Acridinium isophthalate

The crystal structure of the title complex, C₁₃H₁₀N⁺·C₈H₅O₄⁻, confirmed the full proton transfer, i.e. protonation of the acridine N atom and deprotonation of one of the carboxyl­ic acid groups, in the isophthalic (1,3-benzene­di­carboxyl­ic) acid. In the title complex, isophthalate anions are linked via strong O—H...O bonds and weak C—H...O bonds into infinite chains along the a axis of the crystal. The acridinium cations are attached to the anionic chains via strong hydrogen bonds involving the carboxyl­ate groups of the isophthalate anion and the NH group of the acridinium cation.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.045
• wR factor = 0.120
• Data-to-parameter ratio = 12.0

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



ABSMU_01  Alert C The ratio of given/expected absorption coefficient lies
          outside the range 0.99 <> 1.01
          Calculated value of mu =     0.097
          Value of mu given      =     0.100


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 1 Alert Level C = Please check

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S1. Comment

Isophthalic acid is an organic dicarboxylic acid which crystallizes in space group P2₁/c, and forms supramolecular acid chains in its solid-state structure (Derissen, 1974). It is one of the organic acids that we are interested in for our research into the molecular self-assembly of carboxylic acids with N-aromatic complexes. As part of our analysis of the molecular interactions, the structure of the title complex, (I), was determined.

In (I), the cations and anions form a 1:1 cocrystal. The asymmetric unit and atomic numbering scheme of (I) is shown in Fig. 1. Supramolecular acid chains are formed along the a axis via strong O3—H101···O2 and weak C19—H19···O4 hydrogen bonds (Table 2). In addition, acridinium cations are joined to the acid chains (Fig. 2) by N1—H1···O1 hydrogen bonds (Table 2). Proton transfer occurs between the carboxylic acid group and the acridine N atom so that the aromatic N atom is positively charged while the corresponding carboxylic acid group is negatively charged (Table 1). Acridinium cations form infinite stacks along the a axis, the distance between the planes of adjacent acridinium cations being ca 3.5 Å.

S2. Experimental

Acridine and isophthalic acid were obtained from Aldrich. 33 mg of the acid and 36 mg of the base were used to dissolve into 15 ml of ethanol. Crystals of (I) were obtained by slow evaporation of the ethanol solution at the room temperature.

S3. Refinement

The H101 atom on the carboxylic acid group was located from the difference Fourier map and refined without restraint. All other H atoms were placed geometrically and allowed to ride on their parent atom during subsequent refinement, with an isotropic displacement parameter fixed at 1.2 times the U_eq value of the corresponding C or N atom.

Computing details

Data collection: CAD-4 Software (Enraf-Nonius, 1988); cell refinement: CAD-4 Software; data reduction: TEXSAN (Molecular Structure Corporation, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP (Sheldrick, 1993); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. The acridinium cation and isophthalate anion in the crystal structure of (I). Displacement ellipsoids are drawn at the 50% probability level (XP; Sheldrick, 1993).
	Fig. 2. Projection of the molecular packing of (I) onto the (010) plane showing isophthalate chains and acridinium stacks (CAMERON; Watkin et al., 1996).

Acridine–isophthalic acid

Crystal data

C13H10N^+·C8H5O4^−	Z = 2
Mr = 345.34	F(000) = 360
Triclinic, P1	Dx = 1.389 Mg m^−3
a = 8.5196 (9) Å	Mo Kα radiation, λ = 0.71073 Å
b = 9.144 (1) Å	Cell parameters from 25 reflections
c = 11.386 (4) Å	θ = 8.0–15.0°
α = 69.41 (2)°	µ = 0.10 mm^−1
β = 89.44 (1)°	T = 295 K
γ = 84.22 (1)°	Block, yellow
V = 825.8 (3) Å^3	0.50 × 0.25 × 0.15 mm

Data collection

Enraf-Nonius CAD-4 diffractometer	Rint = 0.023
Radiation source: fine-focus sealed tube	θmax = 24.9°, θmin = 3.5°
Graphite monochromator	h = −10→10
ω/2θ scans	k = −10→10
3032 measured reflections	l = 0→13
2874 independent reflections	3 standard reflections every 200 reflections
2054 reflections with I > 2σ(I)	intensity decay: none

