Nickel catalyzed synthesis of 4,4′-bichromenes/4,4′-bithiochromenes and their Atropisomerism
Muthuramalingam, Somasundaram; Garg, Jai Anand; Karthick, R.; Fox, Thomas; Blacque, Olivier; Venkatesan, Koushik; Ramanathan, Saiganesh; Kabilan, Senthamaraikannan; Balasubramanian, K. K.; Organic Chemistry Frontiers 6 (2019) 134–; doi:10.1039/C8QO00820E

data_1554419
_publ_section_title
;
 Nickel catalyzed synthesis of
 4,4&#x2032;-bichromenes/4,4&#x2032;-bithiochromenes and their
 Atropisomerism
;
_journal_issue                   1
_journal_name_full               'Organic Chemistry Frontiers'
_journal_page_first              134
_journal_paper_doi               10.1039/C8QO00820E
_journal_volume                  6
_journal_year                    2019
_chemical_formula_moiety         'C20 H18'
_chemical_formula_sum            'C20 H18'
_chemical_formula_weight         258.34
_space_group_crystal_system      orthorhombic
_space_group_IT_number           33
_space_group_name_Hall           'P 2c -2n'
_space_group_name_H-M_alt        'P n a 21'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014/7
_audit_update_record
;
2018-01-17 deposited with the CCDC.
2018-11-21 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   15.853(3)
_cell_length_b                   12.375(2)
_cell_length_c                   7.3639(12)
_cell_measurement_reflns_used    903
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      17.69
_cell_measurement_theta_min      2.57
_cell_volume                     1444.7(4)
_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-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.991
_diffrn_measured_fraction_theta_max 0.991
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0666
_diffrn_reflns_av_unetI/netI     0.0568
_diffrn_reflns_Laue_measured_fraction_full 0.991
_diffrn_reflns_Laue_measured_fraction_max 0.991
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -5
_diffrn_reflns_number            7027
_diffrn_reflns_point_group_measured_fraction_full 0.842
_diffrn_reflns_point_group_measured_fraction_max 0.841
_diffrn_reflns_theta_full        23.658
_diffrn_reflns_theta_max         23.658
_diffrn_reflns_theta_min         2.088
_exptl_absorpt_coefficient_mu    0.067
_exptl_absorpt_correction_T_max  0.992
_exptl_absorpt_correction_T_min  0.983
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS V2014/5(Bruker AXS.Inc)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.188
_exptl_crystal_description       Rectangular
_exptl_crystal_F_000             552
_exptl_crystal_size_max          0.250
_exptl_crystal_size_mid          0.220
_exptl_crystal_size_min          0.120
_refine_diff_density_max         0.135
_refine_diff_density_min         -0.124
_refine_diff_density_rms         0.033
_refine_ls_abs_structure_details
; 
 Flack x determined using 392 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259). 
;
_refine_ls_abs_structure_Flack   -5.9(10)
_refine_ls_extinction_coef       0.008(2)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2014/7 (Sheldrick 2014'
_refine_ls_goodness_of_fit_ref   1.011
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     182
_refine_ls_number_reflns         1836
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.011
_refine_ls_R_factor_all          0.0757
_refine_ls_R_factor_gt           0.0456
_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^)+(0.0423P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0892
_refine_ls_wR_factor_ref         0.1032
_reflns_Friedel_coverage         0.560
_reflns_Friedel_fraction_full    0.664
_reflns_Friedel_fraction_max     0.663
_reflns_number_gt                1290
_reflns_number_total             1836
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c8qo00820e2.cif
_cod_data_source_block           SSR1
_cod_database_code               1554419
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.983
_shelx_estimated_absorpt_t_max   0.992
_shelx_res_checksum              77850
_shelx_hkl_checksum              83852