Guanidine Electron Donors and Silver Halides
N 23.65. 1H NMR (400 MHz, CD3CN): δ = 2.88 (48 H, CH3), 5.16
(2 H, ArH) ppm. 13C NMR (100 MHz, CD3CN): δ = 41.48 (CH3),
be directed into the desired channel. The results of this
work are of special importance for the use of guanidine
electron donors as building blocks in coordination poly-
mers. In these polymers, the guanidine units are generally
highly oxidized and coloured, thus making them attractive
for optical and/or electronic applications. This article shows
how halide clusters of different sizes could be incorporated
into the chain polymers, thereby opening an access route to
well-defined arrays of photoactive silver halide clusters. As
103.90, 157.75, 168.07 ppm. IR (CsI): ν = 2946, 1608, 1583, 1564,
˜
1505, 1468, 1420, 1390, 1301, 1253, 1227, 1190, 1164, 1142, 1057,
1016, 898, 879, 838, 749, 683, 620, 538 cm–1. UV/Vis (CH3CN, c =
6.2ϫ10–5 molL–1): λ (ε in Lmol–1 cm–1) = 218 (59431), 293 (16179),
426 (27073), 589 (614) nm. MS-ESI+: m/z (%) = 265.3 (100) [1]2+
,
530.3 (7) [1]+, 611.0 (7) [1 + Br]+. Crystal data for (1)Br2·4MeOH:
C30H66Br2N12O4, Mr = 818.76, 0.30ϫ0.20ϫ0.20 mm3, mono-
clinic, space group P21/n, a = 9.4670(19) Å, b = 15.321(3) Å, c =
shown for the pairs of compounds [1(Ag6I8)·2DMF]n and 14.612(3) Å, β = 104.29(3), V = 2053.8(7) Å3, Z = 2, dcalcd.
=
1.324 Mgm–3, Mo-Kα radiation (graphite-monochromated, λ =
0.71073 Å), T = 100 K, θrange 2.33 to 32.05°. Reflections measd.
14235, indep. 7130, Rint = 0.0366. Final R indices [IϾ2σ(I)]: R1 =
0.0374, wR2 = 0.0803.
[1(Ag6I8)]n as well as [1(Ag4Cl6)·4CHCl3]n and [1(Ag4Cl6)·
2CH2Cl2]n, the incorporation of solvent molecules leads to
significant changes in the polymer structures.
Compound [1(Ag6I8)]n: AgI (221 mg, 0.942 mmol) was added to a
solution of 1 (100 mg, 0.188 mmol) in MeOH (12 mL). The solu-
tion was stirred for a period of 16 h at room temp., during which
time the formation of brown-red solid was observed. Then the reac-
tion mixture was filtered and the product dried under vacuum;
yield 212 mg (0.097 mmol, 51%). Crystals suitable for XRD were
grown from concentrated DMF solutions. Compound [1(Ag6I8)]·
2DMF: C32H64Ag6I8N14O2 (2339.39): calcd. C 16.43, H 2.76, N
8.38; found C 16.78, H 2.60, N 8.22. 1H NMR (400 MHz,
[D6]DMF): δ = 3.01 (48 H, CH3), 5.35 (2 H, ArH) ppm. Low solu-
Experimental Section
General: The synthetic work was carried out under an inert-gas
atmosphere by using standard Schlenk techniques. All solvents
were dried rigorously prior to their use. UV/Vis spectra were re-
corded with a Varian Cary 5000 spectrometer. NMR spectra were
measured with a Bruker Avance II 400 NMR machine. Elemental
analyses were carried out at the Microanalytical Laboratory of the
University of Heidelberg. IR spectra were recorded with a Biorad
Excalibur FTS3000 spectrometer. Thermogravimetric (TG) and
calorimetric (DSC) measurements were carried out with a Mettler
TC15 and DSC30 apparatus under a N2 atmosphere in a tempera-
ture range of 30–600 °C. The heating rate was varied between 2
and 10 °Cmin–1.
bility hampered the 13C NMR spectra. IR (CsI): ν = 2921, 1677,
˜
1661, 1609, 1577, 1561, 1508, 1492, 1460, 1400, 1384, 1320, 1263,
1231, 1167, 1090, 1022, 897, 813, 785, 737, 701 cm–1. UV/Vis
(CH3CN, c = 7.9ϫ10–6 molL–1): λ (ε in Lmol–1 cm–1) = 245 (6827),
285 (1827), 426 (2431) nm. MS-FAB+: m/z (%) = 531.7 (20) [1 +
H]+, 746.5 (1) [1 + 2Ag]+, 784 (2) [1 + 2I]+, 871.0 (7) [1 +
2Ag+I]+, 891.8 (5) [1 + Ag + 2I]+, 978.6 (3) [1 + 3Ag+I]+, 1063.3
Compound (1)Cl2: AgCl (135 mg, 0.934 mmol) was added to a solu-
tion of 1 (100 mg, 0.188 mmol) in CH3OH (10 mL). The solution
was stirred at room temp. for a period of 2 h, during which time
the solution quickly adopted a deep green colour. After filtration,
4/5 of the solvent volume was removed, and the initial amount of
solvent was restored by the addition of Et2O. A dark crystalline
powder of (1)Cl2 precipitated; yield 80 mg (0.133 mmol, 70%). Sin-
gle crystals suitable for XRD were obtained from CH3CN/Et2O.
