Chiral NHC-catalyzed oxodiene Diels-Alder reactions with alpha-chloroaldehyde bisulfite salts.
He, Ming; Beahm, Brendan J.; Bode, Jeffrey W.; Organic letters 10 (2008) 3817–3820; doi:10.1021/ol801502h

data_1504848
_publ_section_title
;
 Chiral NHC-catalyzed oxodiene Diels-Alder reactions with
 alpha-chloroaldehyde bisulfite salts.
;
_journal_issue                   17
_journal_name_full               'Organic letters'
_journal_page_first              3817
_journal_page_last               3820
_journal_paper_doi               10.1021/ol801502h
_journal_volume                  10
_journal_year                    2008
_chemical_absolute_configuration ad
_chemical_formula_sum            'C21 H19 Br O4'
_chemical_formula_weight         415.27
_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   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                   5.5454(17)
_cell_length_b                   18.341(5)
_cell_length_c                   18.463(5)
_cell_measurement_temperature    293(2)
_cell_volume                     1877.8(9)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.971
_diffrn_measured_fraction_theta_max 0.971
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'Omega scan'
_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  0.2305
_diffrn_reflns_av_sigmaI/netI    0.3782
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -22
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            13895
_diffrn_reflns_theta_full        26.47
_diffrn_reflns_theta_max         26.47
_diffrn_reflns_theta_min         2.21
_exptl_absorpt_coefficient_mu    2.212
_exptl_absorpt_correction_T_max  0.317
_exptl_absorpt_correction_T_min  0.178
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'psi scan'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.469
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             848
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.06
_exptl_crystal_size_min          0.06
_refine_diff_density_max         0.339
_refine_diff_density_min         -0.244
_refine_diff_density_rms         0.067
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.03(3)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.669
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     242
_refine_ls_number_reflns         3669
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.669
_refine_ls_R_factor_all          0.2831
_refine_ls_R_factor_gt           0.0521
_refine_ls_shift/su_max          0.100
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0600P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1083
_refine_ls_wR_factor_ref         0.1602
_reflns_number_gt                878
_reflns_number_total             3669
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol801502h_si_004.cif
_cod_data_source_block
(3S,4S)-Ethyl_3-benzyl-6-(4-bromophenyl)-2-oxo-3,4-dihydro-2H-pyran-4-carboxylate
_cod_original_cell_volume        1877.9(9)
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               1504848