 
data_07skc0024p21c
 
_audit_creation_method            SHELXL-97
_chemical_name_systematic
;
Maleic Acid & 4-Methylimidazole
;
_chemical_name_common             ?
_chemical_melting_point           ?
_chemical_formula_moiety          ?
_chemical_formula_sum
 'C8 H10 N2 O4'
_chemical_formula_weight          198.18
 
loop_
 _atom_type_symbol
 _atom_type_description
 _atom_type_scat_dispersion_real
 _atom_type_scat_dispersion_imag
 _atom_type_scat_source
 'C'  'C'   0.0033   0.0016
 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
 'H'  'H'   0.0000   0.0000
 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
 'N'  'N'   0.0061   0.0033
 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
 'O'  'O'   0.0106   0.0060
 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
 
_symmetry_cell_setting            Monoclinic
_symmetry_space_group_name_H-M    P21/c
 
loop_
 _symmetry_equiv_pos_as_xyz
 'x, y, z'
 '-x, y+1/2, -z+1/2'
 '-x, -y, -z'
 'x, -y-1/2, z-1/2'
 
_cell_length_a                    5.5883(2)
_cell_length_b                    22.5838(12)
_cell_length_c                    7.3581(4)
_cell_angle_alpha                 90.00
_cell_angle_beta                  98.578(3)
_cell_angle_gamma                 90.00
_cell_volume                      918.24(8)
_cell_formula_units_Z             4
_cell_measurement_temperature     120(2)
_cell_measurement_reflns_used     2048
_cell_measurement_theta_min       2.91
_cell_measurement_theta_max       27.48
 
_exptl_crystal_description        block
_exptl_crystal_colour             colourless
_exptl_crystal_size_max           0.40
_exptl_crystal_size_mid           0.26
_exptl_crystal_size_min           0.14
_exptl_crystal_density_meas       ?
_exptl_crystal_density_diffrn     1.434
_exptl_crystal_density_method     'not measured'
_exptl_crystal_F_000              416
_exptl_absorpt_coefficient_mu     0.117
_exptl_absorpt_correction_type    multi-scan
_exptl_absorpt_correction_T_min   0.9549
_exptl_absorpt_correction_T_max   0.9839
_exptl_absorpt_process_details       'SADABS V2.10 (Sheldrick, G.M., 2003)' 
 
_exptl_special_details
;
 ?
;
 
_diffrn_ambient_temperature           120(2)
_diffrn_radiation_wavelength           0.71073
_diffrn_radiation_type                      MoK\a
_diffrn_radiation_source                  'Bruker-Nonius FR591 rotating anode'
_diffrn_radiation_monochromator    'graphite'
_diffrn_measurement_device_type  'Bruker-Nonius 95mm CCD camera on κ-goniostat'
_diffrn_measurement_method          'φ & ω scans'
_diffrn_detector_area_resol_mean   9.091
_diffrn_standards_number          ?
_diffrn_standards_interval_count  ?
_diffrn_standards_interval_time   ?
_diffrn_standards_decay_%         ?
_diffrn_reflns_number             10396
_diffrn_reflns_av_R_equivalents   0.0623
_diffrn_reflns_av_sigmaI/netI     0.0576
_diffrn_reflns_limit_h_min        -7
_diffrn_reflns_limit_h_max        6
_diffrn_reflns_limit_k_min        -29
_diffrn_reflns_limit_k_max        29
_diffrn_reflns_limit_l_min        -9
_diffrn_reflns_limit_l_max        9
_diffrn_reflns_theta_min          2.94
_diffrn_reflns_theta_max          27.48
_reflns_number_total              2102
_reflns_number_gt                 1467
_reflns_threshold_expression      >2sigma(I)
 
_computing_data_collection        
'COLLECT (Hooft, R.W.W., 1998)'
_computing_cell_refinement        
'DENZO (Otwinowski & Minor, 1997) & COLLECT (Hooft, R.W.W., 1998)'
#Although determined using DirAx, the cell is refined in the HKL
#package during data reduction
_computing_data_reduction         
'DENZO (Otwinowski & Minor, 1997) & COLLECT (Hooft, R.W.W., 1998)'  
_computing_structure_solution     ?
_computing_structure_refinement   'SHELXL-97 (Sheldrick, 1997)'
_computing_molecular_graphics     ?
_computing_publication_material   ?
 
