Synthesis of luminescent gold(I) and gold(III) complexes with a triphosphine ligand

Article abstract of DOI:10.1021/ic000802v

We have synthesized and characterized a series of trinuclear gold(I) complexes [(AuX)₃(μ-triphos)] (triphos = bis(2-diphenylphosphinoethyl)phenylphosphine; X = Cl 1, Br 2, I 3, C₆F₅ 4) and di- and trinuclear gold(III) comp

Full text of DOI:10.1021/ic000802v

Inorg. Chem. 2001, 40, 2675-2681
2675
Synthesis of Luminescent Gold(I) and Gold(III) Complexes with a Triphosphine Ligand
Manuel Bardaj´ı, Antonio Laguna,*,† and Javier Vicente
Departamento de Qu´ımica Inorga´nica, Instituto de Ciencia de Materiales de Arago´n,
Universidad de Zaragoza-CSIC, E-50009 Zaragoza, Spain
Peter G. Jones
Institut fu¨r Anorganische und Analytische Chemie der Technischen Universita¨t,
Postfach 3329, D-38023 Braunschweig, Germany
ReceiVed July 18, 2000
We have synthesized and characterized a series of trinuclear gold(I) complexes [(AuX)3(µ-triphos)] (triphos )
bis(2-diphenylphosphinoethyl)phenylphosphine; X ) Cl 1, Br 2, I 3, C6F5 4) and di- and trinuclear gold(III)
complexes [{Au(C6F5)3}n(µ-triphos)] (n ) 2 (5), 3 (6)). The crystal structure of 6 [{Au(C6F5)3}3(µ-triphos)] has
been determined by X-ray diffraction studies, which show the triphosphine in a conformation resulting in very
long gold-gold distances, probably associated with the steric requirements of the tris(pentafluorophenyl)gold-
(III) units. Complex 6 crystallizes in the triclinic space group P(-1) with a ) 12.7746(16) Å, b ) 18.560(2) Å,
c ) 21.750(3) Å, R ) 98.215(3)°, â ) 101.666(3)°, γ ) 96.640(3)°, and Z ) 2. Chloride substitutions in complex
1 afford trinuclear gold(I) complexes [(AuX)3(µ-triphos)] (X ) Fmes (1,3,5-tris(trifluoromethyl)phenyl) 7, p-SC6H4-
Me 8, SCN 9) and [Au3Cl3-n(S2CNR2)n(µ-triphos)] (R ) Me, n ) 3 (10), 2 (12), 1 (14); R ) CH2Ph, n ) 3 (11),
2 (13), 1 (15)). The luminescence properties of these complexes in the solid state have been studied; at low
temperature most of them are luminescent, including the gold(III) derivative 6, with the intensity and the emission
maxima being clearly influenced by the nature and the number of the ligands bonded to the gold centers.
Introduction
In contrast to the extensive studies of the photochemical and
photophysical properties of gold(I) complexes, few investiga-
A large number of polydentate phosphine complexes of
transition metals have been synthesized and characterized that
have potential catalytic and biomedical activity. Additionally,
they promote short metal-metal distances, which can lead to
interesting electrochemical and optical properties.1-10
Photoluminescence studies have shown that a variety of
mono- and polynuclear phosphine-gold(I) or phosphine-
thiolate-gold(I) derivatives display luminescence in the visible
region. The emissions have been generally assigned as a
phosphorescence arising from metal-centered transitions or
sulfur to gold charge transfer modified by the presence of gold-
gold contacts.11-14
tions of this type have been conducted on related gold(III)
complexes; luminescent gold(III) complexes are rare and only
some cyclometalated, diimine or dithiolate derivatives have been
reported.15-19
In this paper we report the synthesis and optical properties
of a series of triphosphine di- or trinuclear gold(I) or gold(III)
derivatives containing different kind of ligands such as halide,
fluorophenyl, thiolate, thiocyanate, and dithiocarbamate.
Experimental Section
General. All the reactions were carried out under an argon
atmosphere at room temperature. IR spectra were recorded on a Perkin-
Elmer 883 spectrophotometer, over the range 4000-200 cm-1, using
† Tel.: + 34 976 761185. Fax: + 34 976 761187. e-mail: alaguna@
posta.unizar.es.
(1) Pignolet, L. H. Homogeneous Catalysis with Metal Phosphine
Complexes; Plenum Press: New York, 1983.
(2) Sacconi, L.; Mani, F. Transition Met. Chem. 1982, 8, 179.
(3) Sung, K. M.; Huh, S.; Jun, M. J. Polyhedron 1999, 18, 469.
(4) Hong, B.; Woodcock, S. R.; Saito, S. K.; Ortega, J. V. Dalton Trans.
1998, 2615.
1
1
Nujol mulls between polyethylene sheets. H, H{31P}, 19F, and 31P-
{1H} NMR spectra were recorded on a Bruker ARX‚300 or GEMINI
2000 apparatus in CDCl3 solutions (if no other solvent is stated);
chemical shifts are quoted relative to SiMe4 (external, 1H), CFCl3
(external, 19F), and 85% H3PO4 (external, 31P). C, H, N, and S analyses
(5) Cotton, F. A.; Hong B. Inorg. Chem. 1993, 32, 2354.
(6) Mayer, H. A.; Kaska, W. C. Chem. ReV. 1994, 94, 1239.
(7) Sevillano, P.; Habtemariam, A.; Parsons, S.; Castin˜eiras, A.; Garc´ıa,
M. E.; Sadler, P. J. Dalton Trans. 1999, 2861.
(8) Bianchini, C.; Meli, A.; Moneti, S.; Vizza, F. Organometallics 1998,
17, 2636.
(13) Tang, S. S.; Chang, C.; Lin, I. J. B.; Liou, L.; Wang, J. Inorg. Chem.
1997, 36, 2294.
(14) Yam, V. W.-W.; Lo K. K.-W. Chem. Soc. ReV. 1999, 28, 323 and
references therein.
(15) Liu, H.-Q.; Cheung, T.-C.; Peng, S.-M.; Che, C. M. J. Chem. Soc.,
Chem. Commun. 1995, 1787.
(9) Docket, D. W., Panwick, P. E.; Kubiak, C. P. J. Am. Chem. Soc. 1996,
118, 4846.
(10) Baker, P. K.; Meehan, M. M. J. Organomet. Chem. 1999, 582, 259.
(11) Forward, J. M.; Bohmann, D.; Fackler, J. P., Jr.; Staples, R. J. Inorg.
Chem. 1995, 34, 6330.
(12) Jones, W. B.; Yuan, J.; Narayanaswamy, R.; Young, M. A.; Elder, R.
C.; Bruce, A. E.; Bruce M. R. M. Inorg. Chem. 1995, 34, 1996.
(16) Wong, K.-H.; Cheung, K.-K.; Chan, M. C.-W.; Che, C. M. Organo-
metallics 1998, 17, 3505.
(17) Yam, V. W. W.; Choi, S. W.-K.; Lai, T. F.; Lee, W.-K J. Chem. Soc.,
Dalton Trans. 1993, 1001.
