The 1:1 adduct of 4-aminobenzoic acid with 4-aminobenzonitrile

The 1:1 adduct of 4-amino­benzoic acid (PABA) with 4-am-inobenzonitrile (PABN), C₇H₇NO₂·C₇H₆N₂, consists of a primary centrosymmetric cyclic hydrogen-bonded PABA dimer interaction [O...O 2.640 (3) Å] peripherally linked into chains by weaker hydrogen bonds via a head-to-tail PABN interaction [N...N 3.179 (4) and N...O 3.062 (4) Å], and is linked between the chains by amine-N (PABN) to amine-N (PABA) interactions [N...N 3.233 (5) Å]. No proton transfer occurs.

Computing details

Data collection: MSC/AFC Diffractometer Control Software (Molecular Structure Corporation, 1993); cell refinement: MSC/AFC Diffractometer Control Software; data reduction: TEXSAN (Molecular Structure Corporation, 1985); program(s) used to solve structure: SIR88 (Burla et al., 1989); program(s) used to refine structure: TEXSAN; software used to prepare material for publication: TEXSAN.

(I)

Crystal data

C7H7NO2·C7H6N2	Dx = 1.260 Mg m^−3
Mr = 255.28	Melting point = 479–481 K
Monoclinic, P21/c	Mo Kα radiation, λ = 0.7107 Å
a = 4.860 (3) Å	Cell parameters from 25 reflections
b = 32.543 (4) Å	θ = 10–20°
c = 8.538 (3) Å	µ = 0.09 mm^−1
β = 94.79 (4)°	T = 153 K
V = 1345.6 (8) Å^3	Prismatic, colourless
Z = 4	0.3 × 0.2 × 0.2 mm
F(000) = 536.00

Data collection

Rigaku AFC-7R diffractometer	Rint = 0.074
Radiation source: 12kW rotating anode X-ray tube	θmax = 25°
Graphite monochromator	h = 0→5
ω scans with profile analysis	k = 0→38
2723 measured reflections	l = −10→10
2372 independent reflections	3 standard reflections every 150 min
1614 reflections with I > 1.5σ(I)	intensity decay: 0.0%

Refinement

Refinement on F	H atoms treated by a mixture of independent and constrained refinement
Least-squares matrix: full	Weighting scheme based on measured s.u.'s
R[F^2 > 2σ(F^2)] = 0.045	(Δ/σ)max = 0.002
wR(F^2) = 0.043	Δρmax = 0.14 e Å^−3
S = 1.80	Δρmin = −0.16 e Å^−3
1614 reflections	Extinction correction: Zachariasen_type_2_Gaussian_isotropic
193 parameters	Extinction coefficient: 8.001
0 restraints