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.045	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.120	H atoms treated by a mixture of independent and constrained refinement
S = 1.11	w = 1/[σ^2(Fo^2) + (0.0389P)^2 + 0.2511P] where P = (Fo^2 + 2Fc^2)/3
2874 reflections	(Δ/σ)max < 0.001
239 parameters	Δρmax = 0.16 e Å^−3
0 restraints	Δρmin = −0.27 e Å^−3

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic)

treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. 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 > σ(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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
C1	0.1914 (2)	0.5425 (2)	0.05355 (18)	0.0397 (5)
C2	0.0934 (3)	0.5486 (3)	0.1533 (2)	0.0524 (6)
H2	0.0545	0.4578	0.2067	0.063*
C3	0.0565 (3)	0.6866 (3)	0.1706 (3)	0.0683 (7)
H3	−0.0065	0.6896	0.2371	0.082*
C4	0.1114 (4)	0.8249 (3)	0.0903 (3)	0.0736 (8)
H4	0.0851	0.9185	0.1043	0.088*
C5	0.2023 (3)	0.8243 (3)	−0.0074 (3)	0.0675 (7)
H5	0.2366	0.9176	−0.0608	0.081*
C6	0.2458 (2)	0.6823 (2)	−0.02912 (19)	0.0466 (5)
C7	0.3398 (3)	0.6711 (3)	−0.1264 (2)	0.0544 (6)
H7	0.3776	0.7612	−0.1820	0.065*
C8	0.3784 (2)	0.5298 (3)	−0.14236 (19)	0.0476 (5)
C9	0.4724 (3)	0.5118 (4)	−0.2416 (2)	0.0694 (7)
H9	0.5110	0.5992	−0.3001	0.083*
C10	0.5058 (3)	0.3697 (5)	−0.2515 (3)	0.0838 (10)
H10	0.5667	0.3598	−0.3171	0.101*
C11	0.4492 (3)	0.2358 (4)	−0.1633 (3)	0.0792 (9)
H11	0.4737	0.1385	−0.1715	0.095*
C12	0.3600 (3)	0.2459 (3)	−0.0673 (2)	0.0604 (6)
H12	0.3239	0.1564	−0.0095	0.072*
C13	0.3222 (2)	0.3933 (2)	−0.05556 (19)	0.0419 (5)
C14	0.1152 (2)	0.9353 (2)	0.36771 (18)	0.0371 (4)
C15	−0.0485 (2)	0.9496 (2)	0.36344 (18)	0.0387 (5)
H15	−0.1037	1.0405	0.3084	0.046*
C16	−0.1309 (2)	0.8297 (2)	0.44059 (18)	0.0393 (5)
C17	−0.0475 (3)	0.6944 (2)	0.52102 (19)	0.0492 (5)
H17	−0.1012	0.6123	0.5715	0.059*
C18	0.1157 (3)	0.6809 (3)	0.5266 (2)	0.0548 (6)
H18	0.1711	0.5899	0.5812	0.066*
C19	0.1963 (2)	0.8011 (2)	0.4518 (2)	0.0487 (5)
H19	0.3059	0.7922	0.4578	0.058*
C20	0.2007 (2)	1.0627 (2)	0.2786 (2)	0.0430 (5)
O1	0.11318 (16)	1.16990 (17)	0.19597 (15)	0.0576 (5)
O2	0.34385 (17)	1.0593 (2)	0.28384 (17)	0.0726 (5)
O3	−0.36907 (18)	0.98302 (19)	0.36458 (17)	0.0673 (5)
H101	−0.493 (4)	0.986 (3)	0.363 (3)	0.102 (9)*
