4,4′-Bipyridine–cyano­acetic acid (1/2)

Crystals of the title adduct, C₁₀H₈N₂·2C₃H₃NO₂, were obtained from a methanol/water solution of cyano­acetic acid and 4,4′-bipyridine at room temperature. In the crystal structure, cyano­acetic acid and centrosymmetric 4,4′-bipyridine mol­ecules are linked by O—H...N hydrogen bonds to form three-component supra­molecular adducts. The acidic H atom is almost midway between the O and N atoms of the cyano­acetic acid and bipyridine mol­ecules, with O—H and N—H distances of 1.19 (3) and 1.39 (3) Å, respectively, so that the H-atom transfer is best regarded as partial. The three-component adducts are further inter­connected with neighboring mol­ecules by weak inter­molecular C—H...O and C—H...N hydrogen bonds and by π–π stacking inter­actions [centroid–centroid distance = 3.7200 (11) Å] to generate a three-dimensional supra­molecular structure.

Key indicators

• Single-crystal X-ray study
• T = 291 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.046
• wR factor = 0.133
• Data-to-parameter ratio = 13.3

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT353_ALERT_3_A Long    N-H Bond (0.87A)   N1     -   H1D    ...       1.39 Ang.

Author Response: The H1D was found in a Fourier map and its position was refined freely. Within the asymmetric unit, atom H1D is almost mid-way between atoms O1 and N1, so that the H-atom transfer is best regarded as partial.

Alert level C
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C3
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C6
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C8
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT480_ALERT_4_C Long H...A H-Bond Reported H7A    ..  N2      ..       2.92 Ang.
PLAT480_ALERT_4_C Long H...A H-Bond Reported H2     ..  O2      ..       2.62 Ang.
PLAT480_ALERT_4_C Long H...A H-Bond Reported H2     ..  N2      ..       2.75 Ang.

   1 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   8 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   4 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

A view of the title structure is shown in Fig. 1. The asymmetric unit consists of one cyanoacetic acid molecule and half a 4,4'-bipyridine molecule. The H1D was found in a Fourier map and its position was refined freely. Within the asymmetric unit, atom H1D is almost mid-way between atoms O1 and N1, so that the H-atom transfer is best regarded as partial. The distances of O1—H1D and N1—H1D are 1.19 (3) Å and 1.39 (3) Å, respectively, which are comparable with literature data (Farrell et al., 2002a,b). Cyanoacetic acid and 4,4'-bipyridine molecules are linked by these O—H···N hydrogen bonds to form 3-component supramolecular adducts.

The 3-compenent adducts interact with neigboring molecules via by weak intermolecular C—H···O and C—H···N hydrogen bonds, and by π-π stacking interactions. Within the asymmetric unit, the atoms C2 and C7 act as hydrogen-bond donors, via atoms H2, H2, and H7A, to atoms O2ⁱⁱ , N2ⁱⁱⁱ and N2ⁱ, respectively (symmetry operators: i = x + 1/2,-y + 1/2,z + 1/2; ii = x - 1,y,z -1; iii = x - 3/2,-y + 1/2,z - 1/2). The bond lengths and angles of the above three hydrogen bonds (Table 1) are comparable with literature data (Balakrishna et al., 2005; Wang et al., 2008). These hydrogen bonds, albeit rather weak, link the 3-component supramolecular adducts into a three-dimensional supramolecular structure, which is further stabilized by weak intermolecular π-π stacking interactions, formed by adjacent bipyridine rings (centroid–centroid distance = 3.7200 (11) Å) (Fig. 2 and Fig. 3).

Related literature

For similar partial proton transfer from a carbonic acid towards a nitrogen base, see: Farrell et al. (2002a,b); For C—H···O and C—H···N hydrogen bonds, see: Balakrishna et al. (2005); Wang et al. (2008).

S2. Experimental

Cyanoacetic acid (0.2 mmol) and 4,4'-bipyridine (0.2 mmol) were dissolved in methanol (5 ml) and water (1 ml) at room temperature. The single crystals of the title compound were obtained from the solution after ten days.

