Formal Diels-Alder reactions of chalcones and formylcyclopropanes catalyzed by chiral N-heterocyclic carbenes.
Lv, Hui; Mo, Junming; Fang, Xinqiang; Chi, Yonggui Robin; Organic letters 13 (2011) 5366–5369; doi:10.1021/ol202250s

data_1502503
_publ_section_title
;
 Formal Diels-Alder reactions of chalcones and formylcyclopropanes
 catalyzed by chiral N-heterocyclic carbenes.
;
_journal_issue                   19
_journal_name_full               'Organic letters'
_journal_page_first              5366
_journal_page_last               5369
_journal_paper_doi               10.1021/ol202250s
_journal_volume                  13
_journal_year                    2011
_chemical_absolute_configuration unk
_chemical_formula_moiety         'C27 H26 O4'
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_atom_sites_solution_hydrogens   geom
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_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   10.1002(2)
_cell_length_b                   13.2118(3)
_cell_length_c                   16.2598(3)
_cell_measurement_reflns_used    9946
_cell_measurement_temperature    103(2)
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_cell_measurement_theta_min      2.51
_cell_volume                     2169.74(8)
_computing_cell_refinement       'Bruker SAINT'
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_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
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_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      103(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
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_diffrn_reflns_limit_k_min       -16
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_diffrn_reflns_theta_max         33.87
_diffrn_reflns_theta_min         1.99
_exptl_absorpt_coefficient_mu    0.084
_exptl_absorpt_correction_T_max  0.9719
_exptl_absorpt_correction_T_min  0.9671
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_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.269
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_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0717P)^2^+0.1658P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0982
_refine_ls_wR_factor_ref         0.1077
_reflns_number_gt                4410
_reflns_number_total             4846
_reflns_threshold_expression     >2sigma(I)
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_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               1502503