O4	−0.38280 (19)	0.7372 (2)	0.49132 (16)	0.0697 (5)
C21	−0.3057 (2)	0.8430 (3)	0.43635 (19)	0.0460 (5)
N1	0.23126 (18)	0.40482 (19)	0.03912 (15)	0.0408 (4)
H1	0.1980	0.3213	0.0916	0.049*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C14	0.0353 (10)	0.0420 (11)	0.0359 (10)	−0.0065 (8)	0.0056 (8)	−0.0155 (9)
O3	0.0354 (9)	0.0595 (10)	0.0841 (13)	−0.0094 (7)	0.0016 (8)	0.0044 (9)
O1	0.0406 (8)	0.0522 (9)	0.0624 (10)	−0.0115 (7)	0.0028 (7)	0.0035 (8)
C16	0.0400 (10)	0.0440 (11)	0.0346 (10)	−0.0090 (8)	0.0044 (8)	−0.0133 (9)
C20	0.0368 (11)	0.0458 (12)	0.0462 (12)	−0.0089 (9)	0.0045 (9)	−0.0150 (10)
C17	0.0526 (13)	0.0466 (12)	0.0408 (12)	−0.0136 (10)	0.0058 (10)	−0.0040 (10)
O4	0.0526 (10)	0.0711 (11)	0.0677 (11)	−0.0270 (8)	0.0117 (8)	0.0027 (9)
C15	0.0384 (11)	0.0386 (11)	0.0377 (11)	−0.0052 (8)	0.0016 (8)	−0.0112 (9)
O2	0.0326 (9)	0.0817 (12)	0.0804 (12)	−0.0141 (8)	0.0030 (8)	0.0024 (10)
C19	0.0393 (11)	0.0524 (13)	0.0506 (13)	−0.0007 (9)	−0.0002 (10)	−0.0145 (10)
C21	0.0442 (11)	0.0532 (13)	0.0367 (11)	−0.0141 (10)	0.0078 (9)	−0.0087 (10)
C18	0.0517 (13)	0.0463 (13)	0.0528 (13)	−0.0012 (10)	−0.0043 (11)	−0.0013 (10)
N1	0.0403 (9)	0.0406 (9)	0.0386 (9)	−0.0108 (7)	0.0080 (7)	−0.0088 (7)
C1	0.0393 (10)	0.0415 (12)	0.0372 (11)	−0.0033 (9)	−0.0014 (8)	−0.0125 (9)
C13	0.0340 (10)	0.0536 (13)	0.0421 (11)	−0.0073 (9)	0.0041 (9)	−0.0212 (10)
C6	0.0516 (12)	0.0421 (12)	0.0414 (12)	−0.0037 (9)	−0.0055 (10)	−0.0090 (9)
C8	0.0401 (11)	0.0657 (15)	0.0344 (11)	−0.0134 (10)	0.0043 (9)	−0.0124 (10)
C2	0.0499 (12)	0.0633 (15)	0.0434 (12)	−0.0009 (11)	0.0060 (10)	−0.0194 (11)
C7	0.0587 (14)	0.0504 (13)	0.0432 (13)	−0.0169 (10)	−0.0008 (11)	0.0001 (10)
C9	0.0527 (14)	0.114 (2)	0.0395 (13)	−0.0197 (14)	0.0138 (11)	−0.0226 (14)
C12	0.0554 (14)	0.0638 (16)	0.0724 (17)	−0.0088 (11)	0.0059 (12)	−0.0364 (13)
C5	0.0873 (19)	0.0416 (13)	0.0670 (17)	−0.0020 (12)	−0.0231 (15)	−0.0115 (12)
C3	0.0666 (16)	0.083 (2)	0.0591 (16)	0.0171 (14)	−0.0077 (13)	−0.0366 (15)
C4	0.091 (2)	0.0623 (17)	0.0710 (18)	0.0233 (15)	−0.0254 (16)	−0.0352 (15)
C10	0.0548 (16)	0.150 (3)	0.0654 (19)	−0.0049 (18)	0.0110 (14)	−0.064 (2)
C11	0.0625 (16)	0.108 (2)	0.093 (2)	−0.0015 (16)	0.0070 (16)	−0.070 (2)

Geometric parameters (Å, º)