(18) Chan, C.-W.; Wong, W.-T.; Che, C. M. Inorg. Chem. 1994, 33, 1266.
(19) Mansour, M. A.; Lachicotte, R. J.; Gysling, H. J.; Eisenberg, R. Inorg.
Chem. 1998, 37, 4625.
10.1021/ic000802v CCC: $20.00 © 2001 American Chemical Society
Published on Web 05/01/2001

2676 Inorganic Chemistry, Vol. 40, No. 12, 2001
Bardaj´ı et al.
were performed with a Perkin-Elmer 2400 microanalyzer. Conductivi-
ties were measured in acetone solution with a Philips PW 9509
apparatus. Mass spectra were recorded on a VG Autospec using the
LSIMS technique (with Cs gun) and 3-nitrobenzyl alcohol as matrix.
UV-vis absorption spectra in dichloromethane solution were recorded
at 298 K on a Unicam UV/Vis 2. The luminescence spectra were
recorded on a Perkin-Elmer LS-50B spectrofluorometer.
(m, 8Fm), -161.3 to -161.6 (m, 6Fm). 31P{1H} NMR: δ 16.7 (m, 2P),
14.5 (m, 1P). Anal. Calcd for C88H33Au3F45P3: C, 40.2; H, 1.25.
Found: C, 40.15; H, 1.45. LSIMS (m/z, %, assignment): 1763 (25,
[M - Au - 4C6F5]+), 731 (100, [Au(triphos)]+).
[{Au(Fmes)}3(µ-triphos)] 7. To a freshly prepared diethyl ether
solution of [Li(Fmes)]24 (Fmes ) 1,3,5-tris(trifluoromethyl)phenyl; 0.6
mmol) was added complex 1 (0.123 g, 0.1 mmol). After 20 h of stirring,
two drops of water were added to hydrolyze the excess lithium reagent.
The mixture was dried and filtered through a sodium sulfate sinter.
The clear solution was evaporated to dryness. The white residue was
washed with pentane (2 × 5 mL). Yield of 7: 55%. Λ: 7.6 ohm-1
Preparation of Compounds. [(AuX)3(µ-triphos)] X ) Cl 1, Br 2,
I 3, C6F5 4. To a 10 mL dichloromethane solution of [AuX(tht)]20,21
(tht ) tetrahydrothiophene; 0.3 mmol; X ) Cl, 0.096 g; C6F5 0.136 g)
or [AuX(AsPh3)]22 (0.3 mmol; X ) Br, 0.175 g; I 0.189 g) was added
bis(2-diphenylphosphinoethyl)phenylphosphine (triphos; 0.053 g, 0.1
mmol). After 2 h of stirring, the solution was concentrated to ca. 3
mL. Addition of diethyl ether (1-2) or petroleum ether (3-4) afforded
complexes 1-4 as white solids, which were washed with more diethyl
ether or petroleum ether (2 × 5 mL). Yield of 1: 95%. Λ: 2.1 ohm-1
cm2 mol-1. 1H NMR: δ 7.7-7.4 (m, 25H, Ph), 2.75 (m, 2H, P-CH2),
2.31 (m, 6H, P-CH2). 31P{1H} NMR: δ 34.0, 31.8, AB2 spin system
1
cm2 mol-1. H NMR: δ 8.2-7.4 (m, 31H, Ph and Fmes), 2.85 (m,
2H, P-CH2), 2.55 (m, 2H, P-CH2), 2.34 (m, 4H, P-CH2); 19F NMR:
δ -60.19 (s, 6Fo), -60.55 (s, 12Fo), -63.54 (s, 3Fp), -63.56 (s, 6Fp).
3
31P{1H} NMR: δ 43.1, 41.4, A2B spin system with JAB ) 56.2 Hz.
Anal. Calcd for C61H39Au3F27P3: C, 37.2; H, 2.0. Found: C, 37.45; H,
2.35. LSIMS (m/z, %, assignment): 1688 (5, [M - (Fmes)]+), 1210
(75, [Au2(Fmes)(triphos)]+).
3
[{Au(p-SC6H4Me)}3(µ-triphos)] 8. To a 10 mL dichloromethane
solution of complex 1 (0.123 g, 0.1 mmol) was added a freshly prepared
methanol solution (10 mL) of [Na(SC6H4Me)] (prepared from NaOMe
and p-HSC6H4Me; 0.3 mmol). After 2 h of stirring, the mixture was
evaporated to dryness. Dichloromethane was added to the residue, which
was then filtered and concentrated. The white product 8 was precipitated
by addition of pentane and washed with pentane (2 × 5 mL). Yield of
with JAB ) 54.7 Hz. Anal. Calcd for C34H33Au3Cl3P3: C, 33.15; H,
2.7. Found: C, 32.8; H, 2.65. LSIMS (m/z, %, assignment): 1195 (100,
[M - Cl]+), 963 (40, [Au2Cl(triphos)]+). Yield of 2: 80%. Λ: 3.4
1
ohm-1 cm2 mol-1. H NMR: δ 7.7-7.4 (m, 25H, Ph), 2.81 (m, 2H,
P-CH2), 2.37 (m, 6H, P-CH2). 31P{1H} NMR: δ 35.2, 33.3, AB2
spin system with 3JAB ) 52.0 Hz. Anal. Calcd for C34H33Au3Br3P3: C,
29.9; H, 2.4. Found: C, 30.35; H, 2.9. LSIMS (m/z, %, assignment):
1285 (100, [M - Br]+), 1007 (49, [Au2Br(triphos)]+). Yield of 3: 77%.
1
8: 60%. Λ: 27.6 ohm-1 cm2 mol-1. H NMR: δ 7.8-7.4 (m, 37H,
1
Λ: 3.5 ohm-1 cm2 mol-1. H NMR: δ 7.8-7.4 (m, 25H, Ph), 2.88
Ph), 2.77 (m, 2H, P-CH2), 2.47 (m, 6H, P-CH2), 2.26 (s, 9H, Me).
31P{1H} NMR: δ 37.3 (m, 1P), 35.3 (m, 2P). 31P{1H} NMR (-60
°C): δ 37.3 (m, 1P), 35.3 (m, 2P). Anal. Calcd for C55H54Au3P3S3: C,
44.2; H, 3.6; S, 6.45. Found: C, 44.4; H, 3.35; S, 6.1. LSIMS (m/z, %,
assignment): 1371 (100, [M - SC6H4Me]+), 1051 (74, [Au2(SC6H4-
Me)(triphos)]+).
(m, 2H, P-CH2), 2.41 (m, 6H, P-CH2); 31P{1H} NMR: δ 36.5, 35.7,
AB2 spin system with 3JAB ) 50.5 Hz. Anal. Calcd for C34H33Au3I3P3:
C, 27.1; H, 2.2. Found: C, 27.4; H, 2.5. LSIMS (m/z, %, assignment):
1378 (100, [M - I]+), 1055 (30, [Au2I(triphos)]+). Yield of 4: 75%.
