The title compound, {[Ag(C
4H
6NO
4)(C
4H
5N
3)]·H
2O}
n, was synthesized by the reaction of silver(I) nitrate with 2-aminopyrimidine and iminodiacetic acid. X-ray analysis reveals that the crystal structure contains a one-dimensional ladder-like Ag
I coordination polymer and that N—H
O and O—H
O hydrogen bonding results in a three-dimensional network. The Ag
I centre is four-coordinated by three N atoms from three different 2-aminopyrimidine ligands and one O atom from one iminodiacetate ligand. Comparison of the structural features with previous findings suggests that the existence of a second ligand plays an important role in the construction of such polymer frameworks.
Supporting information
CCDC reference: 746045
All reagents and solvents were obtained commercially and used without further
purification. Silver nitrate (170 mg, 1 mmol) and 2-aminopyrimidine (95 mg, 1 mmol) were dissolved in water (5 ml). To this solution was added a methanolic
solution (5 ml) of iminodiacetic acid (133 mg, 1 mmol) with stirring. The
mixture was stirred for about 20 min at room temperature to give a clear
colourless solution. The resulting solution was kept in darkness for 4 d,
after which time well-formed colourless block-shaped crystals of (I) were
obtained. The product is insoluble in water and methanol.
The aromatic and amino H atoms were generated geometrically (C—H = 0.93 Å
and N—H = 0.90 Å) and were allowed to ride on their parent atoms in the
riding-model approximations, with Uiso(H) = 1.2Ueq(C,N). The
positions and Uiso values of the water H atoms were refined, with the
O—H distances restrained to 0.85 (1) Å.
Data collection: CrysAlis CCD (Oxford Diffraction, 2008); cell refinement: CrysAlis RED (Oxford Diffraction, 2008); data reduction: CrysAlis RED (Oxford Diffraction, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2009).
catena-Poly[[[(iminodiacetato-
κO)silver(I)]-µ
3-2-
aminopyrimidine-
κ3N1:
N2:
N3] monohydrate]
top
Crystal data top
[Ag(C4H6NO4)(C4H5N3)]·H2O | F(000) = 704 |
Mr = 353.09 | Dx = 2.061 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 8629 reflections |
a = 13.495 (3) Å | θ = 6.1–54.9° |
b = 6.5202 (13) Å | µ = 1.79 mm−1 |
c = 14.103 (3) Å | T = 298 K |
β = 113.49 (3)° | Block, colourless |
V = 1138.1 (4) Å3 | 0.50 × 0.30 × 0.30 mm |
Z = 4 | |
Data collection top
Oxford Diffraction Gemini S Ultra diffractometer | 2230 independent reflections |
Radiation source: sealed tube | 2013 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.037 |
Detector resolution: 16.1903 pixels mm-1 | θmax = 26.0°, θmin = 3.2° |
ω scans | h = −16→16 |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008) | k = −7→8 |
Tmin = 0.468, Tmax = 0.615 | l = −16→17 |
9403 measured reflections | |
Refinement top
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.025 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.064 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.08 | w = 1/[σ2(Fo2) + (0.0289P)2 + 0.7853P] where P = (Fo2 + 2Fc2)/3 |
2230 reflections | (Δ/σ)max = 0.036 |
171 parameters | Δρmax = 0.84 e Å−3 |
2 restraints | Δρmin = −0.67 e Å−3 |
Crystal data top
[Ag(C4H6NO4)(C4H5N3)]·H2O | V = 1138.1 (4) Å3 |
Mr = 353.09 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 13.495 (3) Å | µ = 1.79 mm−1 |
b = 6.5202 (13) Å | T = 298 K |