_refine_special_details
;
 Refinement of F² against ALL reflections.  The weighted R-factor wR and
 goodness of fit S are based on F², conventional R-factors R are based
 on F, with F set to zero for negative F². The threshold expression of
 F² > 2sigma(F²) is used only for calculating R-factors(gt) etc. and is
 not relevant to the choice of reflections for refinement.  R-factors based
 on F² are statistically about twice as large as those based on F, and R-
 factors based on ALL data will be even larger.
;
 
_refine_ls_structure_factor_coef  Fsqd
_refine_ls_matrix_type            full
_refine_ls_weighting_scheme       calc
_refine_ls_weighting_details
 'calc w=1/[σ²(Fo²)+(0.0806P)²+0.0504P] where P=(Fo²+2Fc²)/3'
_atom_sites_solution_primary      direct
_atom_sites_solution_secondary    difmap
_atom_sites_solution_hydrogens    geom
_refine_ls_hydrogen_treatment     constr
_refine_ls_extinction_method      SHELXL
_refine_ls_extinction_coef        0.034(6)
_refine_ls_extinction_expression
 'Fc^*^=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4^'
_refine_ls_number_reflns          2102
_refine_ls_number_parameters      130
_refine_ls_number_restraints      0
_refine_ls_R_factor_all           0.0854
_refine_ls_R_factor_gt            0.0519
_refine_ls_wR_factor_ref          0.1421
_refine_ls_wR_factor_gt           0.1248
_refine_ls_goodness_of_fit_ref    1.045
_refine_ls_restrained_S_all       1.045
_refine_ls_shift/su_max           0.000
_refine_ls_shift/su_mean          0.000
 
loop_
 _atom_site_label
 _atom_site_type_symbol
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_U_iso_or_equiv
 _atom_site_adp_type
 _atom_site_occupancy
 _atom_site_symmetry_multiplicity
 _atom_site_calc_flag
 _atom_site_refinement_flags
 _atom_site_disorder_assembly
 _atom_site_disorder_group
C1 C -0.0335(3) 0.59343(8) 0.8364(3) 0.0221(4) Uani 1 1 d . . .
C2 C -0.2414(3) 0.55630(8) 0.7509(3) 0.0242(4) Uani 1 1 d . . .
H2 H -0.3935 0.5759 0.7319 0.029 Uiso 1 1 calc R . .
C3 C -0.2461(3) 0.49960(8) 0.6971(3) 0.0232(4) Uani 1 1 d . . .
H3 H -0.4022 0.4851 0.6487 0.028 Uiso 1 1 calc R . .
C4 C -0.0467(3) 0.45520(8) 0.7003(3) 0.0231(4) Uani 1 1 d . . .
O1A O 0.1792(2) 0.57073(6) 0.87320(18) 0.0272(4) Uani 1 1 d . . .
O1B O -0.0743(2) 0.64605(6) 0.87330(18) 0.0271(4) Uani 1 1 d . . .
O4A O 0.1716(2) 0.46934(6) 0.76915(19) 0.0289(4) Uani 1 1 d . . .
H4 H 0.1753 0.5049 0.8031 0.043 Uiso 1 1 calc R . .
O4B O -0.1001(2) 0.40549(6) 0.63697(19) 0.0300(4) Uani 1 1 d . . .
C22 C 0.4765(3) 0.35864(8) 0.8538(3) 0.0233(4) Uani 1 1 d . . .
H22 H 0.4931 0.3999 0.8767 0.028 Uiso 1 1 calc R . .
C24 C 0.5503(3) 0.26232(8) 0.8574(3) 0.0235(4) Uani 1 1 d . . .
C25 C 0.3311(3) 0.27224(8) 0.7540(3) 0.0249(4) Uani 1 1 d . . .
H25 H 0.2256 0.2430 0.6936 0.030 Uiso 1 1 calc R . .
C26 C 0.6886(4) 0.20680(9) 0.9047(3) 0.0301(5) Uani 1 1 d . . .
H26A H 0.5987 0.1732 0.8443 0.045 Uiso 1 1 calc R . .
H26B H 0.7117 0.2010 1.0382 0.045 Uiso 1 1 calc R . .
H26C H 0.8468 0.2096 0.8630 0.045 Uiso 1 1 calc R . .
N21 N 0.2898(3) 0.33271(7) 0.7530(2) 0.0242(4) Uani 1 1 d . . .
H21 H 0.1612 0.3508 0.6951 0.029 Uiso 1 1 calc R . .
N23 N 0.6366(3) 0.31758(7) 0.9176(2) 0.0231(4) Uani 1 1 d . . .
H23 H 0.7760 0.3243 0.9874 0.028 Uiso 1 1 calc R . .
 