1
Λ: 3.8 ohm-1 cm2 mol-1. H NMR: δ 7.8-7.4 (m, 25H, Ph), 2.8-
2.4 (m, 8H, P-CH2). 19F NMR: δ -117.34 (m, 4Fo), -117.60 (m, 2Fo),
-159.28 (t, 2Fp), -159.35 (t, 1Fp), -163.2 to -163.5 (m, 6Fm). 31P-
{1H} NMR: δ 39.6. 31P{1H} NMR (CD2Cl2, -90 °C): δ 35.9 (br,
2P), 34.9 (br, 1P). Anal. Calcd for C52H33Au3F15P3: C, 38.4; H, 2.05.
Found: C, 38.6; H, 2.25. LSIMS (m/z, %, assignment): 1459 (65, [M
- C6F5]+), 1095 (100, [Au2(C6F5)(triphos)]+).
[{Au(SCN)}3(µ-triphos)] 9. To a dichloromethane solution (10 mL)
of of complex 1 (0.123 g, 0.1 mmol) was added an aqueous (5 mL)
solution of KSCN (0.029 g, 0.3 mmol). The solid dissolved rapidly,
and the resulting clear solution was stirred for about 2 h. Then the
organic layer was extracted, dried with anhydrous Na2SO4 ,and filtered.
Concentration to ca. 2 mL and addition of diethyl ether (10 mL)
afforded complex 9 as a white solid, which was washed with diethyl
[{Au(C6F5)3}2(µ-triphos)] 5. To a dichloromethane solution (10 mL)
of [Au(C6F5)3(tht)]23 (0.157 g, 0.2 mmol) was added triphos (0.053 g,
0.1 mmol). The solution was stirred for 2 h. Then, it was concentrated
to ca. 2 mL. Addition of cold hexane (10 mL) afforded 5 as a white
solid. A second fraction was obtained by concentration and cooling to
-18 °C. Complex 5 was washed with hexane (2 × 5 mL). Yield of 5:
1
ether (2 × 5 mL). Yield of 9: 60%. Λ: 30.5 ohm-1 cm2 mol-1. H
NMR: δ 7.8-7.5 (m, 25H, Ph), 2.80 (m, 2H, P-CH2), 2.50 (m, 6H,
P-CH2). 31P{1H} NMR: δ 33.9 (s). 31P{1H} NMR (-60 °C): δ 34.0
(s). 31P{1H} NMR (CD2Cl2): δ 33.8 (s). 31P{1H} NMR (CD2Cl2, -90
°C): δ 30.7 (s). Anal. Calcd for C55H54Au3P3S3: C, 34.2; H, 2.55; N,
3.25; S, 7.4. Found: C, 33.8; H, 2.65, N, 3.2; S, 7.05. LSIMS (m/z, %,
assignment): 1241 (100, [M - SCN]+), 986 (58, [Au2(SCN)-
(triphos)]+).
1
68%. Λ: 13.2 ohm-1 cm2 mol-1. H NMR: δ 7.6-6.9 (m, 25H, Ph),
2.5-2.0 (m, 8H, P-CH2). 19F NMR: δ -120.9 (m, 4Fo), -121.5 (m,
16Fo), -122.0 (m, 4Fo), -122.7 (m, 8Fo), -123.0 (m, 4Fo), -155.6 (t,
4Fp), -156.3 (t, 4Fp), -156.7 (t, 1Fp), -157.3 (t, 4Fp), -157.6 (t, 1Fp),
-157.7 (t, 1Fp), -158.1 (t, 2Fp), -158.4 (t, 1Fp), -160.2 to -160.6
(m, 16Fm), -161.2 (m, 8Fm), -161.8 to -162.2 (m, 12Fm). 31P{1H}
[Au3Cl3-n(S2CNMe2)n(µ-triphos)]; n ) 3 (10), 2 (12), 1 (14). To
a dichloromethane solution (20 mL) of 1 (0.123 g, 0.1 mmol) was added
NaS2CNMe2 (0.3 mmol, 43 mg; 0.2 mmol, 29 mg; 0.1 mmol, 14 mg).
The solid dissolved rapidly, and the resulting yellow solution was stirred
for about 2 h and then filtered through Celite and concentrated to ca.
2 mL. Addition of diethyl ether (20 mL) afforded complexes 10, 12,
or 14 as yellow solids, which were washed with diethyl ether (2 × 5
mL). Yield of 10: 75%. Λ: 15.3 ohm-1 cm2 mol-1. 1H NMR: δ 7.8-
7.3 (m, 25H, Ph), 3.49 (s, 18H, Me), 2.80 (m, 2H, P-CH2), 2.40 (m,
6H, P-CH2). 31P{1H} NMR: δ 36.6 (m, 1P), 34.8 (m, 2P). 31P{1H}
3
3
NMR: δ 16.3 (m, 6P), -11.4 (d, JPP ) 35.2 Hz, 1P), -11.7 (d, JPP
) 29.2 Hz, 1P), -15.4 (t, 3JPP ) 34.2 Hz, 1P). Anal. Calcd for C70H33-
Au2F30P3: C, 43.55; H, 1.7. Found: C, 43.5; H, 2.0. LSIMS (m/z, %,
assignment): 1763 (10, [M - C6F5]+), 731 (100, [Au(triphos)]+).
[{Au(C6F5)3}3(µ-triphos)] 6. To a dichloromethane solution (10 mL)
of [Au(C6F5)3(tht)] (0.236 g, 0.3 mmol) was added triphos (0.053 g,
0.1 mmol). The solution was stirred for 2 h and then concentrated to
ca. 2 mL. Addition of cold hexane (10 mL) afforded 6 as a white solid.
A second fraction was obtained by concentration and cooling to -18
°C. Complex 6 was washed with hexane (2 × 5 mL). Yield of 6: 65%.
3
NMR (-60 °C): δ 37.0, 34.7 (s), AB2 spin system with JAB ) 56.6
Hz. Anal. Calcd for C43H51Au3N3P3S6: C, 34.75; H, 3.45; N, 2.85; S,
12.95. Found: C, 34.4; H, 3.65, N, 2.7; S, 12.65. LSIMS (m/z, %,
assignment): 1366 (31, [M - S2CNMe2]+), 1049 (34, [Au2(S2CNMe2)-
(triphos)]+), 731 (100, [Au(triphos)]+). Yield of 12: 70%. Λ: 88.9
1
Λ: 19.3 ohm-1 cm2 mol-1. H NMR: δ 7.9-6.8 (m, 25H, Ph), 2.02
(m, 8H, P-CH2). 19F NMR: δ -121.5 (m, 4Fo), -122.0 (m, 8Fo),
-123.1 (m, 4Fo), -123.8 (m, 2Fo), -153.1 (t, 2Fp), -156.0 (t, 4Fp),
-156.5 (t, 1Fp), -157.3 (t, 2Fp), -159.2 (m, 4Fm), -160.2 to -160.5
1
ohm-1 cm2 mol-1. H NMR: δ 8.1-7.3 (m, 25H, Ph), 3.52 (s, 12H,
Me), 3.20-2.50 (m, 8H, P-CH2). 31P{1H} NMR: δ 32.5 (br). 31P-
{1H} NMR (-60 °C): δ 31.0 (s, 2P), 30.2 (s, 1P). 31P{1H} NMR (CD2-
Cl2, -90 °C): δ 31.0 (s, 2P), 28.7 (s, 1P). Anal. Calcd for
C40H45Au3ClN2P3S4: C, 34.25; H, 3.25; N, 2.0; S, 9.15. Found: C,
33.9; H, 3.15, N, 2.0; S, 8.95. LSIMS (m/z, %, assignment): 1366
(20) Uso´n, R.; Laguna, A.; Laguna, M. Inorg. Synth. 1989, 26, 85.