C14—C19	1.384 (3)	C13—C12	1.406 (3)
C14—C15	1.388 (3)	C13—C8	1.417 (3)
C14—C20	1.497 (3)	C6—C7	1.387 (3)
O3—H101	1.06 (3)	C6—C5	1.419 (3)
O1—C20	1.272 (2)	C8—C7	1.375 (3)
C16—C17	1.383 (3)	C8—C9	1.425 (3)
C16—C15	1.390 (3)	C2—C3	1.351 (3)
C16—C21	1.482 (3)	C2—H2	0.9300
O2—C20	1.219 (2)	C7—H7	0.9300
O3—C21	1.316 (3)	C9—C10	1.345 (4)
C17—C18	1.383 (3)	C9—H9	0.9300
C17—H17	0.9300	C12—C11	1.350 (4)
O4—C21	1.205 (2)	C12—H12	0.9300
C15—H15	0.9300	C5—C4	1.351 (4)
C19—C18	1.374 (3)	C5—H5	0.9300
C19—H19	0.9300	C3—C4	1.397 (4)
C18—H18	0.9300	C3—H3	0.9300
N1—C1	1.336 (2)	C4—H4	0.9300
N1—C13	1.349 (3)	C10—C11	1.409 (5)
N1—H1	0.8600	C10—H10	0.9300
C1—C6	1.414 (3)	C11—H11	0.9300
C1—C2	1.417 (3)
C19—C14—C15	119.20 (19)	C7—C6—C1	117.49 (19)
C19—C14—C20	121.34 (18)	C7—C6—C5	124.1 (2)
C15—C14—C20	119.43 (18)	C1—C6—C5	118.4 (2)
C21—O3—H101	110.1 (16)	C7—C8—C13	118.58 (19)
C17—C16—C15	119.10 (18)	C7—C8—C9	123.8 (2)
C17—C16—C21	119.63 (18)	C13—C8—C9	117.6 (2)
C15—C16—C21	121.26 (18)	C3—C2—C1	119.9 (2)
O2—C20—O1	123.42 (19)	C3—C2—H2	120.1
O2—C20—C14	121.59 (19)	C1—C2—H2	120.1
O1—C20—C14	114.95 (17)	C8—C7—C6	121.4 (2)
C18—C17—C16	120.23 (19)	C8—C7—H7	119.3
C18—C17—H17	119.9	C6—C7—H7	119.3
C16—C17—H17	119.9	C10—C9—C8	120.7 (3)
C14—C15—C16	120.72 (18)	C10—C9—H9	119.6
C14—C15—H15	119.6	C8—C9—H9	119.6
C16—C15—H15	119.6	C11—C12—C13	119.2 (3)
C18—C19—C14	120.33 (19)	C11—C12—H12	120.4
C18—C19—H19	119.8	C13—C12—H12	120.4
C14—C19—H19	119.8	C4—C5—C6	120.4 (3)
O4—C21—O3	123.1 (2)	C4—C5—H5	119.8
O4—C21—C16	124.1 (2)	C6—C5—H5	119.8
O3—C21—C16	112.81 (17)	C2—C3—C4	121.1 (3)
C19—C18—C17	120.4 (2)	C2—C3—H3	119.5
C19—C18—H18	119.8	C4—C3—H3	119.5
C17—C18—H18	119.8	C5—C4—C3	120.8 (2)
C1—N1—C13	121.77 (17)	C5—C4—H4	119.6
C1—N1—H1	119.1	C3—C4—H4	119.6
C13—N1—H1	119.1	C9—C10—C11	120.4 (3)
N1—C1—C6	121.01 (19)	C9—C10—H10	119.8
N1—C1—C2	119.56 (19)	C11—C10—H10	119.8
C6—C1—C2	119.43 (19)	C12—C11—C10	121.4 (3)
N1—C13—C12	119.6 (2)	C12—C11—H11	119.3
N1—C13—C8	119.74 (19)	C10—C11—H11	119.3
C12—C13—C8	120.6 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H101···O2^i	1.06 (3)	1.61 (3)	2.562 (2)	147 (3)
N1—H1···O1^ii	0.86	1.70	2.553 (2)	173
C19—H19···O4^iii	0.93	2.66	3.582 (3)	174

Symmetry codes: (i) x−1, y, z; (ii) x, y−1, z; (iii) x+1, y, z.