Au-Ln Arrays with 5-Ethynyl-2,2′-Bipyridine
(bpyC≡CAu)2(µ-dppp) (2). This compound was prepared by the
same synthetic procedure as that of 1 except for using dppp instead of
dppe. Yield: 68%. Anal. Calcd for C51H40Au2N4P2: C, 52.59; H, 3.46;
N, 4.81. Found: C, 52.27; H, 3.62; N, 4.90. ESI-MS (m/z): 1165 [M
CAu)2(µ-dppb) (3) with stirring for 1 h. After filtered, the concentrated
dichloromethane solutions were layered with n-hexane to afford the
desired products as pale yellow crystals in 55-70% yields.
7 (Ln ) Nd). Yield: 62%. Anal. Calcd. for C164H96Au4Nd4-
F72N8O24P4: C, 36.35; H, 1.79; N, 2.07. Found: C, 36.59; H, 1.90;
N, 2.26. IR spectrum (KBr, cm-1): 2121m (C≡C), 1654s (CdO).
8 (Ln ) Eu). Yield: 55%. Anal. Calcd. for C164H96Au4Eu4-
F72N8O24P4: C, 36.14; H, 1.78; N, 2.06. Found: C, 36.05; H, 1.81;
N, 2.16. spectrum (KBr, cm-1): 2121m (C≡C), 1654s (CdO).
9 (Ln ) Er). Yield: 68%. Anal. Calcd. for C164H96Au4Er4-
F72N8O24P4: C, 35.74; H, 1.76; N, 2.03. Found: C, 35.65; H, 1.81;
N, 2.03. IR spectrum (KBr, cm-1): 2122m (C≡C), 1652s (CdO).
10 (Ln ) Yb). Yield: 70%. Anal. Calcd. for C164H96Au4F72-
N8O24P4Yb4: C, 35.59; H, 1.75; N, 2.02. Found: C, 35.55; H, 1.80;
N, 2.08. IR spectrum (KBr, cm-1): 2122m (C≡C), 1653s (CdO).
1
+ H]+, 985 [M-bpyC≡C]+. H NMR (CDCl3, ppm): 8.80 (s, 2H,
bpyC≡C), 8.67 (d, 2H, J ) 3.5 Hz, bpyC≡C), 8.39 (d, 2H, J ) 7.5
Hz, bpyC≡C), 8.33 (d, 2H, J ) 8.5 Hz, bpyC≡C), 7.89 (d, 2H, J )
7.5 Hz, bpyC≡C), 7.80 (t, 2H, J ) 7.0 Hz, bpyC≡C), 7.45-7.72 (m,
20H, C6H5), 7.30 (d, 2H, J ) 7.0 Hz, bpyC≡C), 2.86 (m, 4H, CH2),
1.83 (m, 2H, CH2). 31P NMR (CDCl3, ppm): 34.9. IR spectrum (KBr,
cm-1): 2111m (C≡C).
(bpyC≡CAu)2(µ-dppb) (3). This compound was prepared by
the same synthetic procedure as that of 1 except for using dppb
instead of dppe. Yield: 68%. Anal. Calcd for C52H42Au2N4P2 ·
CH2Cl2: C, 50.37; H, 3.51; N, 4.43. Found: C, 49.92; H, 3.68; N,
4.16. ESI-MS (m/z): 1179 [M + H]+, 999 [M-bpyC≡C]+. 1H NMR
(CDCl3, ppm): 8.81 (s, 2H, bpyC≡C), 8.67 (d, 2H, J ) 3.5 Hz,
bpyC≡C), 8.38 (d, 2H, J ) 7.5 Hz, bpyC≡C), 8.32 (d, 2H, J )
8.0 Hz, bpyC≡C), 7.91 (d, 2H, J ) 8.5 Hz, bpyC≡C), 7.80 (t, 2H,
J ) 8.0 Hz, bpyC≡C), 7.48-7.69 (m, 20H, C6H5), 7.30 (d, 2H, J
) 5.0 Hz, bpyC≡C), 2.43 (m, 4H, CH2), 1.81 (m, 4H, CH2). 31P
NMR (CDCl3, ppm): 37.6. IR spectrum (KBr, cm-1): 2114m
(C≡C).