c = 14.103 (3) Å | 0.50 × 0.30 × 0.30 mm |
β = 113.49 (3)° | |
Data collection top
Oxford Diffraction Gemini S Ultra diffractometer | 2230 independent reflections |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008) | 2013 reflections with I > 2σ(I) |
Tmin = 0.468, Tmax = 0.615 | Rint = 0.037 |
9403 measured reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.025 | 2 restraints |
wR(F2) = 0.064 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.08 | Δρmax = 0.84 e Å−3 |
2230 reflections | Δρmin = −0.67 e Å−3 |
171 parameters | |
Special details top
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. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
Ag1 | 0.505184 (17) | −0.05560 (3) | 0.363312 (16) | 0.03553 (10) | |
O1 | 0.31897 (15) | 0.0875 (3) | 0.29507 (14) | 0.0330 (4) | |
O2 | 0.30387 (16) | −0.2039 (3) | 0.20966 (15) | 0.0418 (5) | |
O3 | −0.11448 (18) | 0.5458 (3) | 0.11212 (16) | 0.0474 (5) | |
O4 | 0.05387 (17) | 0.5604 (3) | 0.23040 (16) | 0.0452 (5) | |
N1 | 0.55486 (17) | −0.0520 (3) | 0.20288 (15) | 0.0257 (4) | |
H1A | 0.5950 | 0.0601 | 0.2060 | 0.031* | |
H1B | 0.5955 | −0.1629 | 0.2053 | 0.031* | |
N2 | 0.42832 (16) | −0.2350 (3) | 0.06723 (14) | 0.0233 (4) | |
N3 | 0.42247 (16) | 0.1315 (3) | 0.07246 (14) | 0.0231 (4) | |
N4 | 0.11408 (15) | 0.2039 (3) | 0.18785 (15) | 0.0253 (4) | |
H4A | 0.1638 | 0.2995 | 0.1923 | 0.030* | |
H4B | 0.1130 | 0.1914 | 0.2510 | 0.030* | |
C1 | 0.3308 (2) | 0.1276 (4) | −0.01377 (18) | 0.0281 (5) | |
H1 | 0.2975 | 0.2513 | −0.0415 | 0.034* | |
C2 | 0.2844 (2) | −0.0514 (4) | −0.0626 (2) | 0.0313 (6) | |
H2 | 0.2205 | −0.0516 | −0.1216 | 0.038* | |
C3 | 0.3373 (2) | −0.2313 (4) | −0.01952 (18) | 0.0279 (5) | |
H3 | 0.3088 | −0.3549 | −0.0519 | 0.033* | |
C4 | 0.4667 (2) | −0.0517 (3) | 0.11073 (18) | 0.0206 (5) | |
C5 | 0.2670 (2) | −0.0402 (3) | 0.22768 (18) | 0.0253 (5) | |
C6 | 0.1489 (2) | 0.0054 (4) | 0.1599 (2) | 0.0285 (5) | |
H6A | 0.1393 | 0.0093 | 0.0880 | 0.034* | |
H6B | 0.1039 | −0.1038 | 0.1677 | 0.034* | |
C7 | 0.00698 (18) | 0.2783 (4) | 0.11535 (17) | 0.0274 (5) | |
H7A | −0.0478 | 0.1766 | 0.1088 | 0.033* | |
H7B | 0.0077 | 0.3003 | 0.0476 | 0.033* | |
C8 | −0.0195 (2) | 0.4798 (4) | 0.15619 (19) | 0.0294 (5) | |
O1W | −0.2232 (2) | 0.5509 (3) | −0.09963 (17) | 0.0448 (5) | |
H1WA | −0.247 (3) | 0.435 (3) | −0.126 (3) | 0.053 (10)* | |
H1WB | −0.186 (3) | 0.542 (6) | −0.0349 (10) | 0.081 (15)* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Ag1 | 0.03753 (15) | 0.01852 (13) | 0.04244 (15) | 0.00165 (7) | 0.00740 (10) | 0.00067 (7) |
O1 | 0.0281 (10) | 0.0287 (9) | 0.0353 (9) | −0.0030 (7) | 0.0052 (8) | −0.0010 (7) |
O2 | 0.0392 (11) | 0.0334 (10) | 0.0475 (11) | 0.0130 (8) | 0.0118 (9) | −0.0044 (8) |
O3 | 0.0355 (12) | 0.0504 (13) | 0.0447 (12) | 0.0178 (9) | 0.0037 (9) | −0.0051 (9) |
O4 | 0.0390 (12) | 0.0386 (11) | 0.0470 (12) | 0.0057 (8) | 0.0053 (10) | −0.0143 (9) |
N1 | 0.0240 (11) | 0.0164 (10) | 0.0303 (10) | 0.0000 (7) | 0.0042 (9) | 0.0002 (7) |
N2 | 0.0262 (10) | 0.0167 (9) | 0.0260 (9) | −0.0015 (7) | 0.0095 (8) | −0.0005 (8) |
N3 | 0.0261 (10) | 0.0168 (9) | 0.0246 (9) | 0.0010 (8) | 0.0082 (8) | 0.0011 (8) |
N4 | 0.0224 (10) | 0.0220 (10) | 0.0284 (10) | 0.0009 (8) | 0.0069 (8) | −0.0020 (8) |
