An Unusual Reaction of Benzalaminoacetals in Trifluoroacetic Acid: Facile Synthesis of 2-Benzylpyrazines
John Kallikat Augustine; Yanjerappa Arthoba Naik; Ashis Baran Mandal; Umesha Kundapur; Journal of Organic Chemistry 73 (2008) 1176–1179; doi:10.1021/jo702448a

data_4023247
_publ_section_title
;
 An Unusual Reaction of Benzalaminoacetals in Trifluoroacetic
 Acid: Facile Synthesis of 2-Benzylpyrazines
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              1176
_journal_page_last               1179
_journal_paper_doi               10.1021/jo702448a
_journal_volume                  73
_journal_year                    2008
_chemical_absolute_configuration unk
_chemical_formula_moiety         'C11 H9 N3 O2'
_chemical_formula_sum            'C11 H9 N3 O2'
_chemical_formula_weight         215.21
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   4.5573(4)
_cell_length_b                   10.7409(9)
_cell_length_c                   21.1615(17)
_cell_measurement_reflns_used    6161
_cell_measurement_temperature    294(2)
_cell_measurement_theta_max      27.0
_cell_measurement_theta_min      2.7
_cell_volume                     1035.84(15)
_computing_cell_refinement       'SAINT (Bruker, 2001)'
_computing_data_collection       'SMART (Bruker, 2001)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    'SHELXTL/PC (Sheldrick, 1990)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      294(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device       'Bruker SMART APEX CCD area-detector'
_diffrn_measurement_device_type  'CCD Area Detector'
_diffrn_measurement_method       '\w scan'
_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  0.0199
_diffrn_reflns_av_sigmaI/netI    0.0122
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       25
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            9847
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.92
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.099
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            'dark brown'
_exptl_crystal_density_diffrn    1.380
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             448
_exptl_crystal_size_max          0.22
_exptl_crystal_size_mid          0.18
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.111
_refine_diff_density_min         -0.154
_refine_diff_density_rms         0.037
_refine_ls_extinction_coef       0.040(6)
_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   1.110
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     146
_refine_ls_number_reflns         1106
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.110
_refine_ls_R_factor_all          0.0370
_refine_ls_R_factor_gt           0.0355
_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^)+(0.0611P)^2^+0.0632P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0976
_refine_ls_wR_factor_ref         0.0998
_reflns_number_gt                1057
_reflns_number_total             1106
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            jo702448a-File004.cif
_cod_data_source_block           ab73m
_cod_database_code               4023247