(21) Uso´n, R.; Laguna, A.; Vicente, J. J. Chem. Soc., Chem. Commun.
1976, 353.
(22) McAuliff, C. A.; Parish, R. V.; Randal, P. D. Dalton Trans. 1979,
1730.
(23) Uso´n, R.; Laguna, A.; Laguna, M. Inorg. Synth. 1989, 26, 87.
(24) Carr, G. E.; Chambers, R. D.; Holmes; T. F.; Parker, D. G. J.
Organomet. Chem. 1987, 325, 13.

Synthesis of Luminescent Au(I) and Au(III) Complexes
Inorganic Chemistry, Vol. 40, No. 12, 2001 2677
Table 1. Crystallograhic Data for Complex 6
Scheme 1
chem formula
fw
temp
cryst syst
space group
unit cell dimens
C88H41Au3Cl3F45P3
2743.37
-130(2) °C
triclinic
P(-1)
a ) 12.7746(16) Å
b ) 18.560(2) Å
c ) 21.750(3) Å
4942.5(10) Å3
2
R ) 98.215(3)°
â ) 101.666(3)°
γ ) 96.640(3)°
volume
Z
density (obsd)
density (calcd)
abs coeff
not measured
1.843 Mg/m3
4.699 mm-1
final R indices [I > 2σ(I)] R1a ) 0.0532,
wR2b) 0.1336
R1 ) 0.0898,
wR2 ) 0.1539
R indices (all data)
largest diff. peak and hole 3.202 and -3.080 e Å-3
[R(int) ) 0.0550] were used for all calculations; θ range for data
collection from 1.35 to 30.03°; index ranges -17 e h e 17, -26 e k
e 26, -30 e l e 30; completeness to θ ) 30.00° was 98.8%. An
absorption correction was based on multiple scans (program SADABS);
transmission factors are in the range 0.573-0.962. The structure was
refined anisotropically on F2 (program SHELXL-9725) using a system
of restraints (to light atom U values and local ring symmetry). H atoms
were included using a riding model. Two ill-defined regions of residual
electron density were tentatively interpreted as partially occupied
solvent. Goodness-of-fit on F2 is 1.031.
2
a R1(F)) Σ||Fo| - |Fc||/Σ|Fo|. b wR2(F2) ) [Σ{w(Fo - Fc2)2}/Σ
{w(Fo )2}]0.5; w-1 ) σ2(Fo ) + (aP)2 + bP, where P ) [Fo2 + 2Fc2]/3
2
2
and a and b are constants adjusted by the program.
(52, [M - Cl]+), 1281 (7, [M - S2CNMe2]+), 1048 (33, [Au2(S2-
CNMe2)(triphos)]+), 731 (100, [Au(triphos)]+). Yield of 14: 72%. Λ:
61.5 ohm-1 cm2 mol-1. H NMR: δ 8.3-7.5 (m, 25H, Ph), 3.65 (s,
1
6H, Me), 3.42 (br, 2H, P-CH2), 3.10 (br, 2H, P-CH2), 2.60 (br, 4H,
P-CH2). 31P{1H} NMR: δ 29.8 (br); 31P{1H} NMR (-60 °C): δ 28.5
(s), 27.8 (s), 26.0 (s). Anal. Calcd for C37H39Au3Cl2NP3S2: C, 33.75;
H, 3.0; N, 1.05; S, 4.9. Found: C, 33.55; H, 3.1, N, 1.1; S, 4.9. LSIMS
(m/z, %, assignment): 1281 (100, [M - Cl]+), 1196 (7, [M -
S2CNMe2]+), 1049 (16, [Au2(S2CNMe2)(triphos)]+), 731 (15, [Au-
(triphos)]+).
Results and Discussion
Synthesis and Characterization. The reaction of bis(2-
diphenylphosphinoethyl)phenylphosphine (triphos) with the
appropriate gold(I) complex [AuXL] (X ) Cl, Br, I, C6F5; L )
tetrahydrothiophene (tht), AsPh3) containing an easily displace-
able ligand in molar ratio 1:3 in dichloromethane leads to the
trinuclear gold(I) complexes 1-4 (see Scheme 1). These
derivatives are air-and moisture-stable white solids at room
temperature. Their IR spectra show absorptions at 326 (1) cm-1
due to ν(Au-Cl)26 or at 954 and 792 cm-1 from the pentafluo-
rophenyl groups27 (4). Their acetone solutions are nonconduct-
[Au3Cl3-n(S2CN(CH2Ph)2)n(µ-triphos)]; n ) 3 (11), 2 (13), 1 (15).
To a dichloromethane solution (20 mL) of 1 (0.123 g, 0.1 mmol) was
added a 3 mL aqueous solution of NaS2CN(CH2Ph)2 (0.3 mmol, 89
mg; 0.2 mmol, 59 mg; 0.1 mmol, 29 mg). The solid dissolved rapidly,
and the resulting yellow solution was stirred for about 2 h. Then the
organic layer was extracted, dried with anhydrous Na2SO4, and filtered.
Concentration to ca. 2 mL and addition of diethyl ether (15 mL)
afforded complexes 11, 13, or 15 as yellow solids, which were washed
with diethyl ether (2 × 5 mL). Yield of 11: 68%. Λ: 19.8 ohm-1 cm2
1
ing. The H NMR spectra show the triphosphine protons, the
mol-1. H NMR: δ 8.0-7.2 (m, 55H, Ph), 5.14 (s, 12H, N-CH2),
1
CH2CH2 bridges being observed as two signals for 1-3 (integral
2:6) and a complicated multiplet for 4. The 19F NMR spectrum
of 4 shows the pattern of two different pentafluorophenyl groups
in a 2:1 ratio. The 31P{1H} NMR spectra of complexes 1-3
show an AB2 spin system in which δPPh is always the lowest
2.90 (m, 2H, P-CH2), 2.40 (m, 6H, P-CH2). 31P{1H} NMR: δ 36.4,
34.8, AB2 spin system with 3JAB ) 56.1 Hz. 31P{1H} NMR (-60 °C):
3
δ 36.3, 34.6, AB2 spin system with JAB ) 56.3 Hz. Anal. Calcd for
C79H75Au3N3P3S6: C, 48.85; H, 3.9; N, 2.15; S, 9.9. Found: C, 48.75;
H, 3.9, N, 2.0; S, 9.7. LSIMS (m/z, %, assignment): 1669 (41, [M -
S2CN(CH2Ph)2]+), 1200 (26, [Au2(S2CN(CH2Ph)2)(triphos)]+), 731
field resonance varying from 34.0 to 36.5 ppm while δ
lies
PPh2
in the range 31.8-35.7 ppm; both signals are low-field shifted
on going from Cl to Br to I, as found in [(AuX)2(µ-dppm)]
(dppm ) bis(diphenylphosphine)methane) but in the opposite
order to that in [(AuX)2(µ-tppm)] (tppm ) tris(diphenylphos-
phine)methane).28 The 31P{1H} NMR spectrum of 4 shows only
a singlet at 39.6 ppm, which only at 183 K changes to two
broad and close resonances at 35.9 and 34.9 ppm in a 2:1 ratio;
this can be interpreted as two isochronous phosphorus centers
with a slightly different chemical shift on varying the temper-
ature. The LSIMS mass spectra show the peak corresponding
to [M - X]+ at m/z (% abundance, X) ) 1195 (100, Cl), 1285
(100, Br), 1378 (100, I) and 1459 (65, C6F5), respectively, for
1-4.