S3. Refinement

H1D was found in a difference Fourier map and was refined with U_iso(H) = 1.5U_eq(O). All other H atoms were positioned geometrically and treated as riding, with C—H bonding lengths constrained to 0.93 (aromatic CH) or 0.97 Å (methylene CH₂), and with U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures

	Fig. 1. A view of the title compound, showing 30% probability displacement ellipsoids. Symmetry code: (iv) -x, 1 - y,-z.
	Fig. 2. A view of the three-dimensional hydrogen-bonding pattern network.
	Fig. 3. View of the π-π interactions between bipyridine rings in the crystal structure of the title compound.

4,4'-Bipyridine–cyanoacetic acid (1/2)

Crystal data

C10H8N2·2C3H3NO2	F(000) = 340
Mr = 326.31	Dx = 1.332 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
a = 4.887 (2) Å	Cell parameters from 1445 reflections
b = 21.383 (10) Å	θ = 2.8–27.1°
c = 7.921 (4) Å	µ = 0.10 mm^−1
β = 100.664 (8)°	T = 291 K
V = 813.4 (7) Å^3	Block, colorless
Z = 2	0.34 × 0.26 × 0.19 mm

Data collection

Bruker SMART CCD area-detector diffractometer	1487 independent reflections
Radiation source: fine-focus sealed tube	1153 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.031
ϕ and ω scans	θmax = 25.5°, θmin = 2.8°
Absorption correction: multi-scan (SADABS; Bruker, 1997)	h = −5→5
Tmin = 0.952, Tmax = 0.982	k = −25→24
3537 measured reflections	l = −9→7

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.133	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0577P)^2 + 0.1963P] where P = (Fo^2 + 2Fc^2)/3
1487 reflections	(Δ/σ)max < 0.001
112 parameters	Δρmax = 0.16 e Å^−3
0 restraints	Δρmin = −0.15 e Å^−3

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

	x	y	z	Uiso*/Ueq
O1	0.9569 (3)	0.33450 (7)	0.35022 (19)	0.0763 (5)
H1D	0.779 (6)	0.3714 (12)	0.298 (3)	0.114*
O2	1.0674 (4)	0.40335 (8)	0.5596 (2)	0.1022 (6)
N1	0.5590 (3)	0.40726 (7)	0.21445 (19)	0.0595 (4)
N2	1.4242 (5)	0.21975 (10)	0.3693 (3)	0.1017 (7)
C1	0.3898 (4)	0.38664 (9)	0.0757 (3)	0.0729 (6)
H1	0.4196	0.3468	0.0354	0.087*
C2	0.1717 (4)	0.42138 (9)	−0.0118 (3)	0.0682 (6)
H2	0.0604	0.4052	−0.1100	0.082*
C3	0.1174 (3)	0.48036 (7)	0.04596 (19)	0.0464 (4)
C4	0.2939 (4)	0.50109 (9)	0.1930 (2)	0.0652 (5)
H4	0.2662	0.5402	0.2384	0.078*
C5	0.5109 (4)	0.46370 (9)	0.2722 (2)	0.0685 (6)
H5	0.6278	0.4787	0.3700	0.082*
C6	1.1058 (4)	0.35458 (9)	0.4903 (2)	0.0598 (5)
C7	1.3428 (4)	0.31156 (10)	0.5682 (3)	0.0707 (6)
H7A	1.5125	0.3360	0.5955	0.085*
H7B	1.3038	0.2948	0.6750	0.085*
C8	1.3896 (4)	0.25990 (10)	0.4580 (3)	0.0699 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0708 (9)	0.0714 (9)	0.0772 (9)	0.0193 (7)	−0.0112 (7)	−0.0097 (7)
O2	0.1424 (17)	0.0813 (11)	0.0760 (11)	0.0340 (11)	0.0021 (10)	−0.0164 (8)
N1	0.0558 (9)	0.0595 (9)	0.0611 (9)	0.0096 (7)	0.0053 (7)	0.0059 (7)
N2	0.1006 (16)	0.0809 (13)	0.1175 (17)	0.0300 (12)	0.0043 (13)	−0.0100 (12)
C1	0.0752 (14)	0.0532 (11)	0.0818 (14)	0.0146 (9)	−0.0073 (11)	−0.0079 (9)
C2	0.0700 (13)	0.0540 (10)	0.0708 (12)	0.0087 (9)	−0.0122 (10)	−0.0092 (9)
C3	0.0465 (9)	0.0460 (8)	0.0468 (8)	0.0003 (7)	0.0088 (7)	0.0027 (7)
C4	0.0685 (12)	0.0620 (11)	0.0592 (11)	0.0143 (9)	−0.0038 (9)	−0.0121 (8)
C5	0.0663 (13)	0.0744 (12)	0.0583 (11)	0.0123 (10)	−0.0051 (9)	−0.0077 (9)
C6	0.0676 (12)	0.0595 (10)	0.0536 (10)	0.0058 (9)	0.0143 (9)	0.0026 (8)
C7	0.0672 (13)	0.0827 (13)	0.0586 (11)	0.0084 (10)	0.0025 (9)	0.0020 (9)
C8	0.0613 (12)	0.0669 (12)	0.0773 (14)	0.0145 (10)	0.0021 (10)	0.0099 (10)