{(µ-dppf)(AuC≡Cbpy)2}{Ln(hfac)3}2 (Ln ) Nd, Eu, Er,
and Yb). These compounds were prepared by the similar synthetic
procedures as those of {(AuC≡Cbpy)2(µ-dppb)}2{Ln(hfac)3}4
(7-10) except for using 6 instead of 3. Yields: 65-80%.
11 (Ln ) Nd). Yield: 61%. Anal. Calcd. for C88H52Au2Nd2F36-
FeN4O14P2: C, 36.82; H, 1.83; N, 1.95. Found: C, 36.93; H, 1.79;
N, 1.96. IR spectrum (KBr, cm-1): 2121m (C≡C), 1654s (CdO).
12 (Ln ) Eu).Yield: 76%. Anal. Calcd. for C88H52Au2Eu2F36-
FeN4O14P2: C, 36.54; H, 1.81; N, 1.94. Found: C, 36.43; H, 1.85;
N, 1.88. IR spectrum (KBr, cm-1): 2121m (C≡C), 1654s (CdO).
13 (Ln ) Er). Yield: 80%. Anal. Calcd. for C88H52Au2Er2F36-
FeN4O14P2: C, 36.21; H, 1.80; N, 1.92. Found: C, 36.45; H, 1.73;
N, 1.92. IR spectrum (KBr, cm-1): 2113m (C≡C), 1657s (CdO).
14 (Ln ) Yb).Yield: 65%. Anal. Calcd. for C88H52Au2F36FeN4-
O14P2Yb2: C, 36.06; H, 1.79; N, 1.91. Found: C, 36.15; H, 1.80;
N, 1.92. IR spectrum (KBr, cm-1): 2122m (C≡C), 1653s (CdO).
Physical Measurements. Elemental analyses (C, H, N) were
carried out on a Perkin-Elmer model 240C elemental analyzer.
Electrospray ion mass spectroscopy (ESI-MS) was performed on a
Finnigan LCQ mass spectrometer using dichloromethane-methanol
mixture as mobile phases. 1H and 31P NMR spectra were measured
on a Varian UNITY-500 spectrometer with SiMe4 as the internal
reference and 85% H3PO4 as external standard, respectively.
UV-vis absorption spectra were measured on a Perkin-Elmer
Lambda 25 UV-vis spectrophotometer. Infrared (IR) spectra were
recorded on a Magna750 FT-IR spectrophotometer with KBr pellet.
Emission and excitation spectra in the UV-vis region were recorded
on a Perkin-Elmer LS 55 luminescence spectrometer with a red-
sensitive photomultiplier type R928. Emission lifetimes in solid
states and degassed solutions were determined on an Edinburgh
Analytical Instrument (F900 fluorescence spectrometer) using LED
laser at 397 nm excitation and the resulting emission was detected
by a thermoelectrically cooled Hamamatsu R3809 photomultiplier
tube. The instrument response function at the excitation wavelength
was deconvolved from the luminescence decay. Near-infrared (NIR)
emission spectra were measured on an Edinburgh FLS920 fluo-
rescence spectrometer equipped with a Hamamatsu R5509-72
supercooled photomultiplier tube at 193 K and a TM300 emission
monochromator with NIR grating blazed at 1000 nm. The NIR
emission spectra were corrected via a calibration curve supplied
with the instrument. The emission quantum yields (Φ) of 1-5 in
degassed dichloromethane solutions at room temperature were
calculated by Φs ) Φr(Br/Bs)(ns/nr)2(Ds/Dr) using Cy3PAuC≡CPh
in dichloromethane as the standard (Φem ) 0.08),22 whereas 8 and
(bpyC≡CAu)2(µ-dpppen) (4). This compound was prepared by
the same synthetic procedure as that of 1 except for using dpppen
instead of dppe. Yield: 62%. Anal. Calcd for C53H44Au2N4-
P2 ·CH3OH: C, 53.37; H, 3.72; N, 4.70. Found: C, 52.95; H, 4.06;
1
N, 4.52. ESI-MS (m/z): 1013 [M-bpyC≡C]+. H NMR (CDCl3,
ppm): 8.80 (s, 2H, bpyC≡C), 8.67 (d, 2H, J ) 3.5 Hz, bpyC≡C),
8.38 (d, 2H, J ) 7.5 Hz, bpyC≡C), 8.31 (d, 2H, J ) 8.0 Hz,
bpyC≡C), 7.88 (d, 2H, J ) 8.0 Hz, bpyC≡C), 7.80 (t, 2H, J ) 7.5
Hz, bpyC≡C), 7.47-7.71 (m, 20H, C6H5), 7.29 (d, 2H, J ) 4.0
Hz, bpyC≡C), 2.40 (m, 8H, CH2), 1.81 (m, 2H, CH2). 31P NMR
(CDCl3, ppm): 37.1. IR spectrum (KBr, cm-1): 2112m (C≡C).
