Copper-mediated oxidative [3 + 2]-annulation of nitroalkenes and pyridinium imines: efficient synthesis of 3-fluoro- and 3-nitro-pyrazolo[1,5-a]pyridines.
Motornov, Vladimir A.; Tabolin, Andrey A.; Nelyubina, Yulia V.; Nenajdenko, Valentine G.; Ioffe, Sema L.; Organic & biomolecular chemistry 18 (2020) 1436–1448; doi:10.1039/c9ob02668a

data_7157321
_publ_section_title
;
 Copper-mediated oxidative [3 + 2]-annulation of nitroalkenes and
 pyridinium imines: efficient synthesis of 3-fluoro- and
 3-nitro-pyrazolo[1,5-a]pyridines.
;
_journal_issue                   7
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              1436
_journal_page_last               1448
_journal_paper_doi               10.1039/c9ob02668a
_journal_volume                  18
_journal_year                    2020
_chemical_formula_moiety         'C12 H7 Br F N3'
_chemical_formula_sum            'C12 H7 Br F N3'
_chemical_formula_weight         292.12
_chemical_name_systematic
2-(4-Bromophenyl)-3-fluoro-pyrazolo[1,5-a]pyridazine
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2018/3
_audit_update_record
;
2019-12-02 deposited with the CCDC.	2020-01-24 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 98.1600(10)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   3.89430(10)
_cell_length_b                   25.4059(6)
_cell_length_c                   10.7978(3)
_cell_measurement_reflns_used    9978
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      34.92
_cell_measurement_theta_min      3.07
_cell_volume                     1057.50(5)
_computing_cell_refinement       'SAINT (Bruker, 2016)'
_computing_data_collection       '<i>APEX3</i> (Bruker, 2016)'
_computing_data_reduction        'SAINT (Bruker, 2016)'
_computing_molecular_graphics    'SHELXTL (Sheldrick, 2015b)'
_computing_publication_material  'SHELXTL (Sheldrick, 2015b)'
_computing_structure_refinement  'SHELXL-2018 (Sheldrick, 2015a)'
_computing_structure_solution    'SHELXS-2013 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker AXS D8 QUEST'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0481
_diffrn_reflns_av_unetI/netI     0.0238
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       38
_diffrn_reflns_limit_k_min       -38
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            34602
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         32.998
_diffrn_reflns_theta_min         2.490
_diffrn_source                   'X-Ray tube'
_exptl_absorpt_coefficient_mu    3.878
_exptl_absorpt_correction_T_max  0.7469
_exptl_absorpt_correction_T_min  0.5085
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS 2016/2 (Krause <i>et al.</i>, 2015)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.835
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             576
_exptl_crystal_size_max          0.58
_exptl_crystal_size_mid          0.19
_exptl_crystal_size_min          0.14
_refine_diff_density_max         0.533
_refine_diff_density_min         -0.727
_refine_diff_density_rms         0.076
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.060
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     182
_refine_ls_number_reflns         3957
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.060
_refine_ls_R_factor_all          0.0301
_refine_ls_R_factor_gt           0.0235
_refine_ls_shift/su_max          0.004
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0201P)^2^+0.6421P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0523
_refine_ls_wR_factor_ref         0.0554
_reflns_Friedel_coverage         0.000
_reflns_number_gt                3475
_reflns_number_total             3957
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c9ob02668a2.cif
_cod_data_source_block           VM1183
_cod_depositor_comments
'Adding full bibliography for 7157320--7157321.cif.'
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               7157321
_shelx_shelxl_version_number     2018/3
_shelx_estimated_absorpt_t_min   0.212
_shelx_estimated_absorpt_t_max   0.613
_shelx_res_checksum              72979