C28H58Cl2N12O2 [M + 2MeOH] (665.75): calcd. C 50.51, H 8.78,
N 25.25; found C 49.73, H 8.71, N 25.85. 1H NMR (400 MHz,
CD2Cl2): δ = 2.76 (48 H, CH3), 5.44 (2 H, ArH) ppm. 13C NMR
(100 MHz, CD2Cl2): δ = 40.2 (CH3), 111.6, 135.5, 162.7 ppm. IR
(1) [1
+ 5Ag –
H]+. Crystal data for [1(Ag6I8)]·2DMF:
C16H32Ag3I4N7O, Mr = 1169.70, 0.10ϫ0.10ϫ0.10 mm3, mono-
clinic, space group P21/n, a = 11.727(2) Å, b = 19.456(4) Å, c =
12.991(3) Å, β = 94.21(3)°, V = 2956.0(10) Å3, Z = 4, dcalcd.
=
2.628 Mgm–3, Mo-Kα radiation (graphite-monochromated, λ =
0.71073 Å), T = 100 K, θrange 2.09 to 30.02°. Reflections measd.
16815, indep. 8624, Rint = 0.0600. Final R indices [IϾ2σ(I)]: R1 =
0.0442, wR2 = 0.0781. Crystal data for [1(Ag6I8)]: C13H25Ag3I4N6,
Mr = 1096.6, 0.15ϫ0.10ϫ0.10 mm3, monoclinic, space group C2/
c, a = 13.795(3) Å, b = 14.615(3) Å, c = 25.803(5) Å, β = 104.82(3)°,
V = 5029.2(19) Å3, Z = 8, dcalcd. = 2.897 Mgm–3, Mo-Kα radiation
(graphite-monochromated, λ = 0.71073 Å), T = 100 K, θrange 2.36
to 28.03°. Reflections measd. 24142, indep. 5969, Rint = 0.0516.
Final R indices [IϾ2σ(I)]: R1 = 0.0397, wR2 = 0.0972.
(CsI): ν = 2947, 1608, 1564, 1508, 1467, 1421, 1395, 1304, 1256,
˜
1226, 1187, 1165, 1139, 1057, 1018, 896, 840, 806, 749, 688, 623,
532, 458 cm–1. UV/Vis (CH3CN, c = 3.4ϫ10–5 molL–1): λ (ε in
Lmol–1 cm–1) = 218 (42148), 293 (16240), 425 (24148) nm. MS-
ESI+ (MeOH): m/z (%) = 265.3 (100) [1]2+, 530.3 (56) [1]+, 565.6
(25) [1 + Cl]+. Crystal data for (1)Cl2, C26H50Cl2N12: Mr = 601.68,
0.30ϫ0.11ϫ0.05 mm3, orthorhombic, space group Pca2(1), a =
19.210(4) Å, b = 7.5353(15) Å, c = 21.463(4) Å, V = 3106.8(11) Å3,
Z = 4, dcalcd. = 1.286 Mgm–3, Mo-Kα radiation (graphite-mono-
chromated, λ = 0.71073 Å), T = 100 K, θrange 1.90 to 30.58°. Reflec-
tions measd. 75068, indep. 9521, Rint = 0.0644. Final R indices
[IϾ2σ(I)]: R1 = 0.0430, wR2 = 0.0985.
Compound [1(AgBr)2]n: Compound 1 (500 mg, 0.942 mmol) was
dissolved in CH3CN (10 mL). Subsequently, AgBr (354 mg,
1.884 mmol) was added, and the reaction mixture was heated at
90 °C to reflux for a period of 4 h. Then half of the solvent was
removed under vacuum from the reaction mixture. The reaction
mixture was filtered and washed with a small portion of CH3CN.
The pale yellow product was dried under vacuum to yield 779 mg
(0.860 mmol, 91%) [1(AgBr)2]n. Crystals suitable for an XRD
analysis were obtained from concentrated CH3CN solutions.
C26H50Ag2Br2N12 (906.30): calcd. C 34.46, H 5.56, N 18.55; found
C 34.31, H 5.56, N 18.36. 1H NMR (199.92 MHz, CDCl3): δ =
2.79 (s, 48 H, CH3), 5.38 (s, 2 H, ArH) ppm. 13C NMR
(100.55 MHz, CDCl3): δ = 39.94 (CH3), 110.92, 134.94, 162.10
Compound (1)Br2: AgBr (142 mg, 0.755 mmol) was added to a solu-
tion of 1 (80 mg, 0.151 mmol) in MeOH (10 mL). The solution was
stirred at room temp. for a period of 2 h, during which time the
solution quickly turned deep green. Then the solution was filtered
and the solvent was partially removed to around 2 mL. A dark,
crystalline solid precipitated after the addition of Et2O (restoring
the initial 10 mL volume); yield 71 mg (0.103 mmol, 68%). Crystals
suitable for XRD were grown from MeOH/Et2O. C26H50Br2N12
(690.56): calcd. C 45.22, H 7.30, N 24.34; found C 44.79, H 7.29,
ppm. IR (CsI): ν = 2929 (m), 1515 (s, C=N) , 1382 (s), 1265 (m),
˜
1180 (s), 1063 (m), 1020 (vs), 948 (w), 925 (w), 890 (vs), 867 (s),
776 (m), 712 (m), 573 (m), 426 (w) cm–1. MS-FAB+: m/z (%) =
486.1 (34) [1 – NMe2]+, 531.2 (100) [1 + H]+, 611.2 (2) [1 + Br]+,
Eur. J. Inorg. Chem. 2012, 695–704
© 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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