C1 | 0.0285 (13) | 0.0247 (12) | 0.0286 (12) | 0.0030 (10) | 0.0089 (10) | 0.0052 (10) |
C2 | 0.0289 (14) | 0.0309 (14) | 0.0258 (12) | −0.0019 (10) | 0.0020 (10) | 0.0009 (10) |
C3 | 0.0301 (13) | 0.0250 (12) | 0.0270 (11) | −0.0055 (10) | 0.0098 (10) | −0.0038 (9) |
C4 | 0.0217 (11) | 0.0186 (12) | 0.0234 (11) | −0.0002 (8) | 0.0109 (9) | −0.0003 (8) |
C5 | 0.0253 (13) | 0.0241 (12) | 0.0272 (12) | 0.0009 (9) | 0.0110 (10) | 0.0045 (9) |
C6 | 0.0262 (13) | 0.0217 (11) | 0.0331 (12) | 0.0006 (10) | 0.0072 (10) | −0.0058 (10) |
C7 | 0.0219 (12) | 0.0302 (12) | 0.0254 (11) | 0.0018 (9) | 0.0045 (10) | 0.0001 (10) |
C8 | 0.0291 (14) | 0.0292 (13) | 0.0278 (12) | 0.0052 (10) | 0.0091 (11) | 0.0019 (10) |
O1W | 0.0539 (14) | 0.0394 (12) | 0.0391 (12) | −0.0096 (9) | 0.0167 (11) | −0.0002 (9) |
Geometric parameters (Å, º) top
Ag1—O1 | 2.4868 (19) | C4—N3 | 1.348 (3) |
Ag1—N1 | 2.604 (2) | C4—N1 | 1.368 (3) |
Ag1—N2i | 2.3312 (19) | C3—N2 | 1.345 (3) |
Ag1—N3ii | 2.2872 (19) | C3—C2 | 1.381 (3) |
C1—N3 | 1.345 (3) | C3—H3 | 0.9300 |
C1—C2 | 1.373 (4) | C6—N4 | 1.483 (3) |
C1—H1 | 0.9300 | C6—H6A | 0.9700 |
C8—O4 | 1.235 (3) | C6—H6B | 0.9700 |
C8—O3 | 1.257 (3) | C2—H2 | 0.9300 |
C8—C7 | 1.533 (3) | N1—H1A | 0.9000 |
C5—O2 | 1.246 (3) | N1—H1B | 0.9000 |
C5—O1 | 1.248 (3) | N4—H4A | 0.9000 |
C5—C6 | 1.526 (3) | N4—H4B | 0.9000 |
C7—N4 | 1.480 (3) | N3—Ag1i | 2.2872 (19) |
C7—H7A | 0.9700 | N2—Ag1ii | 2.3312 (19) |
C7—H7B | 0.9700 | O1W—H1WA | 0.844 (10) |
C4—N2 | 1.349 (3) | O1W—H1WB | 0.849 (10) |
| | | |
O1—Ag1—N1 | 103.35 (7) | N4—C6—H6A | 109.3 |
O1—Ag1—N2i | 89.22 (6) | C5—C6—H6A | 109.3 |
O1—Ag1—N3ii | 133.95 (6) | N4—C6—H6B | 109.3 |
N1—Ag1—N2i | 99.65 (6) | C5—C6—H6B | 109.3 |
N1—Ag1—N3ii | 97.77 (6) | H6A—C6—H6B | 108.0 |
N2i—Ag1—N3ii | 126.98 (7) | C1—C2—C3 | 116.7 (2) |
N3—C1—C2 | 122.7 (2) | C1—C2—H2 | 121.7 |
N3—C1—H1 | 118.6 | C3—C2—H2 | 121.7 |
C2—C1—H1 | 118.6 | C4—N1—Ag1 | 113.44 (16) |
O4—C8—O3 | 126.1 (3) | C4—N1—H1A | 108.9 |
O4—C8—C7 | 117.0 (2) | Ag1—N1—H1A | 108.9 |
O3—C8—C7 | 116.9 (2) | C4—N1—H1B | 108.9 |
O2—C5—O1 | 125.4 (2) | Ag1—N1—H1B | 108.9 |
O2—C5—C6 | 116.2 (2) | H1A—N1—H1B | 107.7 |
O1—C5—C6 | 118.5 (2) | C6—N4—C7 | 115.36 (18) |
N4—C7—C8 | 109.34 (18) | C6—N4—H4A | 108.4 |
N4—C7—H7A | 109.8 | C7—N4—H4A | 108.4 |
C8—C7—H7A | 109.8 | C6—N4—H4B | 108.4 |
N4—C7—H7B | 109.8 | C7—N4—H4B | 108.4 |
C8—C7—H7B | 109.8 | H4A—N4—H4B | 107.5 |
H7A—C7—H7B | 108.3 | C1—N3—C4 | 116.5 (2) |
N2—C4—N3 | 125.1 (2) | C1—N3—Ag1i | 117.92 (15) |
N2—C4—N1 | 117.49 (19) | C4—N3—Ag1i | 125.50 (16) |
N3—C4—N1 | 117.41 (19) | C3—N2—C4 | 116.4 (2) |
N2—C3—C2 | 122.7 (2) | C3—N2—Ag1ii | 117.21 (15) |
N2—C3—H3 | 118.7 | C4—N2—Ag1ii | 126.14 (15) |
C2—C3—H3 | 118.7 | H1WA—O1W—H1WB | 111 (4) |
N4—C6—C5 | 111.47 (19) | C5—O1—Ag1 | 102.62 (15) |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+1, y−1/2, −z+1/2. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O2i | 0.90 | 2.09 | 2.904 (3) | 151 |
N1—H1B···O1ii | 0.90 | 2.00 | 2.896 (3) | 178 |
N4—H4A···O1Wiii | 0.90 | 2.03 | 2.781 (3) | 140 |
N4—H4B···O4iv | 0.90 | 2.52 | 3.070 (3) | 120 |
O1W—H1WA···O2v | 0.84 (1) | 1.88 (1) | 2.714 (3) | 168 (4) |
O1W—H1WB···O3 | 0.85 (1) | 1.91 (1) | 2.753 (3) | 174 (5) |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+1, y−1/2, −z+1/2; (iii) −x, −y+1, −z; (iv) −x, y−1/2, −z+1/2; (v) −x, −y, −z. |