Geometric parameters (Å, º)

O1—C6	1.283 (2)	C3—C4	1.388 (2)
O1—H1D	1.19 (3)	C3—C3^i	1.498 (3)
O2—C6	1.209 (2)	C4—C5	1.382 (3)
N1—C1	1.323 (2)	C4—H4	0.9300
N1—C5	1.327 (2)	C5—H5	0.9300
N2—C8	1.142 (3)	C6—C7	1.518 (3)
C1—C2	1.377 (3)	C7—C8	1.452 (3)
C1—H1	0.9300	C7—H7A	0.9700
C2—C3	1.384 (2)	C7—H7B	0.9700
C2—H2	0.9300
C6—O1—H1D	109.8 (12)	C5—C4—H4	119.9
C1—N1—C5	117.80 (16)	C3—C4—H4	119.9
C1—N1—H1D	121.6 (10)	N1—C5—C4	122.65 (17)
C5—N1—H1D	120.6 (10)	N1—C5—H5	118.7
C1—N1—H1D	121.6 (10)	C4—C5—H5	118.7
C5—N1—H1D	120.6 (10)	O2—C6—O1	124.78 (19)
N1—C1—C2	123.03 (18)	O2—C6—C7	120.59 (19)
N1—C1—H1	118.5	O1—C6—C7	114.63 (17)
C2—C1—H1	118.5	C8—C7—C6	114.18 (17)
C1—C2—C3	120.22 (18)	C8—C7—H7A	108.7
C1—C2—H2	119.9	C6—C7—H7A	108.7
C3—C2—H2	119.9	C8—C7—H7B	108.7
C2—C3—C4	116.19 (16)	C6—C7—H7B	108.7
C2—C3—C3^i	121.79 (18)	H7A—C7—H7B	107.6
C4—C3—C3^i	122.02 (18)	N2—C8—C7	179.0 (2)
C5—C4—C3	120.11 (17)
C5—N1—C1—C2	1.2 (3)	C3^i—C3—C4—C5	−178.96 (19)
H1D—N1—C1—C2	−179.1 (12)	C1—N1—C5—C4	−0.3 (3)
N1—C1—C2—C3	−1.2 (3)	H1D—N1—C5—C4	−180.0 (12)
C1—C2—C3—C4	0.2 (3)	C3—C4—C5—N1	−0.7 (3)
C1—C2—C3—C3^i	179.8 (2)	O2—C6—C7—C8	−170.9 (2)
C2—C3—C4—C5	0.7 (3)	O1—C6—C7—C8	9.4 (3)

Symmetry code: (i) −x, −y+1, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7A···N2^ii	0.97	2.92	3.420 (3)	113
C2—H2···O2^iii	0.93	2.62	3.361 (3)	137
C2—H2···N2^iv	0.93	2.75	3.322 (3)	121
O1—H1D···N1	1.19 (3)	1.39 (3)	2.566 (2)	170 (2)

Symmetry codes: (ii) x+1/2, −y+1/2, z+1/2; (iii) x−1, y, z−1; (iv) x−3/2, −y+1/2, z−1/2.