loop_
 _atom_site_aniso_label
 _atom_site_aniso_U_11
 _atom_site_aniso_U_22
 _atom_site_aniso_U_33
 _atom_site_aniso_U_23
 _atom_site_aniso_U_13
 _atom_site_aniso_U_12
C1 0.0221(9) 0.0194(10) 0.0257(10) 0.0031(8) 0.0060(7) 0.0013(7)
C2 0.0198(9) 0.0224(10) 0.0300(11) 0.0042(8) 0.0021(7) 0.0014(7)
C3 0.0188(8) 0.0227(10) 0.0266(11) 0.0037(8) -0.0016(7) -0.0009(7)
C4 0.0214(9) 0.0219(10) 0.0254(10) 0.0001(8) 0.0018(7) -0.0036(7)
O1A 0.0184(6) 0.0221(7) 0.0396(8) -0.0042(6) -0.0006(5) 0.0006(5)
O1B 0.0278(7) 0.0182(7) 0.0353(8) -0.0004(6) 0.0048(6) 0.0021(5)
O4A 0.0207(6) 0.0173(7) 0.0472(9) -0.0078(6) -0.0004(5) 0.0007(5)
O4B 0.0294(7) 0.0207(7) 0.0382(9) -0.0046(6) -0.0004(6) -0.0028(6)
C22 0.0243(9) 0.0171(9) 0.0287(11) -0.0013(8) 0.0045(7) -0.0006(7)
C24 0.0300(10) 0.0179(10) 0.0243(11) 0.0004(7) 0.0102(7) -0.0023(7)
C25 0.0288(9) 0.0201(10) 0.0274(11) -0.0033(8) 0.0093(8) -0.0044(7)
C26 0.0384(11) 0.0197(10) 0.0336(12) -0.0010(8) 0.0101(8) 0.0036(8)
N21 0.0229(8) 0.0212(9) 0.0284(9) -0.0016(7) 0.0037(6) -0.0009(6)
N23 0.0233(8) 0.0186(8) 0.0271(9) -0.0016(6) 0.0028(6) -0.0008(6)
 