Experimental details
Crystal data |
Chemical formula | [Ag(C4H6NO4)(C4H5N3)]·H2O |
Mr | 353.09 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 298 |
a, b, c (Å) | 13.495 (3), 6.5202 (13), 14.103 (3) |
β (°) | 113.49 (3) |
V (Å3) | 1138.1 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 1.79 |
Crystal size (mm) | 0.50 × 0.30 × 0.30 |
|
Data collection |
Diffractometer | Oxford Diffraction Gemini S Ultra diffractometer |
Absorption correction | Multi-scan (CrysAlis RED; Oxford Diffraction, 2008) |
Tmin, Tmax | 0.468, 0.615 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 9403, 2230, 2013 |
Rint | 0.037 |
(sin θ/λ)max (Å−1) | 0.617 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.025, 0.064, 1.08 |
No. of reflections | 2230 |
No. of parameters | 171 |
No. of restraints | 2 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.84, −0.67 |
Selected geometric parameters (Å, º) topAg1—O1 | 2.4868 (19) | Ag1—N2i | 2.3312 (19) |
Ag1—N1 | 2.604 (2) | Ag1—N3ii | 2.2872 (19) |
| | | |
O1—Ag1—N1 | 103.35 (7) | N1—Ag1—N2i | 99.65 (6) |
O1—Ag1—N2i | 89.22 (6) | N1—Ag1—N3ii | 97.77 (6) |
O1—Ag1—N3ii | 133.95 (6) | N2i—Ag1—N3ii | 126.98 (7) |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+1, y−1/2, −z+1/2. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O2i | 0.90 | 2.09 | 2.904 (3) | 151 |
N1—H1B···O1ii | 0.90 | 2.00 | 2.896 (3) | 178 |
N4—H4A···O1Wiii | 0.90 | 2.03 | 2.781 (3) | 140 |
N4—H4B···O4iv | 0.90 | 2.52 | 3.070 (3) | 120 |
O1W—H1WA···O2v | 0.844 (10) | 1.883 (13) | 2.714 (3) | 168 (4) |
O1W—H1WB···O3 | 0.849 (10) | 1.908 (12) | 2.753 (3) | 174 (5) |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+1, y−1/2, −z+1/2; (iii) −x, −y+1, −z; (iv) −x, y−1/2, −z+1/2; (v) −x, −y, −z. |
Pyrimidine and aminopyrimidine derivatives are biologically important compounds as they occur in nature as components of nucleic acids. Some aminopyrimidine derivatives are used as antifolate drugs (Hunt et al., 1980; Baker & Santi, 1965). They are also used in the development of polymeric metal–organic frameworks (MOFs), owing to their demonstrated ability to form very stable hydrogen-bonded chain arrays via their stereochemically associative amino groups and hetero-ring N atoms, and to coordinate to metal centres through various bonding modes (Aoki et al., 1994; Blake et al., 1999). As a soft acid, the AgI ion is a favourable and fashionable building block or connecting node for coordination polymers, not only due to its ready coordination by soft bases such as unsaturated N atoms (Carlucci et al., 1995), but also because closed-shell d10 Ag···Ag interactions can often give rise to intriguing supramolecular motifs (Blake et al., 2000; Melcer et al., 2001). Recently, we have undertaken a series of investigations into the assembly of AgI ions with different aminopyrimidine derivatives (Luo, Huang, Chen et al., 2008; Luo, Huang, Zhang et al., 2008; Luo et al., 2009), with the principal aim of obtaining supramolecular compounds or ordered coordination polymers, and found that in the resulting structures, aminopyrimidine derivatives often adopt mono- and bidentate coordination modes with AgI ions via their pyrimidyl N atoms. However, tridentate coordination by pyrimidyl and amino N atoms is still quite rare (Wang et al., 2006). The introduction of a second ligand such as a dicarboxylic acid dramatically alters the structures and properties of these complexes. Inspired by these results, we employed 2-aminopyrimidine as a tridentate ligand and incorporated iminodiacetic acid into the previously known AgI–2-aminopyrimidine system, and successfully obtained the title compound, (I), a novel one-dimensional ladder coordination polymer.
