# Supplementary Material (ESI) for Chemical Communications
# This journal is (c) The Royal Society of Chemistry 2010

data_global
_journal_name_full               Chem.Commun.

_journal_coden_Cambridge         0182
_journal_volume                  ?
_journal_page_first              ?
_journal_year                    ?

_publ_contact_author_name        'John Fossey'
_publ_contact_author_email       j.s.fossey@bham.ac.uk

_publ_section_title              
;
A Pyridinium Cation-I
Interaction Sensor for the Fluorescent
Detection of Alkyl Halides
;
loop_
_publ_author_name
W.Chen
S.A.Elfeky
Y.Nonne
L.Male
K.Ahmed
C.Amiable
P.Axe
S.Yamada
T.D.James
S.D.Bull
J.S.Fossey

# Attachment '2i-Final.cif.txt'

data_2i
_database_code_depnum_ccdc_archive 'CCDC 775629'
#TrackingRef '2i-Final.cif.txt'

# EPSRC National Crystallography Service Code: 2010src0259

_publ_section_comment            
;
The centre of the pyridinium molecule is located on an inversion centre
such that half the molecule is crystallographically unique.
Atoms C(10) and N(1) are present on the same site at 50 % occupancy each.
The R-factor and GOF are rather high. It is not clear why this is the
case, although the choice of space group was difficult and there are
several systematic absence violations. A refinement in space group P1
indicated the presence of a centre of inversion in the centre of the
N(1), C(10)-C(12) ring, with N(1) and C(10) occupying the same site at
50 % occupancy each. Refinements in several other space groups was
attempted, along with searches for merohedral twinning, but none of these
was significantly better than the refinement in Pbca, and PLATON always
indicated that the symmetry of the structure was consistent with the space
group Pbca.
;

_audit_creation_method           SHELXL-97
_chemical_name_systematic        
;
?
;
_chemical_name_common            ?
_chemical_melting_point          ?
_chemical_formula_moiety         'C23 H26 N, Br'
_chemical_formula_sum            'C23 H26 Br N'
_chemical_formula_weight         396.36

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'
Br Br -0.2901 2.4595 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'

_symmetry_cell_setting           Orthorhombic
_symmetry_space_group_name_H-M   'P b c a'

loop_
_symmetry_equiv_pos_as_xyz
'x, y, z'
'-x+1/2, -y, z+1/2'
'-x, y+1/2, -z+1/2'
'x+1/2, -y+1/2, -z'
'-x, -y, -z'
'x-1/2, y, -z-1/2'
'x, -y-1/2, z-1/2'
'-x-1/2, y-1/2, z'

_cell_length_a                   7.3748(2)
_cell_length_b                   10.0622(2)
_cell_length_c                   25.6743(8)
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_volume                     1905.21(9)
_cell_formula_units_Z            4
_cell_measurement_temperature    120(2)
_cell_measurement_reflns_used    29874
_cell_measurement_theta_min      2.91
_cell_measurement_theta_max      27.48

_exptl_crystal_description       'Cut Rod'
_exptl_crystal_colour            Colourless
_exptl_crystal_size_max          0.42
_exptl_crystal_size_mid          0.07
_exptl_crystal_size_min          0.06
_exptl_crystal_density_meas      ?
_exptl_crystal_density_diffrn    1.382
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             824
_exptl_absorpt_coefficient_mu    2.163
_exptl_absorpt_correction_type   Multi-scan
_exptl_absorpt_correction_T_min  0.4636
_exptl_absorpt_correction_T_max  0.8812
_exptl_absorpt_process_details   'SADABS 2007/2 (Sheldrick, G.M., 2007)'

_exptl_special_details           
;
SADABS was used to perform the Absorption correction
Estimated minimum and maximum transmission from
SADABS: 0.6176 and 0.7456
The given Tmin and Tmax were generated using the SHELX SIZE command.
;

