Benzyl Azide Complexes of Iridium(III)
programs. The iNMR software package12 was used to treat NMR
data. The conductivities of 10-3 mol dm-3 solutions of the com-
plexes in CH3NO2 at 25 °C were measured with a Radiometer CDM
83.
Synthesis of Complexes. Hydride complex IrHCl2(PiPr3)2 was
prepared by following the reported method.13
Chart 1
IrHCl2(PiPr3)P2 (1) [P ) P(OEt)3 (a), PPh(OEt)2 (b)]. An
excess of the appropriate phosphite (1.10 mmol) was added to a
solution of IrHCl2(PiPr3)2 (0.15 g, 0.26 mmol) in 10 mL of benzene,
and the reaction mixture was refluxed for 1 h. The solvent was
removed under reduced pressure to give an oil which was triturated
with ethanol (2 mL). Cooling the resulting solution to -25 °C
yielded yellow crystals, which slowly separated out and were then
filtered and crystallized from ethanol; yield g70%.
on iridium, which allowed the isolation and full characteriza-
tion of the first η1-organic azide complexes for this metal,
are reported here.
Anal. Calcd for C21H52Cl2IrO6P3 (1a): C, 33.33; H, 6.93; Cl,
9.37. Found: C, 33.19; H, 7.05; Cl, 9.18. 1H NMR (CD2Cl2,
20 °C) (δ): 4.15 (m, 12 H, CH2), 2.73 (m, 1 H, CH), 1.34, 1.29 (d,
6 H, CH3 iPr), 1.30, 1.25 (t, 18 H, CH3 OEt), ABCX spin syst, δX
-12.10, JAX ) 255.0, JBX ) 19.7, JCX ) 10.8 Hz (1 H, IrH). 31P-
{1H} NMR (CD2Cl2, 20 °C) (δ): ABC spin syst, δA 85.2, δB 77.0,
δC 0.57, JAB ) 27.6, JAC ) 27.3, JBC ) 547.6 Hz. IR (KBr): νIrH
Experimental Section
General Comments. All synthetic work was carried out in an
inert atmosphere (Ar) using standard Schlenk techniques or a
vacuum atmosphere drybox. Once isolated, the complexes were
found to be relatively stable in air but were stored in an inert
atmosphere at -25 °C. All solvents were dried over appropriate
drying agents, degassed on a vacuum line, and distilled into vacuum-
tight storage flasks. IrCl3‚3H2O was a Pressure Chemical Co.
product, used as received. Phosphine PPh(OEt)2 was prepared by
the method of Rabinowitz and Pellon,9 while P(OEt)3 was an
Aldrich product purified by distillation under nitrogen. Alkyl10 and
aryl11 azides were prepared following methods previously reported.
The labeled C6H5CH215N3 azide was prepared by following the same
method,10 by reacting Na[15NNN] (98% enriched, CIL) with benzyl
bromide, C6H5CH2Br. Equimolar mixtures of C6H5CH215NNN and
C6H5CH2NN15N were obtained. Other reagents were purchased from
commercial sources in the highest available purity and used as
received. Infrared spectra were recorded on a Perkin-Elmer
Spectrum One spectrophotometer. NMR spectra (1H, 31P, 13C, 15N)
were obtained on AC200 or Avance 300 Bruker spectrometers at
temperatures between -90 and +30 °C, unless otherwise noted.
1H and 13C spectra are referred to internal tetramethylsilane; 31P-
{1H} chemical shifts are reported with respect to 85% H3PO4, while
15N shifts are with respect to CH315NO2, in both cases with
downfield shifts considered positive. The COSY, HMQC, and
HMBC NMR experiments were performed using their standard
2081 (m), νIrCl 320 (m) cm-1
.
Anal. Calcd for C29H52Cl2IrO4P3 (1b): C, 42.44; H, 6.39; Cl,
8.64. Found: C, 42.69; H, 6.26; Cl, 8.49. 1H NMR (CD2Cl2,
20 °C) (δ): 7.92-7.31 (m, 10 H, Ph), 4.10, 3.89, 3.69 (m, 8 H,
CH2), 2.64 (m, 1 H, CH), 1.30, 1.27 (d, 6 H, CH3 iPr), 1.25, 1.23
(t, 12 H, CH3 OEt), ABCX spin syst, δX -12.41, JAX ) 221.4, JBX
) 467.3, JCX ) 11.1 Hz (1 H, IrH). 31P{1H} NMR (CD2Cl2,
20 °C) (δ): ABC spin syst, δA 102.7, δB 98.0, δC 2.51, JAB
17.7, JAC ) 23.0, JBC ) 467.3 Hz. IR (KBr): νIrH 2126 (m), νIrCl
322 (m) cm-1
)
.
IrHCl2P3 (2) [P ) P(OEt)3 (a), PPh(OEt)2 (b)]. An excess of
the appropriate phosphite (2.20 mmol) was added to a solution of
IrHCl2(PiPr3)2 (0.30 g, 0.52 mmol) in 20 mL of toluene, and the
reaction mixture was refluxed for 4 h. The solvent was removed
under reduced pressure to give an oil which was triturated with
ethanol (4 mL). Cooling the resulting solution to -25 °C yielded
yellow crystals, which slowly separated out in 1-2 days and were
then collected and dried under vacuum; yield g70%.
