N-Heterocyclic carbene-catalyzed enantioselective synthesis of functionalized cyclopentenes via alpha,beta-unsaturated acyl azoliums
Santigopal Mondal; Santhivardhana Reddy Yetra; Atanu Patra; Sunita S. Kunte; Rajesh G. Gonnade; Akkattu T. Biju; Chem.Commun. 50 (2014) 14539–; doi:10.1039/C4cc07433E

data_7115972
_publ_section_title
;
 N-Heterocyclic carbene-catalyzed enantioselective synthesis of
 functionalized cyclopentenes via alpha,beta-unsaturated acyl azoliums
;
_journal_name_full               Chem.Commun.
_journal_page_first              14539
_journal_paper_doi               10.1039/C4cc07433E
_journal_volume                  50
_journal_year                    2014
_chemical_absolute_configuration unk
_chemical_formula_moiety         'C20 H22 O8'
_chemical_formula_sum            'C20 H22 O8'
_chemical_formula_weight         390.38
_space_group_IT_number           5
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'C 2y'
_symmetry_space_group_name_H-M   'C 1 2 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                 121.607(6)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   20.4540(10)
_cell_length_b                   7.1698(3)
_cell_length_c                   15.6356(8)
_cell_measurement_reflns_used    3331
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      20.40
_cell_measurement_theta_min      2.34
_cell_volume                     1952.8(2)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_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  0.0436
_diffrn_reflns_av_sigmaI/netI    0.0487
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -25
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            11890
_diffrn_reflns_theta_full        26.00
_diffrn_reflns_theta_max         26.00
_diffrn_reflns_theta_min         1.53
_exptl_absorpt_coefficient_mu    0.103
_exptl_absorpt_correction_T_max  0.9938
_exptl_absorpt_correction_T_min  0.9609
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Bruker SADABS'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.328
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             824
_exptl_crystal_recrystallization_method
'Re-crystallisation from solvent: ethyl acetate-light petroleum ether'
_exptl_crystal_size_max          0.39
_exptl_crystal_size_mid          0.09
_exptl_crystal_size_min          0.06
_refine_diff_density_max         0.140
_refine_diff_density_min         -0.172
_refine_diff_density_rms         0.041
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   1.2(12)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.095
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     257
_refine_ls_number_reflns         3508
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.095
_refine_ls_R_factor_all          0.0722
_refine_ls_R_factor_gt           0.0515
_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^)+(0.0428P)^2^+0.2804P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0972
_refine_ls_wR_factor_ref         0.1054
_reflns_number_gt                2708
_reflns_number_total             3508
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c4cc07433e2.cif
_cod_data_source_block           sgm_sd_87
_cod_original_cell_volume        1952.84(16)
_cod_original_sg_symbol_H-M      C2
_cod_database_code               7115972