_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 Roper CCD camera on \k-goniostat'
_diffrn_measurement_method       '\f & \w 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            22489
_diffrn_reflns_av_R_equivalents  0.0468
_diffrn_reflns_av_sigmaI/netI    0.0294
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_l_min       -33
_diffrn_reflns_limit_l_max       33
_diffrn_reflns_theta_min         3.17
_diffrn_reflns_theta_max         27.48
_reflns_number_total             2183
_reflns_number_gt                2047
_reflns_threshold_expression     >2\s(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    'SHELXS-97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_molecular_graphics    'Ortep-3 for Windows (Farrugia, 1997)'
_computing_publication_material  'WinGX (Farrugia, 1999)'

_refine_special_details          
;
Refinement of F^2^ against ALL reflections. The weighted R-factor wR and
goodness of fit S are based on F^2^, conventional R-factors R are based
on F, with F set to zero for negative F^2^. The threshold expression of
F^2^ > 2\s(F^2^) is used only for calculating R-factors(gt) etc. and is
not relevant to the choice of reflections for refinement. R-factors based
on F^2^ are statistically about twice as large as those based on F, and R-
factors based on ALL data will be even larger.
The centre of the pyridinium molecule is located on an inversion centre
such that half the molecule is crystallographically unique.
Atoms C(10) and N(1) are present on the same site at 50 % occupancy each.
The R-factor and GOF are rather high. It is not clear why this is the
case, although the choice of space group was difficult and there are
several systematic absence violations. A refinement in space group P1
indicated the presence of a centre of inversion in the centre of the
N(1), C(10)-C(12) ring, with N(1) and C(10) occupying the same site at
50 % occupancy each. Refinements in several other space groups was
attempted, along with searches for merohedral twinning, but none of these
was significantly better than the refinement in Pbca, and PLATON always
indicated that the symmetry of the structure was consistent with the space
group Pbca.
;

_refine_ls_structure_factor_coef Fsqd
_refine_ls_matrix_type           full
_refine_ls_weighting_scheme      calc
_refine_ls_weighting_details     
'calc w=1/[\s^2^(Fo^2^)+(0.0000P)^2^+21.9526P] where P=(Fo^2^+2Fc^2^)/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     none
_refine_ls_extinction_coef       ?
_refine_ls_number_reflns         2183
_refine_ls_number_parameters     115
_refine_ls_number_restraints     63
_refine_ls_R_factor_all          0.0986
_refine_ls_R_factor_gt           0.0950
_refine_ls_wR_factor_ref         0.2020
_refine_ls_wR_factor_gt          0.2009
_refine_ls_goodness_of_fit_ref   1.439
_refine_ls_restrained_S_all      1.419
_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
Br1 Br 0.0000 0.0000 0.0000 0.0257(3) Uani 1 2 d S . .
C1 C 0.3431(9) 0.1252(8) 0.2775(3) 0.0258(15) Uani 1 1 d . . .
H1 H 0.2549 0.1046 0.2518 0.031 Uiso 1 1 calc R . .
C2 C 0.3947(9) 0.0305(6) 0.3144(3) 0.0198(13) Uani 1 1 d . . .
H2 H 0.3411 -0.0554 0.3140 0.024 Uiso 1 1 calc R . .
C3 C 0.5245(8) 0.0619(6) 0.3517(2) 0.0174(12) Uani 1 1 d . . .
H3 H 0.5585 -0.0033 0.3766 0.021 Uiso 1 1 calc R . .
C4 C 0.6058(8) 0.1869(6) 0.3533(2) 0.0148(12) Uani 1 1 d . . .
C5 C 0.5519(9) 0.2808(6) 0.3164(2) 0.0174(12) Uani 1 1 d . . .
H5 H 0.6042 0.3670 0.3167 0.021 Uiso 1 1 calc R . .
C6 C 0.4225(10) 0.2490(7) 0.2791(2) 0.0230(14) Uani 1 1 d . . .
H6 H 0.3880 0.3140 0.2542 0.028 Uiso 1 1 calc R . .
C7 C 0.7489(9) 0.2154(5) 0.3936(2) 0.0149(12) Uani 1 1 d . . .
H7A H 0.7202 0.1659 0.4259 0.018 Uiso 1 1 calc R . .
H7B H 0.7479 0.3114 0.4020 0.018 Uiso 1 1 calc R . .
C8 C 0.9402(9) 0.1754(6) 0.3745(2) 0.0190(12) Uani 1 1 d U B .
H8A H 0.9361 0.0835 0.3608 0.023 Uiso 1 1 calc R . .
H8B H 0.9767 0.2349 0.3457 0.023 Uiso 1 1 calc R . .
C9 C 1.0824(9) 0.1831(6) 0.4178(3) 0.0204(12) Uani 1 1 d U . .
H9A H 1.2032 0.1617 0.4032 0.024 Uiso 1 1 calc R A 1
H9B H 1.0869 0.2749 0.4316 0.024 Uiso 1 1 calc R A 1
C10 C 1.0404(7) 0.0893(6) 0.4610(2) 0.0163(11) Uani 0.50 1 d PU B 1
N1 N 1.0404(7) 0.0893(6) 0.4610(2) 0.0163(11) Uani 0.50 1 d PU B 2
C11 C 1.0618(9) -0.0444(6) 0.4528(3) 0.0180(12) Uani 1 1 d U . .
H11 H 1.1070 -0.0755 0.4204 0.022 Uiso 1 1 calc R B 1
C12 C 0.9815(9) 0.1324(6) 0.5091(2) 0.0161(12) Uani 1 1 d U . .
H12 H 0.9711 0.2250 0.5157 0.019 Uiso 1 1 calc R B 1