Anal. Calcd for C18H46Cl2IrO9P3 (2a): C, 28.35; H, 6.08; Cl,
9.30. Found: C, 28.17; H, 6.15; Cl, 9.11. 1H NMR (CD2Cl2,
20 °C) (δ): 4.15 (m, 18 H, CH2), 1.24, 1.21 (t, 27 H, CH3), AB2X
spin syst, δX -11.67, JAX ) 366, JBX ) 24 Hz (1 H, IrH). 31P{1H}
NMR (CD2Cl2, 20 °C) (δ): AB2 spin syst, δA 84.8, δB 76.0, JAB
)
53.0 Hz. IR (KBr): νIrH 2051 (m), νIrCl 318 (m) cm-1
.
(7) (a) Albertin, G.; Antoniutti, S.; Bacchi, A.; Bordignon, E.; Busatto,
F.; Pelizzi, G. Inorg. Chem. 1997, 36, 1296-1305. (b) Albertin, G.;
Antoniutti, S.; Bacchi, A.; Bergamo, M.; Bordignon, E.; Pelizzi, G.
Inorg. Chem. 1998, 37, 479-489. (c) Albertin, G.; Antoniutti, S.;
Bacchi, A.; Barbera, D.; Bordignon, E.; Pelizzi, G.; Ugo, P. Inorg.
Chem. 1998, 37, 5602-5610. (d) Albertin, G.; Antoniutti, S.;
Bordignon, E.; Menegazzo, F. J. Chem. Soc., Dalton Trans. 2000,
1181-1189. (e) Albertin, G.; Antoniutti, S.; Bacchi, A.; Ballico, G.
B.; Bordignon, E.; Pelizzi, G.; Ranieri, M.; Ugo, P. Inorg. Chem. 2000,
39, 3265-3279. (f) Albertin, G.; Antoniutti, S.; Bacchi, A.; Bordignon,
E.; Miani, F.; Pelizzi, G. Inorg. Chem. 2000, 39, 3283-3293. (g)
Albertin, G.; Antoniutti, S.; Bortoluzzi, M.; Castro-Fojo, J.; Garcia-
Fonta´n, S. Inorg. Chem. 2004, 43, 4511-4522. (h) Albertin, G.;
Antoniutti, S.; Bedin, M.; Castro, J.; Garc´ıa-Fonta´n, S. Inorg. Chem.
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Anal. Calcd for C30H46Cl2IrO6P3 (2b): C, 41.96; H, 5.40; Cl,
8.26. Found: C, 42.09; H, 5.28; Cl, 8.34. 1H NMR (CD2Cl2,
20 °C) (δ): 7.70, 7.36 (m, 15 H, Ph), 4.08, 3.90, 3.70 (m, 12 H,
CH2), 1.26, 1.22 (t, 18 H, CH3), AB2X spin syst, δX -11.78, JAX
) 318, JBX ) 24 Hz (1 H, IrH). 31P{1H} NMR (CD2Cl2, 20 °C)
(δ): AB2 spin syst, δA 102.9, δB 97.9, JAB ) 34.0 Hz. IR (KBr):
νIrH 2062 (m), νIrCl 323 (m) cm-1
.
[IrCl2(η1-N3CH2Ar)P3]BPh4 (3, 4) [Ar ) C6H5 (3), 4-CH3C6H4
(4); P ) P(OEt)3 (a), PPh(OEt)2 (b)]. An equimolar amount of
HBF4‚Et2O (0.12 mmol, 17 µL of a 54% solution in diethyl ether)
was added to a solution of hydride IrHCl2P3 (0.12 mmol) in 8 mL
of dichloromethane cooled to -196 °C. The reaction mixture was
left to reach room temperature and stirred for 1 h, and then an
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T.; Pelizzi, G. Angew. Chem., Int. Ed. 2002, 41, 2192-2194. (b)
Albertin, G.; Antoniutti, S.; Bacchi, A.; De Marchi, F.; Pelizzi, G.
Inorg. Chem. 2005, 44, 8947-8954. (c) Albertin, G.; Antoniutti, S.;
Bordignon, E.; Carrera, B. Inorg. Chem. 2000, 39, 4646-4650. (d)
Albertin, G.; Antoniutti, S.; Bacchi, A.; Boato, M.; Pelizzi, G. J. Chem.
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S.; Giorgi, M. T. Eur. J. Inorg. Chem. 2003, 2855-2866.
(10) Alvarez, S. G.; Alvarez, M. T. Synthesis 1997, 413-414.
(11) Lindsay, R. O.; Allen, C. F. H. Org. Synth. 1955, 3, 710-711.
(13) Simpson, R. D.; Marshall, W. J.; Farischon, A. A.; Roe, D. C.; Grushin,
V. V. Inorg. Chem. 1999, 38, 4171-4173.
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Inorganic Chemistry, Vol. 47, No. 2, 2008 743