_geom_special_details
;
 All esds (except the esd in the dihedral angle between two l.s. planes)
 are estimated using the full covariance matrix.  The cell esds are taken
 into account individually in the estimation of esds in distances, angles
 and torsion angles; correlations between esds in cell parameters are only
 used when they are defined by crystal symmetry.  An approximate (isotropic)
 treatment of cell esds is used for estimating esds involving l.s. planes.
;
 
loop_
 _geom_bond_atom_site_label_1
 _geom_bond_atom_site_label_2
 _geom_bond_distance
 _geom_bond_site_symmetry_2
 _geom_bond_publ_flag
C1 O1B 1.247(2) . ?
C1 O1A 1.285(2) . ?
C1 C2 1.493(3) . ?
C2 C3 1.340(3) . ?
C2 H2 0.9500 . ?
C3 C4 1.496(3) . ?
C3 H3 0.9500 . ?
C4 O4B 1.235(2) . ?
C4 O4A 1.289(2) . ?
O4A H4 0.8400 . ?
C22 N21 1.323(2) . ?
C22 N23 1.325(2) . ?
C22 H22 0.9500 . ?
C24 C25 1.360(3) . ?
C24 N23 1.387(2) . ?
C24 C26 1.487(3) . ?
C25 N21 1.385(2) . ?
C25 H25 0.9500 . ?
C26 H26A 0.9800 . ?
C26 H26B 0.9800 . ?
C26 H26C 0.9800 . ?
N21 H21 0.8800 . ?
N23 H23 0.8800 . ?
 
loop_
 _geom_angle_atom_site_label_1
 _geom_angle_atom_site_label_2
 _geom_angle_atom_site_label_3
 _geom_angle
 _geom_angle_site_symmetry_1
 _geom_angle_site_symmetry_3
 _geom_angle_publ_flag
O1B C1 O1A 121.83(16) . . ?
O1B C1 C2 118.07(15) . . ?
O1A C1 C2 120.09(16) . . ?
C3 C2 C1 129.86(17) . . ?
C3 C2 H2 115.1 . . ?
C1 C2 H2 115.1 . . ?
C2 C3 C4 130.86(17) . . ?
C2 C3 H3 114.6 . . ?
C4 C3 H3 114.6 . . ?
O4B C4 O4A 122.33(17) . . ?
O4B C4 C3 117.75(16) . . ?
O4A C4 C3 119.92(16) . . ?
C4 O4A H4 109.5 . . ?
N21 C22 N23 108.85(16) . . ?
N21 C22 H22 125.6 . . ?
N23 C22 H22 125.6 . . ?
C25 C24 N23 105.77(16) . . ?
C25 C24 C26 131.54(17) . . ?
N23 C24 C26 122.69(16) . . ?
C24 C25 N21 107.50(16) . . ?
C24 C25 H25 126.3 . . ?
N21 C25 H25 126.3 . . ?
C24 C26 H26A 109.5 . . ?
C24 C26 H26B 109.5 . . ?
H26A C26 H26B 109.5 . . ?
C24 C26 H26C 109.5 . . ?
H26A C26 H26C 109.5 . . ?
H26B C26 H26C 109.5 . . ?
C22 N21 C25 108.46(15) . . ?
C22 N21 H21 125.8 . . ?
C25 N21 H21 125.8 . . ?
C22 N23 C24 109.41(16) . . ?
C22 N23 H23 125.3 . . ?
C24 N23 H23 125.3 . . ?
 
loop_
 _geom_hbond_atom_site_label_D
 _geom_hbond_atom_site_label_H
 _geom_hbond_atom_site_label_A
 _geom_hbond_distance_DH
 _geom_hbond_distance_HA
 _geom_hbond_distance_DA
 _geom_hbond_angle_DHA
 _geom_hbond_site_symmetry_A
O4A H4 O1A  0.84 1.57 2.4127(18) 178.0 .
N21 H21 O4B  0.88 1.91 2.761(2) 161.9 .
N23 H23 O1B  0.88 1.94 2.811(2) 169.6 3_667
N23 H23 O1A  0.88 2.58 3.0526(19) 114.6 3_667
 
_diffrn_measured_fraction_theta_max    0.997
_diffrn_reflns_theta_full              27.48
_diffrn_measured_fraction_theta_full   0.997
_refine_diff_density_max    0.290
_refine_diff_density_min   -0.376
_refine_diff_density_rms    0.099