Single-crystal X-ray diffraction study reveals that compound (I) comprises one AgI centre, one 2-aminopyrimidine ligand, one iminodiacetate anion and one uncoordinated water molecule. As shown in Fig. 1, the four-coordinated AgI atom adopts a strongly distorted tetrahedral geometry (Table 1), which is coordinated by two pyrimidyl N atoms from two independent 2-aminopyrimidine ligands, one amino N atom from another 2-aminopyrimidine ligand and one O atom from an iminodiacetate anion. The widest N3i—Ag1—O1 angle is 133.95 (6)° and the remaining angles are in the range 89.22 (6)–126.98 (7)°. It is noteworthy that the Ag—Namino distance [Ag1—N1 = 2.604 (2) Å] is significantly longer than the Ag···Npyrimidyl distances [Ag1—N3i = 2.2872 (19) and Ag1—N2ii = 2.3312 (19) Å; symmetry codes: (i) 1 - x, y - 1/2, -z+ 1/2; (ii) 1 - x, y + 1/2, -z + 1/2]. This difference may be partly due to electronic effects between the amino N and pyrimidyl N atoms. A pair of lone electrons on the amino N atom is partially delocalized into the pyrimidyl ring, which makes the amino N atom less basic than the pyrimidyl N atoms. Interestingly, aminopyrimidine derivatives often adopt N-monodentate and N,N'-bidentate coordination modes with AgI via their pyrimidyl N atoms, and the only example adopting tridentate coordination was reported by Wang et al. (2006).
As shown in Fig. 2, the 2-aminopyrimidine ligands of (I) are coordinated to the AgI centres in this N,N',N''-coordination mode to form a one-dimensional ladder structure, in which the iminodiacetate anion adopts a bis-monodentate coordination mode to AgI, precluding the extension of the motif into two dimensions. It is noteworthy that the N atoms of the iminodiacetate anions are protonated, and so do not participate in coordination to any metal centre. All the carboxylate groups are deprotonated, fulfilling the requirement for overall charge neutrality.
In each one-dimensional ladder, AgI ions and 2-aminopyrimidine ligands are interlinked to form chair-like eight-membered M2L2 binuclear rings. Two kinds of intermolecular hydrogen bonds are observed in neighbouring ladders. N—H···O hydrogen bonds have N···O distances in the range 2.781 (3)–3.070 (3) Å. The N atoms of the amino group of the 2-aminopyrimidine ligands and protonated imino groups serve as donors, while the O atoms of the iminodiacetate anion and uncoordinated water molecule act as acceptors. O1W—H···O hydrogen bonds involve the O atoms of the iminodiacetate anion and uncoordinated water molecule, acting as acceptors and donors, respectively. These hydrogen bonds link the ladders into a three-dimensional framework, as shown in Fig. 3.
In conclusion, a new one-dimensional AgI coordination polymer with mixed N-donor and O-donor ligands shows rare N,N',N''-tridentate and O-monodentate coordination modes, respectively.