One-step synthesis of pyrido[1,2-a]benzimidazole derivatives by a novel multicomponent reaction of chloroacetonitrile, malononitrile, aromatic aldehyde, and pyridine.
Yan, Chao Guo; Wang, Qi Fang; Song, Xiao Kai; Sun, Jing; The Journal of organic chemistry 74 (2009) 710–718; doi:10.1021/jo802166t

data_4029487
_publ_section_title
;
 One-step synthesis of pyrido[1,2-a]benzimidazole derivatives by a novel
 multicomponent reaction of chloroacetonitrile, malononitrile, aromatic
 aldehyde, and pyridine.
;
_journal_issue                   2
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              710
_journal_page_last               718
_journal_paper_doi               10.1021/jo802166t
_journal_volume                  74
_journal_year                    2009
_chemical_formula_sum            'C24.5 H20.5 N4 O0.75'
_chemical_formula_weight         382.95
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_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                111.578(2)
_cell_angle_beta                 92.637(2)
_cell_angle_gamma                96.848(2)
_cell_formula_units_Z            4
_cell_length_a                   12.0489(16)
_cell_length_b                   13.7719(18)
_cell_length_c                   15.829(2)
_cell_measurement_temperature    296(2)
_cell_volume                     2413.6(5)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0325
_diffrn_reflns_av_sigmaI/netI    0.0634
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            17626
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.61
_exptl_absorpt_coefficient_mu    0.066
_exptl_absorpt_correction_T_max  0.9799
_exptl_absorpt_correction_T_min  0.9773
_exptl_crystal_density_diffrn    1.054
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             806
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.32
_exptl_crystal_size_min          0.31
_refine_diff_density_max         0.838
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_refine_ls_extinction_method     none
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_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     566
_refine_ls_number_reflns         8443
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_refine_ls_R_factor_all          0.1818
_refine_ls_R_factor_gt           0.1008
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1958P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
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_refine_ls_wR_factor_ref         0.3404
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_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo802166t_si_001.cif
_cod_data_source_block           3b
_cod_original_cell_volume        2413.6(6)
_cod_original_formula_sum        'C24.50 H20.50 N4 O0.75'
_cod_database_code               4029487