(100, [Au(triphos)]+). Yield of 13: 72%. Λ: 21.8 ohm-1 cm2 mol-1
.
1H NMR: δ 8.2-7.2 (m, 45H, Ph), 5.10 (s, 8H, N-CH2), 3.40-2.50
(m, 8H, P-CH2); 31P{1H} NMR: δ 31.9 (s, 2P), 30.0 (s, 1P). 31P{1H}
NMR (-60 °C): δ 31.2 (s, 2P), 29.5 (s, 1P). Anal. Calcd for C64H61-
Au3ClN2P3S4: C, 45.05; H, 3.6; N, 1.65; S, 7.5. Found: C, 44.75; H,
3.5, N, 1.55; S, 7.1. LSIMS (m/z, %, assignment): 1669 (19, [M -
Cl]+), 1200 (20, [Au2(S2CN(CH2Ph)2)(triphos)]+), 731 (100, [Au-
(triphos)]+). Yield of 15: 75%. Λ: 18.4 ohm-1 cm2 mol-1. 1H NMR:
δ 8.3-7.5 (m, 35H, Ph), 5.20 (s, 4H, N-CH2), 3.35 (br, 2H, P-CH2),
2.95 (br, 2H, P-CH2), 2.60 (br, 4H, P-CH2). 31P{1H} NMR: δ 30.1
(br). 31P{1H} NMR (-60 °C): δ 30.4 (s), 27.2 (s), 25.0 (s). Anal. Calcd
for C49H47Au3Cl2NP3S2: C, 40.05; H, 3.2; N, 0.95; S, 4.35. Found: C,
40.2; H, 3.55, N, 1.1; S, 4.6. LSIMS (m/z, %, assignment): 1432 (93,
[M - Cl]+), 1196 (60, [M - S2CN(CH2Ph)2]+), 731 (100, [Au-
(triphos)]+).
Crystal Structure Determination of 6. Some crystallographic data
of [{Au(C6F5)3}3(µ-triphos)] are given in Table 1. Colorless crystals
of 6 were grown from dichloromethane and chloroform/petroleum ether.
A tablet ca. 0.4 mm × 0.2 mm × 0.1 mm was mounted in an inert oil
on a glass fiber. A total of 58818 reflections were collected on a Bruker
SMART 1000 CCD diffractometer at -130 °C, using monochromated
Mo KR radiation (λ ) 0.710 73 Å); 28562 independent reflections
(25) Sheldrick, G. M. SHELXL 97: A Program for Crystal Structure
Refinement, University of Go¨ttingen: Go¨ttingen, Germany, 1997.
(26) Uso´n, R.; Laguna, A.; Laguna, M.; Fraile, M. N.; Jones, P. G.;
Sheldrick, G. M. J. Chem. Soc., Dalton Trans. 1986, 291.
(27) Uso´n, R.; Laguna, A.; Garc´ıa, J.; Laguna, M. Inorg. Chim. Acta 1979,
37, 201.
(28) Xiao, H.; Weng, Y.; Wong, W.; Mak, T. C. W.; Che, C. Dalton Trans.
1997, 221.

2678 Inorganic Chemistry, Vol. 40, No. 12, 2001
Bardaj´ı et al.
Scheme 2
Table 2. 31P{1H} NMR Data for Complexes 7-15 in CDCl3
Solutiona
We have also synthesized gold(III) derivatives containing this
triphosphine ligand by reaction of triphos with [Au(C6F5)3(tht)]
in a 1:2 or 1:3 molar ratio, which affords the dinuclear 5 or
trinuclear complex 6. Complex 5 reacts with [Au(C6F5)3(tht)]
to give complex 6. Complexes 5-6 are air- and moisture-stable,
white solids at room temperature. Their acetone solutions are
nonconducting. In the IR spectra, absorptions at ca. 970 and
795 cm-1 from the pentafluorophenyl groups are observed. The
19F NMR spectrum of 6 shows two different tris(pentafluo-
rophenyl)gold(III) units, while the spectrum of 5 is much more
complex. The 31P{1H} NMR spectrum of 6 shows two reso-
nances centered at 16.7 and 14.5 ppm in a 2:1 ratio, which are
observed as multiplets because of P-P and P-F couplings. The
31P{1H} NMR spectrum of 5 is more complex and shows four
resonances, one multiplet due to gold-coordinated phosphine
at 16.3 ppm, two doublets from uncoordinated phosphine
centered at -11.4 and -11.7 ppm, and a triplet at -15.4 ppm.
Therefore, complex 5 must be a mixture of three isomers, which
can be postulated as one containing uncoordinated PPh2 and
the other uncoordinated PPh (the chemical shifts are close to
those found for PPh2 and PPh in the free phosphine); the isomer
with uncoordinated PPh2 could be in two different conformations
to give two doublets. The LSIMS mass spectra of 5-6 show a
peak at m/z (%) ) 1763 (10, [M - C6F5]+, 5; 25 [M - Au-
4C6F5]+, 6) and the base peaks at 731 due to [Au(triphos)]+.
δ (18 °C)
δ (-55 °C)
complex
P1, P2, P3
P1, P2, P3
7
8
9
43.1, 41.4, 43.1
35.3, 37.3, 35.3
33.9b
35.3, 37.3, 35.3
34.0,b 30.7b,c
10
11
12
34.8, 36.6, 34.8
34.8, 36.4, 34.8
32.5b
34.7, 37.0, 34.7
34.6, 36.3, 34.6
31.0, 30.2, 31.0
31.0, 28.7, 31.0c
31.2, 29.5, 31.2
28.5,b 27.8,b 26.0b
30.4,b 27.2,b 25.0b
13
14
15
31.9, 30.0, 31.9
29.8b
30.1b
a P1, P2, and P3 assigned as follows: P1 and P3 are the lateral
phosphorus whereas P2 is the central one. Coupling constants and spin
system are given in the Experimental Section. b Broad signal that is
not possible to assign to P1, P2, P3. c Measured in CD2Cl2 at -90 °C.
14 (with chloride and methyl dithiocarbamate) which means
that for the latter there is some chloride dissociation in the
solution.
