Novel semisquaraine regioisomers: isolation, divergent chemical reactivity and photophysical properties
Rekha R. Avirah; Kuthanapillil Jyothish; Cherumuttathu H. Suresh; Eringathodi Suresh; Danaboyina Ramaiah; Chem.Commun. 47 (2011) 12822–; doi:10.1039/c1cc15261k

data_7107098
_publ_section_title
;
 Novel semisquaraine regioisomers: isolation, divergent chemical
 reactivity and photophysical properties
;
_journal_name_full               Chem.Commun.
_journal_page_first              12822
_journal_paper_doi               10.1039/c1cc15261k
_journal_volume                  47
_journal_year                    2011
_chemical_formula_sum            'C20 H21 N O4'
_chemical_formula_weight         339.38
_chemical_name_systematic
;
?
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_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                 96.845(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.7932(8)
_cell_length_b                   8.7008(9)
_cell_length_c                   24.571(3)
_cell_measurement_reflns_used    1052
_cell_measurement_temperature    110(2)
_cell_measurement_theta_max      26.99
_cell_measurement_theta_min      2.49
_cell_volume                     1654.2(3)
_computing_cell_refinement       'BRUKER SMART'
_computing_data_collection       'BRUKER SMART'
_computing_data_reduction        'BRUKER SAINT'
_computing_molecular_graphics    ORTEP
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      110(2)
_diffrn_measured_fraction_theta_full 0.928
_diffrn_measured_fraction_theta_max 0.928
_diffrn_measurement_device_type  'BRUKER SMART APEX CCD DIFFRACTOMETER'
_diffrn_measurement_method       'OMEGA-PHI 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  0.0486
_diffrn_reflns_av_sigmaI/netI    0.0598
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       29
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            8006
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.67
_exptl_absorpt_coefficient_mu    0.095
_exptl_absorpt_correction_T_max  0.9962
_exptl_absorpt_correction_T_min  0.9831
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'BRUKER SADABS'
_exptl_crystal_colour            'WINE RED'
_exptl_crystal_density_diffrn    1.363
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       PLATES
_exptl_crystal_F_000             720
_exptl_crystal_size_max          0.18
_exptl_crystal_size_mid          0.11
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.412
_refine_diff_density_min         -0.350
_refine_diff_density_rms         0.076
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.263
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     230
_refine_ls_number_reflns         2903
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.263
_refine_ls_R_factor_all          0.1093
_refine_ls_R_factor_gt           0.0958
_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^)+(0.0723P)^2^+2.9841P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1988
_refine_ls_wR_factor_ref         0.2061
_reflns_number_gt                2536
_reflns_number_total             2903
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c1cc15261k.txt
_cod_data_source_block           1021parm(2e)
_cod_original_sg_symbol_H-M      P21/c
_cod_database_code               7107098