(bpyC≡CAu)2(µ-dpph) (5). This compound was prepared by
the same synthetic procedure as that of 1 except for using dpph
instead of dppe. Yield: 58%. Anal. Calcd for C54H46Au2N4P2: C,
53.74; H, 3.84; N, 4.64. Found: C, 53.77; H, 3.99; N, 4.70. ESI-
MS (m/z): 1207 [M + H]+, 1027 [M-bpyC≡C]+. 1H NMR (CDCl3,
ppm): 8.79 (s, 2H, bpyC≡C), 8.67 (d, 2H, J ) 4.0 Hz, bpyC≡C),
8.38 (d, 2H, J ) 8.0 Hz, bpyC≡C), 8.31 (d, 2H, J ) 8.5 Hz,
bpyC≡C), 7.89 (d, 2H, J ) 8.0 Hz, bpyC≡C), 7.80 (t, 2H, J ) 7.5
Hz, bpyC≡C), 7.46-7.70 (m, 20H, C6H5), 7.29 (d, 2H, J ) 7.5
Hz, bpyC≡C), 2.40 (m, 8H, J ) 7.5 Hz, CH2), 1.46 (m, 4H, CH2).
31P NMR (CDCl3, ppm): 37.8. IR spectrum (KBr, cm-1): 2097m
(C≡C).
(bpyC≡CAu)2(µ-dppf) (6). This compound was prepared by
the same synthetic procedure as that of 1 except for using dppf
instead of dppe. Yield: 70%. Anal. Calcd for C58H42Au2N4FeP2:
C, 53.31; H, 3.24; N, 4.29. Found: C, 53.15; H, 3.46; N, 4.23. ESI-
MS (m/z): 1306 [M]+, 1127 [M - bpyC≡C]+, 751 [M-Au(bpy-
C≡C)2]+. 1H NMR (CDCl3, ppm): 8.82 (s, 2H, bpyC≡C), 8.67 (d,
2H, J ) 3.5 Hz, bpyC≡C), 8.39 (d, 2H, J ) 8.0 Hz, bpyC≡C),
8.32 (d, 2H, J ) 8.5 Hz, bpyC≡C), 7.91 (d, 2H, J ) 8.0 Hz,
bpyC≡C), 7.81 (t, 2H, J ) 8.0 Hz, bpyC≡C), 7.43-7.57 (m, 20H,
C6H5), 7.30 (d, 2H, J ) 5.0 Hz, bpyC≡C), 4.76 (s, 4H, C5H4),
4.34 (s, 4H, C5H4). 31P NMR (CDCl3, ppm): 36.8. IR spectrum
(KBr, cm-1): 2111m (C≡C).
12 using [Ru(bpy)3](PF6)2 in acetonitrile as the standard (Φem
)
0.062).26 The subscripts r and s denote reference standard and the
sample solution, respectively; and n, D and Φ are the refractive
index of the solvents, the integrated intensity and the luminescence
{(AuC≡Cbpy)2(µ-dppb)}2{Ln(hfac)3}4 (Ln ) Nd, Eu, Er,
and Yb). The Au4Ln4 compounds were prepared by addition of 2.2
equiv of Ln(hfac)3(H2O)2 to a dichloromethane solution of (bpyC≡
Inorganic Chemistry, Vol. 47, No. 22, 2008 10751