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
Br1 0.0230(5) 0.0245(5) 0.0294(5) -0.0046(4) -0.0016(4) -0.0106(4)
C1 0.020(3) 0.037(4) 0.021(3) -0.006(3) -0.005(3) 0.008(3)
C2 0.022(3) 0.010(3) 0.028(3) -0.001(2) -0.004(3) -0.001(2)
C3 0.014(3) 0.020(3) 0.018(3) -0.001(2) -0.003(2) -0.001(2)
C4 0.018(3) 0.011(3) 0.014(3) -0.002(2) 0.004(2) 0.007(2)
C5 0.023(3) 0.011(3) 0.018(3) 0.000(2) 0.006(3) 0.006(2)
C6 0.029(3) 0.025(3) 0.016(3) -0.001(3) 0.003(3) 0.010(3)
C7 0.023(3) 0.006(2) 0.016(3) -0.003(2) 0.004(3) 0.003(2)
C8 0.017(3) 0.017(3) 0.022(3) -0.002(2) 0.001(2) 0.001(2)
C9 0.016(3) 0.019(3) 0.027(3) -0.005(2) 0.003(2) -0.003(3)
C10 0.013(2) 0.017(3) 0.019(2) -0.009(2) -0.005(2) 0.003(2)
N1 0.013(2) 0.017(3) 0.019(2) -0.009(2) -0.005(2) 0.003(2)
C11 0.019(3) 0.013(3) 0.023(3) -0.004(2) -0.004(2) 0.002(2)
C12 0.019(3) 0.020(3) 0.010(2) -0.008(2) -0.005(2) 0.006(2)

_geom_special_details            
;
All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes)
are estimated using the full covariance matrix. The cell s.u.'s are taken
into account individually in the estimation of s.u.'s in distances, angles
and torsion angles; correlations between s.u.'s in cell parameters are only
used when they are defined by crystal symmetry. An approximate (isotropic)
treatment of cell s.u.'s is used for estimating s.u.'s 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 C6 1.377(10) . ?
C1 C2 1.396(9) . ?
C1 H1 0.9500 . ?
C2 C3 1.391(8) . ?
C2 H2 0.9500 . ?
C3 C4 1.394(9) . ?
C3 H3 0.9500 . ?
C4 C5 1.396(8) . ?
C4 C7 1.506(9) . ?
C5 C6 1.388(9) . ?
C5 H5 0.9500 . ?
C6 H6 0.9500 . ?
C7 C8 1.547(9) . ?
C7 H7A 0.9900 . ?
C7 H7B 0.9900 . ?
C8 C9 1.529(9) . ?
C8 H8A 0.9900 . ?
C8 H8B 0.9900 . ?
C9 C10 1.490(9) . ?
C9 H9A 0.9900 . ?
C9 H9B 0.9900 . ?
C10 C11 1.371(8) . ?
C10 C12 1.379(8) . ?
C11 C12 1.357(9) 5_756 ?
C11 H11 0.9500 . ?
C12 C11 1.357(9) 5_756 ?
C12 H12 0.9500 . ?

