Controlling the Cleavage of Carbon-Carbon Bonds To Generate α,α-Difluorobenzyl Carbanions for the Construction of Difluoromethylbenzenes.
Khatri, Hari R.; Han, Changho; Luong, Erica; Pan, Xiaoliang; Adam, Amna T.; Alshammari, Maali D.; Shao, Yihan; Colby, David A.; The Journal of organic chemistry 84 (2019) 11665–11675; doi:10.1021/acs.joc.9b01595

data_4034461
_publ_section_title
;
 Controlling the Cleavage of Carbon-Carbon Bonds To Generate
 \a,\a-Difluorobenzyl Carbanions for the Construction of
 Difluoromethylbenzenes.
;
_journal_issue                   18
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              11665
_journal_page_last               11675
_journal_paper_doi               10.1021/acs.joc.9b01595
_journal_volume                  84
_journal_year                    2019
_chemical_formula_sum            'C9 H6 F5 N O4'
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_space_group_crystal_system      monoclinic
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_space_group_name_Hall           '-C 2yc'
_space_group_name_H-M_alt        'C 1 2/c 1'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
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_cell_angle_alpha                90
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_cell_angle_gamma                90
_cell_formula_units_Z            8
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_cell_length_c                   12.0587(13)
_cell_measurement_reflns_used    9599
_cell_measurement_temperature    298(2)
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_cell_measurement_theta_min      2
_cell_volume                     2211.2(5)
_computing_cell_refinement       'HKL3000 (Otwinowski & Minor, 1997)'
_computing_data_collection       'Nonius Collect (Nonius, 1998)'
_computing_data_reduction        'HKL3000 (Otwinowski & Minor, 1997)'
_computing_structure_refinement
;  
SHELXL-2018/3 (Sheldrick, 2015, 2018), 
SHELXLE Rev946 (H\"ubschle et al., 2011)
;
_computing_structure_solution
;
 Direct methods (SIR2004, Burla et al., 2005)
;
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_diffrn_measured_fraction_theta_max 0.980
_diffrn_measurement_device_type  'Nonius Kappa CCD diffractometer'
_diffrn_measurement_method       '\w and \f scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0720
_diffrn_reflns_av_unetI/netI     0.0548
_diffrn_reflns_Laue_measured_fraction_full 0.993
_diffrn_reflns_Laue_measured_fraction_max 0.980
_diffrn_reflns_limit_h_max       24
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_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -15
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_diffrn_reflns_point_group_measured_fraction_full 0.993
_diffrn_reflns_point_group_measured_fraction_max 0.980
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_diffrn_source                   'fine focus X-ray tube'
_exptl_absorpt_coefficient_mu    0.186
_exptl_absorpt_correction_T_max  0.9635
_exptl_absorpt_correction_T_min  0.9375
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SCALEPACK (Otwinowski & Minor, 1997)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.725
_exptl_crystal_description       needle
_exptl_crystal_F_000             1152
_exptl_crystal_size_max          0.580
_exptl_crystal_size_mid          0.320
_exptl_crystal_size_min          0.200
_refine_diff_density_max         0.290
_refine_diff_density_min         -0.222
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_refine_ls_extinction_coef       0.0241(19)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2018/3 (Sheldrick 2018)'
_refine_ls_goodness_of_fit_ref   1.034
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     181
_refine_ls_number_reflns         2427
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.034
_refine_ls_R_factor_all          0.1159
_refine_ls_R_factor_gt           0.0539
_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^)+(0.0751P)^2^+2.0802P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1394
_refine_ls_wR_factor_ref         0.1732
_reflns_Friedel_coverage         0.000
_reflns_number_gt                1318
_reflns_number_total             2427
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            jo9b01595_si_003.cif
_cod_data_source_block           ch718
_cod_original_cell_volume        2211.3(4)
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               4034461
_shelx_shelxl_version_number     2018/3
_shelx_estimated_absorpt_t_min   0.900
_shelx_estimated_absorpt_t_max   0.964
_shelx_res_checksum              14748
_shelx_hkl_checksum              72874