The 31P{1H} NMR spectrum of 7 show an A2B spin system
with ∆δAB ) 1.7 ppm (see Table 2 for chemical shifts) while
in the 19F NMR spectrum two kinds of o-CF3 (in the ratio 6:12)
and p-CF3 (in the ratio 3:6) are observed, as expected for two
different Fmes ligands, one trans to PPh and two trans to PPh2.
The 31P{1H} NMR spectrum of 8 is an ill-defined AB2 spin
system even at low temperature. In contrast, complex 9 displays
only the resonance already described for 4, which shows a
shoulder at -55 °C but at - 90 °C becomes a singlet. This can
again be interpreted as two isochronous phosphorus. Complex
10 shows an ill-defined AB2 spin system in the 31P{1H} NMR
spectrum which becomes well-defined at low temperature while
for the analogous complex 11 an AB2 spin system is found at
both temperatures. In the 31P{1H} NMR spectrum of 12, only
one resonance is observed, which at -55 °C or at -90 °C splits
into two singlet resonances, while for the similar complex 13
there are two singlet resonances at room and low temperature;
several structures are possible and fluxional processes occur at
least in the case of the methyl dithiocarbamate, which can
involve the two dithiocarbamate ligands and the chloride.
Finally, the 31P{1H} NMR spectra of 14-15 consist of a broad
The starting material that allows us to introduce other ligands
is the trinuclear chloro-gold(I) derivative 1, by means of chloro
substitution reactions (see Scheme 2). Treatment of 1 [(AuCl)3-
(µ-triphos)] with a freshly prepared ether solution of Li(Fmes)
(Fmes ) 1,3,5-tris(trifluoromethyl)phenyl) leads to the orga-
nometallic complex 7 as a white solid. The same procedure but
using a freshly prepared methanol solution of sodium p-
methylphenylthiolate or an aqueous solution of potassium
thiocyanate affords complexes 8 and 9. The reaction of 1 with
sodium dithiocarbamate in a 1:1, 1:2, or 1:3 molar ratio affords
complexes 10-15 as yellow solids.
These derivatives are air- and moisture-stable solids at room
temperature. The IR spectrum of 8 shows absorptions at 2117
and 2079 cm-1 from thiocyanate. Acetone solutions are
nonconducting, although show some conductivity for 12 and

Synthesis of Luminescent Au(I) and Au(III) Complexes
Inorganic Chemistry, Vol. 40, No. 12, 2001 2679
Table 3. Selected Bond Lengths [Å] and Angles [deg]
Au(1)-C(31)
Au(1)-C(21)
Au(1)-C(11)
Au(1)-P(1)
Au(2)-C(81)
Au(2)-C(91)
Au(2)-C(71)
Au(2)-P(2)
Au(3)-C(131)
Au(3)-C(141)
Au(3)-C(121)
Au(3)-P(3)
2.054(7)
2.063(7)
2.079(7)
2.3564(17)
2.057(7)
2.073(7)
2.079(7)
2.3454(16)
2.047(7)
2.075(7)
2.078(7)
2.3434(17)
P(1)-C(41)
P(1)-C(51)
P(1)-C(1)
P(2)-C(61)
P(2)-C(2)
P(2)-C(3)
P(3)-C(101)
P(3)-C(111)
P(3)-C(4)
C(1)-C(2)
C(3)-C(4)
1.799(6)
1.807(7)
1.828(6)
1.794(7)
1.810(6)
1.820(6)
1.797(7)
1.815(7)
1.832(6)
1.529(9)
1.523(9)
C(31)-Au(1)-C(21)
C(31)-Au(1)-C(11)
C(21)-Au(1)-C(11)
C(31)-Au(1)-P(1)
C(21)-Au(1)-P(1)
C(11)-Au(1)-P(1)
C(81)-Au(2)-C(91)
C(81)-Au(2)-C(71)
C(91)-Au(2)-C(71)
C(81)-Au(2)-P(2)
C(91)-Au(2)-P(2)
C(71)-Au(2)-P(2)
C(131)-Au(3)-C(141) 87.8(3)
C(131)-Au(3)-C(121) 88.2(3)
C(141)-Au(3)-C(121) 173.5(2)
C(131)-Au(3)-P(3)
C(141)-Au(3)-P(3)
C(121)-Au(3)-P(3)
C(41)-P(1)-C(51)
C(41)-P(1)-C(1)
C(51)-P(1)-C(1)
C(41)-P(1)-Au(1)
87.7(3)
88.8(2)
176.4(2)
176.83(17) C(61)-P(2)-C(3)
90.56(18) C(2)-P(2)-C(3)
92.90(18) C(61)-P(2)-Au(2)
88.6(3)
87.0(3)
C(51)-P(1)-Au(1)
C(1)-P(1)-Au(1)
C(61)-P(2)-C(2)
117.2(2)
113.9(2)
106.3(3)
105.6(3)
106.0(3)
108.8(2)
113.8(2)
115.6(2)
C(2)-P(2)-Au(2)
C(3)-P(2)-Au(2)
C(101)-P(3)-C(111) 109.4(3)
Figure 1. Molecular structure of complex 6. All H atoms have been
omitted.
174.3(3)
174.32(17) C(101)-P(3)-C(4)
106.3(3)
103.9(3)
91.0(2) C(111)-P(3)-C(4)
resonance, split at low temperature into three singlet resonances
with a very different chemical shift from those found in
complexes 10-11; this might indicate a bridging dithiocarbam-
ate ligand as has been previously reported in [Au2(µ-S2CNR2)-
(µ-dppe)](ClO4) (R ) Me, Et, CH2Ph; dppe ) 1,2-bis-
(diphenylphosphino)ethane)13,29 or in [Au3Cl2(S2CNR2)(µ-
dpmp)] (R ) Me, CH2Ph; dpmp ) bis(diphenylphosphinometh-
93.69(18) C(101)-P(3)-Au(3) 116.7(2)
C(111)-P(3)-Au(3) 107.6(2)
C(4)-P(3)-Au(3)
C(2)-C(1)-P(1)
112.2(2)
112.0(4)
116.5(4)
114.2(4)
112.1(4)
172.69(17) C(1)-C(2)-P(2)
89.81(18) C(4)-C(3)-P(2)
94.73(18) C(3)-C(4)-P(3)
108.8(3)
105.3(3)
100.8(3)
1
yl)phenylphosphine).30 The H NMR spectra at room temper-
ature involve two multiplets for ethylidene bridges in complexes
8-11 (2:6 ratio in the range 2.9-2.4 ppm) while three
resonances are observed in complexes 7 and 12-15 from 3.4
to 2.3 ppm; additionally, the resonances due to Fmes (around
8.2 ppm in complex 7), p-Me in complex 8, and the dithiocar-
bamate substituents (Me or CH2-) are found in the appropriate
ratio to the triphosphine proton resonances.