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

	x	y	z	Uiso*/Ueq
O1	0.3550 (3)	0.04485 (4)	0.0193 (2)	0.0517 (4)
O2	0.2661 (3)	−0.01288 (4)	0.1487 (2)	0.0544 (5)
N1	−0.4703 (4)	0.11097 (6)	0.5062 (2)	0.0595 (7)
N2	0.0888 (5)	0.10283 (7)	−0.2321 (3)	0.0646 (7)
N3	0.5519 (6)	0.29556 (6)	−0.1002 (3)	0.133 (1)
C1	0.0395 (4)	0.04765 (5)	0.2181 (2)	0.0411 (5)
C2	0.0082 (4)	0.09006 (5)	0.2065 (2)	0.0502 (6)
C3	−0.1637 (4)	0.11087 (5)	0.2983 (2)	0.0523 (7)
C4	−0.3106 (4)	0.08980 (6)	0.4072 (2)	0.0467 (6)
C5	−0.2797 (4)	0.04707 (6)	0.4189 (2)	0.0503 (6)
C6	−0.1088 (4)	0.02650 (5)	0.3247 (2)	0.0476 (6)
C7	0.2318 (4)	0.02670 (6)	0.1203 (2)	0.0435 (6)
C11	0.3737 (5)	0.22182 (7)	−0.1439 (3)	0.0695 (8)
C12	0.1585 (5)	0.21454 (7)	−0.2567 (3)	0.0709 (8)
C13	0.0615 (5)	0.17520 (6)	−0.2841 (2)	0.0652 (7)
C14	0.1776 (4)	0.14211 (6)	−0.2008 (2)	0.0526 (6)
C15	0.3976 (5)	0.14955 (6)	−0.0887 (2)	0.0617 (7)
C16	0.4934 (5)	0.18879 (7)	−0.0609 (2)	0.0723 (8)
C17	0.4746 (6)	0.26314 (7)	−0.1189 (3)	0.0935 (10)
H2	0.1072	0.1048	0.1334	0.060
H02	0.390 (5)	−0.0258 (6)	0.091 (2)	0.097 (9)
H3	−0.1832	0.1398	0.2881	0.063
H5	−0.3774	0.03219	0.4924	0.060
H6	−0.0921	−0.0025	0.3327	0.057
H10	−0.500 (4)	0.1406 (6)	0.481 (2)	0.078 (7)
H11	−0.574 (4)	0.0953 (6)	0.562 (2)	0.078 (9)
H12	0.0772	0.2368	−0.3158	0.085
H13	−0.0877	0.1707	−0.3613	0.079
H15	0.4815	0.1273	−0.0310	0.074
H16	0.6433	0.1934	0.0159	0.087
H20	0.134 (5)	0.0803 (6)	−0.162 (2)	0.096 (9)
H21	−0.057 (4)	0.0981 (6)	−0.276 (2)	0.056 (8)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0491 (9)	0.0533 (8)	0.0542 (9)	0.0077 (7)	0.0128 (7)	0.0026 (7)
O2	0.0514 (10)	0.0418 (7)	0.071 (1)	0.0076 (7)	0.0137 (8)	−0.0036 (7)
N1	0.056 (1)	0.061 (1)	0.064 (1)	0.003 (1)	0.018 (1)	−0.012 (1)
N2	0.067 (2)	0.056 (1)	0.068 (1)	−0.010 (1)	−0.007 (1)	−0.001 (1)
N3	0.188 (3)	0.078 (1)	0.135 (2)	−0.061 (2)	0.030 (2)	−0.018 (1)
C1	0.036 (1)	0.0443 (10)	0.042 (1)	0.0033 (9)	−0.0031 (8)	−0.0062 (9)
C2	0.051 (1)	0.0479 (10)	0.052 (1)	0.000 (1)	0.007 (1)	0.0024 (10)
C3	0.055 (1)	0.044 (1)	0.058 (1)	0.009 (1)	0.006 (1)	−0.0025 (9)
C4	0.035 (1)	0.056 (1)	0.048 (1)	0.0029 (10)	−0.0048 (9)	−0.0105 (9)
C5	0.044 (1)	0.053 (1)	0.055 (1)	−0.006 (1)	0.011 (1)	−0.001 (1)
C6	0.042 (1)	0.045 (1)	0.055 (1)	−0.0016 (10)	0.0022 (9)	−0.0011 (9)
C7	0.035 (1)	0.0448 (10)	0.049 (1)	0.0047 (9)	−0.0055 (9)	−0.0052 (9)
C11	0.082 (2)	0.063 (1)	0.067 (2)	−0.017 (1)	0.024 (1)	−0.012 (1)
C12	0.080 (2)	0.057 (1)	0.077 (2)	0.002 (1)	0.015 (1)	0.010 (1)
C13	0.064 (2)	0.062 (1)	0.069 (2)	−0.003 (1)	−0.002 (1)	0.004 (1)
C14	0.056 (1)	0.054 (1)	0.049 (1)	−0.004 (1)	0.0130 (9)	−0.0031 (9)
C15	0.058 (2)	0.067 (1)	0.060 (1)	−0.005 (1)	0.002 (1)	0.006 (1)
C16	0.070 (2)	0.080 (1)	0.067 (2)	−0.026 (1)	0.002 (1)	−0.003 (1)
C17	0.119 (3)	0.073 (1)	0.093 (2)	−0.034 (2)	0.030 (2)	−0.012 (2)

Geometric parameters (Å, º)

O1—C7	1.240 (3)	C4—C5	1.401 (4)
O2—C7	1.319 (3)	C5—C6	1.378 (4)
N1—C4	1.379 (4)	C11—C12	1.382 (5)
N2—C14	1.368 (4)	C11—C16	1.388 (5)
N3—C17	1.127 (4)	C11—C17	1.441 (4)
C1—C2	1.391 (4)	C12—C13	1.377 (4)
C1—C6	1.389 (4)	C13—C14	1.385 (4)
C1—C7	1.472 (4)	C14—C15	1.395 (4)
C2—C3	1.371 (4)	C15—C16	1.373 (4)
C3—C4	1.399 (4)
C2—C1—C6	118.6 (3)	O2—C7—C1	115.1 (3)
C2—C1—C7	119.3 (3)	C12—C11—C16	118.9 (3)
C6—C1—C7	122.1 (3)	C12—C11—C17	119.5 (4)
C1—C2—C3	121.2 (3)	C16—C11—C17	121.6 (4)
C2—C3—C4	120.5 (3)	C11—C12—C13	120.4 (4)
N1—C4—C3	120.5 (3)	C12—C13—C14	121.1 (4)
N1—C4—C5	121.0 (3)	N2—C14—C13	121.2 (3)
C3—C4—C5	118.4 (3)	N2—C14—C15	120.5 (3)
C4—C5—C6	120.4 (3)	C13—C14—C15	118.2 (3)
C1—C6—C5	120.9 (3)	C14—C15—C16	120.6 (3)
O1—C7—O2	122.1 (3)	C11—C16—C15	120.7 (4)
O1—C7—C1	122.7 (3)	N3—C17—C11	179.5 (6)