_density_max         0.278
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_refine_diff_density_rms         0.045
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.02(6)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.041
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     254
_refine_ls_number_reflns         5590
_refine_ls_number_restraints     94
_refine_ls_restrained_S_all      1.033
_refine_ls_R_factor_all          0.0400
_refine_ls_R_factor_gt           0.0323
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0346P)^2^+0.1643P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0706
_refine_ls_wR_factor_ref         0.0746
_reflns_number_gt                4998
_reflns_number_total             5590
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol502941d_si_003.cif
_cod_data_source_block           pk526_1b
_cod_depositor_comments
'Adding full bibliography for 1518263--1518265.cif.'
_cod_original_sg_symbol_H-M      P212121
_cod_database_code               1518264