The LSIMS mass spectra show the peak corresponding to
[M - X]+ at m/z (complex, % abundance, X): 1688 (7, 5,
Fmes), 1371 (8, 100, SC6H4Me), 1241 (9, 100, SCN), 1366 (10,
31, S2CNMe2; 12, 52, Cl), 1669 (11, 41, S2CN(CH2Ph)2; 13,
19, Cl), 1281 (14, 100, Cl), 1432 (15, 93, Cl).
Crystal Structure of Complex 6. The geometry of the
trinuclear gold(III) complex [{Au(C6F5)3}3(µ-triphos)] has been
determined by X-ray diffraction. The molecular structure is
shown in Figure 1, with selected bonds and angles in Table 3.
The triphosphine adopts a conformation that allows three bulky
Au(C6F5)3 units to be coordinated at the same time. The gold
centers form a triangle with very long gold-gold distances:
7.095 Å for Au2-Au3, 8.348 Å for Au1-Au2, and 8.970 Å
for Au1-Au3, which precludes any form of metal-metal
bonding.
The gold(III) centers display slightly distorted square planar
coordination (mean deviations from best planes: Au1 0.02, Au2
0.07, Au3 0.09 Å) with CAuC and CAuP angles ranging from
87.0(3) to 94.73(18)°; the interplanar angles between the
coordination planes are 44° for Au1/Au2 and 86° for Au2/Au3.
Au-C bond distances trans to the phosphine lie in the range
2.047(7)-2.057(7) Å, whereas those trans to pentafluorophenyl
are 2.063(7)-2.079(7) Å. They are similar to those found in
other tris(pentafluorophenyl)gold(III) complexes, such as
110.0(2)
[Au(C6F5)3(S2C-PEt3)] (2.037(3) Å trans to S; 2.067(4) and
2.076(4)
trans to C),31 [(µ-S2C-PEt3){Au(C6F5)3}2]
Å
(2.048(16) and 2.058(20) trans to S, 2.062(14)-2.090(13) Å
trans to C),31 NBu4[{Au(C6F5)3PPh2CHPPh2}2Au] (2.063(8) and
2.080(8) trans to P, 2.057(8)-2.069(9) Å trans to C)32 or
[N(PPh3)2][{Au(C6F5)3(µ-PPh2)}2Au] (2.073(6) Å trans to P,
2.052(5) and 2.058(6) trans to C).33 Au(III)-P bond distances
range from 2.3434(17) to 2.3564(17) Å, slightly shorter than
those in NBu4[{Au(C6F5)3PPh2CHPPh2}2Au] (2.367(2) Å) or
in [N(PPh3)2][{Au(C6F5)3(µ-PPh2)}2Au] (2.365(2) Å) but longer
that those in [Au(C6F5)3{PPh2C(dCH2)PPh2}Au(C6F5)]
(2.382(2) Å)34 and similar to those found in AuMe3PPh3
(2.350(6) and 2.347(6) Å).35
Photophysical Characterization. The optical absorption
spectra in dichloromethane was measured for all the complexes,
and the most intense absorption was always around 230 nm
from the phenyl phosphine rings.30,36 The spectra of complexes
1, 3, 13, and 15 are plotted in Figure 2. Halo or organometallic
gold(I) derivatives 1-4 and 7 show an absorption around 270
nm that is only a shoulder in the spectra of 3 and 7; there is
absorption up to 300 nm except for the iodo derivative, which
shows an absorption at 300 nm. In the spectra of the pentafluo-
(31) Uso´n, R.; Laguna, A.; Laguna, M.; Castilla, M. L.; Jones, P. G.;
Fittschen, C. J. Chem. Soc., Dalton Trans. 1987, 3017.
(32) Ferna´ndez, E. J.; Gimeno, M. G.; Jones, P. G.; Laguna, A.; Laguna,
M.; Lo´pez-de-Luzuriaga, J. M. Organometallics. 1995, 14, 2918.
(33) Blanco, M. C.; Ferna´ndez, E. J.; Jones, P. G.; Laguna, A.; Lo´pez de
Luzuriaga, J. M.; Olmos, M. E., Angew. Chem., Int. Ed. 1998, 37,
3042.
(34) Ferna´ndez, E. J.; Gimeno, M. C.; Jones, P. G.; Laguna, A.; Lo´pez de
Luzuriaga, J. M.; Olmos, M. E. Chem. Ber. 1997, 130, 1513.
(35) Stein, J.; Fackler, J. P.; Paparizos, C.; Chen, H. W. J. Am. Chem.
Soc. 1981, 103, 2192.
(29) Bardaj´ı, M.; Laguna, A.; Laguna, M., J. Chem. Soc., Dalton Trans.
1995, 1255.
(30) Bardaj´ı, M.; Fischer, A. K.; Jones, P. G.; Laguna, A. Inorg. Chem.
2000, 39, 3560.
(36) King, C.; Wang, J.-C.; Khan, M. N. I.; Fackler, J. P. Jr. Inorg. Chem.
1989, 28, 2145.

2680 Inorganic Chemistry, Vol. 40, No. 12, 2001
Bardaj´ı et al.
Figure 2. Absorption spectra in dichloromethane solution of complexes
1, 3, 13, and 15.
Figure 3. Solid-state excitation and emission spectra of the triphosphine
(- - -) and complexes 2 (‚-‚-) and 3 (s) at room temperature.
rophenyl gold(III) derivatives 5-6, an intense aborption at about
256 nm is observed in addition to the phenyl absorption at 232
nm; again there is absorption up to 300 nm. Thiolate and
thiocianate derivatives 8-9 show a shoulder about 260 nm;
absorption continues up to about 400 nm for 8 or 350 nm for
9. In dithiocarbamate gold(I) derivative spectra, the main
features are the following: (a) again an intense phenyl absorp-
tion at 230 nm; (b) an absorption at 260 nm for methyl
dithiocarbamate derivatives 10, 12, 14 or at 270 nm for benzyl
dithiocarbamate derivatives 11, 13, 15, which becomes less
intense when the proportion of dithiocarbamate diminishes and
has previously been assigned to these ligands;13 (c) shoulders
around 300-330 nm, more clearly seen for complex 10 at 296
nm and for complex 14 at 325 nm; in any case there is
absorption up to around 400 nm. The absorptions in the range
300-350 nm can be assigned to sulfur to gold or to metal-
centered transitions as reported for other phosphine-thiolate
gold(I) derivatives13,30,37 and for trinuclear tris(phosphine)
gold(I) derivatives.28,38,39
Figure 4. 77 K solid-state excitation and emission spectra of the
triphosphine (‚-‚-) and complexes 2 (thick s), 6 (- - -), and 15 (s).
Table 4. Emision and Excitation Maxima (in nm) Measured for the
The solid-state emission and excitation spectra for the
triphosphine and complexes 1-15 have been determined at 298
and 77 K, and the results are summarized in Table 4. It is very
important to note that sodium dithiocarbamate or thiocianate
salts do not emit in the visible range, but the triphosphine does.
There is an emission centered at 425 nm, while the excitation
has a broad profile in the range 240-290 nm which must be
related to π-π* phenyl ring transitions; at low temperature the
excitation and emission spectra have the same profile and
maxima. If the excitation frequency is higher than 310 nm, there
is almost no emission. In Figure 3 are plotted the solid-state
excitation and emission spectra of the triphosphine and com-
plexes 2 and 3 at room temperature. The solid-state excitation
and emission spectra of the triphosphine and complexes 2, 6,
and 15 at low temperature are plotted in Figure 4.
