N-Heterocyclic Carbene/Lewis Acid Dual Catalysis for the Divergent Construction of Enantiopure Bridged Lactones and Fused Indenes.
Wang, Zhan-Yong; Ding, Ya-Li; Li, Shi-Ning; Cheng, Ying; The Journal of organic chemistry 81 (2016) 11871–11881; doi:10.1021/acs.joc.6b02329

data_4037436
_publ_section_title
;
 N-Heterocyclic Carbene/Lewis Acid Dual Catalysis for the Divergent
 Construction of Enantiopure Bridged Lactones and Fused Indenes.
;
_journal_issue                   23
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              11871
_journal_page_last               11881
_journal_paper_doi               10.1021/acs.joc.6b02329
_journal_volume                  81
_journal_year                    2016
_chemical_absolute_configuration ad
_chemical_formula_sum            'C25 H19 Br O3'
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_cell_measurement_temperature    100(2)
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_computing_cell_refinement       'Bruker SAINT'
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_diffrn_measured_fraction_theta_max 0.992
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_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
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_diffrn_reflns_av_unetI/netI     0.0903
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_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            colorless
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_exptl_crystal_description       block
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_refine_ls_abs_structure_details
; 
 Refined as an inversion twin. 
;
_refine_ls_abs_structure_Flack   0.008(14)
_refine_ls_extinction_method     none
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_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details     'w=1/[\s^2^(Fo^2^)] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0970
_refine_ls_wR_factor_ref         0.0985
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_reflns_number_gt                3700
_reflns_number_total             4067
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            jo6b02329_si_002.cif
_cod_data_source_block           150626b_0m
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               4037436
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_shelx_estimated_absorpt_t_max   0.669
_shelx_res_checksum              36984
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