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
C6 C1 C2 118.8(6) . . ?
C6 C1 H1 120.6 . . ?
C2 C1 H1 120.6 . . ?
C3 C2 C1 120.0(6) . . ?
C3 C2 H2 120.0 . . ?
C1 C2 H2 120.0 . . ?
C2 C3 C4 121.4(6) . . ?
C2 C3 H3 119.3 . . ?
C4 C3 H3 119.3 . . ?
C3 C4 C5 117.9(6) . . ?
C3 C4 C7 119.6(5) . . ?
C5 C4 C7 122.5(6) . . ?
C6 C5 C4 120.5(6) . . ?
C6 C5 H5 119.7 . . ?
C4 C5 H5 119.7 . . ?
C1 C6 C5 121.4(6) . . ?
C1 C6 H6 119.3 . . ?
C5 C6 H6 119.3 . . ?
C4 C7 C8 111.9(5) . . ?
C4 C7 H7A 109.2 . . ?
C8 C7 H7A 109.2 . . ?
C4 C7 H7B 109.2 . . ?
C8 C7 H7B 109.2 . . ?
H7A C7 H7B 107.9 . . ?
C9 C8 C7 112.5(5) . . ?
C9 C8 H8A 109.1 . . ?
C7 C8 H8A 109.1 . . ?
C9 C8 H8B 109.1 . . ?
C7 C8 H8B 109.1 . . ?
H8A C8 H8B 107.8 . . ?
C10 C9 C8 111.5(5) . . ?
C10 C9 H9A 109.3 . . ?
C8 C9 H9A 109.3 . . ?
C10 C9 H9B 109.3 . . ?
C8 C9 H9B 109.3 . . ?
H9A C9 H9B 108.0 . . ?
C11 C10 C12 118.9(6) . . ?
C11 C10 C9 118.9(5) . . ?
C12 C10 C9 122.2(5) . . ?
C12 C11 C10 120.1(6) 5_756 . ?
C12 C11 H11 119.9 5_756 . ?
C10 C11 H11 119.9 . . ?
C11 C12 C10 120.9(6) 5_756 . ?
C11 C12 H12 119.6 5_756 . ?
C10 C12 H12 119.6 . . ?

loop_
_geom_torsion_atom_site_label_1
_geom_torsion_atom_site_label_2
_geom_torsion_atom_site_label_3
_geom_torsion_atom_site_label_4
_geom_torsion
_geom_torsion_site_symmetry_1
_geom_torsion_site_symmetry_2
_geom_torsion_site_symmetry_3
_geom_torsion_site_symmetry_4
_geom_torsion_publ_flag
C6 C1 C2 C3 -0.2(10) . . . . ?
C1 C2 C3 C4 -0.1(10) . . . . ?
C2 C3 C4 C5 0.5(9) . . . . ?
C2 C3 C4 C7 -178.6(6) . . . . ?
C3 C4 C5 C6 -0.6(9) . . . . ?
C7 C4 C5 C6 178.4(6) . . . . ?
C2 C1 C6 C5 0.1(10) . . . . ?
C4 C5 C6 C1 0.3(10) . . . . ?
C3 C4 C7 C8 87.5(7) . . . . ?
C5 C4 C7 C8 -91.5(7) . . . . ?
C4 C7 C8 C9 -171.0(5) . . . . ?
C7 C8 C9 C10 62.2(7) . . . . ?
C8 C9 C10 C11 71.4(7) . . . . ?
C8 C9 C10 C12 -108.9(6) . . . . ?
C12 C10 C11 C12 2.6(10) . . . 5_756 ?
C9 C10 C11 C12 -177.7(6) . . . 5_756 ?
C11 C10 C12 C11 -2.6(10) . . . 5_756 ?
C9 C10 C12 C11 177.7(6) . . . 5_756 ?

_diffrn_measured_fraction_theta_max 0.999
_diffrn_reflns_theta_full        27.48
_diffrn_measured_fraction_theta_full 0.999
_refine_diff_density_max         0.525
_refine_diff_density_min         -0.810
_refine_diff_density_rms         0.135