Facile synthesis of 3-substituted imidazo[1,2-a]pyridines through formimidamide chemistry
Sivappa, Rasapalli; Sammeta, Vamshikrishna Reddy; Huang, Yanchang; Golen, James A.; Savinov, Sergey N.; RSC Advances 9 (2019) 29659–; doi:10.1039/C9RA05841A

data_7233989
_publ_section_title
;
 Facile synthesis of 3-substituted imidazo[1,2-a]pyridines through
 formimidamide chemistry
;
_journal_issue                   51
_journal_name_full               'RSC Advances'
_journal_page_first              29659
_journal_paper_doi               10.1039/C9RA05841A
_journal_volume                  9
_journal_year                    2019
_chemical_formula_sum            'C13 H9 Br N2'
_chemical_formula_weight         273.13
_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'
_symmetry_space_group_name_Hall  'P 2c -2n'
_symmetry_space_group_name_H-M   'P n a 21'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014/6
_audit_update_record
;
2019-05-31 deposited with the CCDC.    2019-09-03 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   22.620(5)
_cell_length_b                   3.9660(8)
_cell_length_c                   12.201(3)
_cell_measurement_reflns_used    6616
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      25.25
_cell_measurement_theta_min      3.34
_cell_volume                     1094.6(4)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX3'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2014/6 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Bruker APEX-III Cmos'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0362
_diffrn_reflns_av_unetI/netI     0.0240
_diffrn_reflns_Laue_measured_fraction_full 0.998
_diffrn_reflns_Laue_measured_fraction_max 0.997
_diffrn_reflns_limit_h_max       27
_diffrn_reflns_limit_h_min       -27
_diffrn_reflns_limit_k_max       4
_diffrn_reflns_limit_k_min       -4
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            16352
_diffrn_reflns_point_group_measured_fraction_full 0.998
_diffrn_reflns_point_group_measured_fraction_max 0.998
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.303
_diffrn_reflns_theta_min         3.339
_exptl_absorpt_coefficient_mu    3.725
_exptl_absorpt_correction_T_max  0.562
_exptl_absorpt_correction_T_min  0.458
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.657
_exptl_crystal_description       BLOCK
_exptl_crystal_F_000             544
_exptl_crystal_size_max          0.300
_exptl_crystal_size_mid          0.120
_exptl_crystal_size_min          0.100
_refine_diff_density_max         0.338
_refine_diff_density_min         -0.433
_refine_diff_density_rms         0.040
_refine_ls_abs_structure_details
; 
 Refined as an inversion twin. 
;
_refine_ls_abs_structure_Flack   0.187(16)
_refine_ls_extinction_coef       0.0190(18)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   0.957
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     147
_refine_ls_number_reflns         1992
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.957
_refine_ls_R_factor_all          0.0338
_refine_ls_R_factor_gt           0.0266
_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^)+(0.0411P)^2^+0.4132P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0656
_refine_ls_wR_factor_ref         0.0693
_reflns_Friedel_coverage         0.905
_reflns_Friedel_fraction_full    0.999
_reflns_Friedel_fraction_max     0.998
_reflns_number_gt                1780
_reflns_number_total             1992
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c9ra05841a2.cif
_cod_data_source_block           UMD1745H_B
_cod_database_code               7233989
_shelx_estimated_absorpt_t_min   0.401
_shelx_estimated_absorpt_t_max   0.707
_shelxl_version_number           2014/6
_shelx_res_checksum              89444