Triphosphine and Complexes 1-15 in the Solid State at 298 and 77
K
excitation
298 K
emission
298 K
excitation
77 K
emission
77 K
complex
triphos 240-290
425
240-290
330
335
340
325
425
1
440
455
460
450
2
3
350
385
475
525
4
5
6
7
8
340
370
450, 455 345
485
430
495
420 (sh), 460
555
255
385
350
9
475
10
11
12
13
14
455, 460
450
440 (sh), 455 550
415, 425 530
600
The bromo and iodo derivatives 2 and 3 emit at room
temperature with an important red-shift from the free triphos-
phine (50 nm for 2 and 100 nm for 3), the excitation maxima
being centered at 350 and 385 nm, respectively, again strongly
red-shifted from the triphosphine. Curiously, the chloro, pen-
405 (sh), 430, 520
450 (sh)
405 (sh), 415 520
15
395, 410 (sh) 515
tafluorophenyl, and tris(trifluoromethyl)phenyl derivatives 1, 4,
and 7 do not emit, even on using an excitation frequency below
300 nm. The luminescence properties are thus dramatically
influenced by the halide anions, which indicates an important
contribution of the halides in the energy levels involved in the
electronic transitions, as described for other trinuclear gold(I)
(37) Narayanaswamy, R.; Young, M. A.; Parkhurst, E.; Ouellette, M.; Kerr,
M. E.; Ho, D. M.; Elder, R. C.; Bruce, A. E.; Bruce, M. R. M. Inorg.
Chem. 1993, 32, 2506.
(38) Bardaj´ı, M.; Laguna, A.; Orera, V. M.; Villacampa, M. D. Inorg. Chem.
1998, 37, 5125.
(39) Li, D.; Che, C.; Peng, S.; Liu, S.; Zhou, Z.; Mak, T. C. W. J. Chem.
Soc., Dalton Trans. 1993, 189.

Synthesis of Luminescent Au(I) and Au(III) Complexes
Inorganic Chemistry, Vol. 40, No. 12, 2001 2681
derivatives28,40 At low temperature, complexes 1-4 and 7 emit
with the maxima in the range 430-460 nm. In the series chloro,
bromo, and iodo there is a slight red-shift in the excitation (330,
335, and 340 nm, respectively) and in the emission (440, 455,
and 460 nm) and thus luminescence is slightly influenced by
the halide anions, implying a totally different electronic transi-
tion nature. It is noteworthly that the Fmes derivative 7 is the
most intense with respect to both excitation and emission
spectra, whose profile and maxima are close to that of the
triphosphine but much more intense. These data at low tem-
perature provide evidence for a ligand-centered transition
modified by the anionic ligands and the gold(I) centers, as has
been already proposed for the series [{AuXPPhMe2}n] (X )
Cl, Br, I; n ) 2, 3),41 [AuX(ER3)] (X ) Cl, Br; E ) P, As),42
or [Au10{µ-PPh2N(nPr)PPh2}4(µ3-S)4](PF6)2,43 instead of metal-
centered transitions usually proposed in most luminescent
triphosphine or diphosphine gold(I) complexes.28,39,44
Gold(III) complexes 5-6 have also been studied. The
dinuclear derivative 5 emits neither at room temperature nor at
low temperature, whereas the trinuclear derivative 6 emits at
both temperatures. In comparison to the ligand spectra, not only
are the excitation maxima red-shifted (by a minimum of 50 nm)
but also the emission maxima (by 25 nm at room temperature
and 60 nm at low temperature). In this case we cannot assign
the emission clearly to the triphosphine, because the tris-
(pentafluorophenyl)gold(III) units play a decisive role. The
number of such units has a dramatic influence in the lumines-
cence properties which in the absence of any gold(III)-
gold(III) contact seems to be associated to different molecular
geometries and different isomers (as discussed above).
because sulfur to gold, or more generally ligand to metal
transitions, in some cases shifted by gold-gold interactions,
could be involved as proposed for mononuclear or dinuclear
phosphine-thiolate gold(I) complexes.11-13
Dithiocarbamate derivatives 10-15 do not emit at room
temperature except in the case of complex 14 containing only
a methyl dithiocarbamate; the excitation and emission maxima
(430 and 520 nm, respectively) are totally different from those
found for the triphosphine but similar to those of some
diphosphine or triphosphine dithiocarbamate derivatives. At low
temperature all the complexes emit, the emission maxima being
in the range 515-600 nm and the excitation maxima from 395
to 460 nm; in both types of spectra the maximum diminishes
with the number of dithiocarbamate ligands, as we described
for the analogous derivatives with the triphosphine dpmp (which
has CH2 bridges intead of CH2CH2 in triphos).30 This fact can
be explained because raising the number of dithiocarbamate
ligands that can interact with the gold(I) centers to give
tricoordinated gold(I) leads to a splitting of orbitals and
consequently to a red shift of the emission maxima. Complex
14 (with one methyl dithiocarbamate) is strongly luminescent
while complexes 10 and 11 (with three dithiocarbamates) and
13 (with two benzyl dithiocarbamates) are weakly luminescent.
In conclusion, we have prepared luminescent derivatives
whose emission maxima range from 450 to 520 at room
temperature and from 430 to 600 nm at low temperature. Some
of them are strongly luminescent (7, 9, and 14 at low
temperature and 9 at room temperature) although most of them
do not emit at room temperature and only 5 does not emit at
low temperature. We can tentatively assign the nature of the
emission as related to mainly a ligand (triphosphine) centered
excited state for complex 7 to mainly a ligand to metal centered
excited state for dithiocarbamate derivatives 10-15, with most
of the cases being very difficult to assign because several kinds
of electronic transitions are plausible, and probably they are
superimposed.
Thiolate derivative 8 does not emit at room temperature,
whereas thiocyanate derivative 9 emits intensely with a maxi-
mum at 475 nm (excitation maximum at 370 nm). At low
temperature complex 9 also emits intensely, with the maxima
slightly blue-shifted. Complex 8 becomes luminescent at low
temperature, the excitation and emission maxima being red-
shifted compared to the previous values described in this paper.
Here the assignment of the emissions is even more complicated,
Acknowledgment. We thank the Direccio´n General de
Investigacio´n Cient´ıfica y Te´cnica (Project PB97-1010-C02-
01) and the Fonds der Chemischen Industrie for financial
support. We also thank Dr. J. Galba´n (Universidad de Zaragoza,
Spain) for helpful discussions. This work is dedicated to Prof.
Rafael Uso´n on the occasion of his 75th birthday.
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Supporting Information Available: An X-ray crystallographic file
in CIF format for the structure determination of complex 6. This
material is available free of charge via the Internet at http://pubs.acs.org.
(44) Field, J. S.; Grieve, J.; Haines, R. J.; May, N.; Zulu, M. M. Polyhedron
1998, 17, 3021.
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