Complexes with S-donor ligands. 5. ? Syntheses of the first (hydrosulfido)- and anionic sulfidoorganogold(I) complexes. Crystal and molecular structure of (Et4N)2[{Au(C6F5)} 3(μ3-S)]·0.5MeC(O)Et

Article abstract of DOI:10.1021/om970106b

Complexes Q[Au(R)Cl] react with H₂S in the presence of diethylamine to give the corresponding organo(hydrosulfido)gold(I) complexes Q[Au(R)(SH)] [R = C₆F₅, Q = Ph₃P=N=PPh₃ = PNP, Bu₄N; Q = PNP, R = C₆H₄NO₂-2, C₆H₂(NO₂)₃-2,4,6]. Under the same reaction conditions, Me₄N[Au(C₆F₅)Cl] gives the bridging organo(μ₃-sulfido)gold(I) complex (Me₄N)₂[{Au(C₆F₅)} ₃(μ₃-S)], whereas Et₄N[Au(C₆F₅)Cl] gives Et₄N[Au(C₆F₅)SH] or (Et₄N)₂[{Au(C₆F₅)} ₃(μ₃-S)] depending on the workup procedure. The crystal structure of Et₄N-[{Au(C₆F₅)}₃(μ ₃-S)]·0.5MeC(O)Et has been determined. The Au?Au contacts are 3.1844, 3.2773, and 3.4772 A?, with corresponding angles 86.68, 90.31, and 97.65° at sulfur.

Full text of DOI:10.1021/om970106b

Organometallics 1997, 16, 3381-3387
3381
Com p lexes w ith S-Don or Liga n d s. 5.† Syn th eses of th e
F ir st (Hyd r osu lfid o)- a n d An ion ic Su lfid oor ga n ogold (I)
Com p lexes. Cr ysta l a n d Molecu la r Str u ctu r e of
(Et4N)2[{Au (C6F 5)}3(µ3-S)]‚0.5MeC(O)Et
J ose´ Vicente,*,‡ Mar´ıa-Teresa Chicote,* Pablo Gonza´lez-Herrero, and
Claus Gru¨nwald§
Grupo de Quı´mica Organometa´lica, Departamento de Qu´ımica Inorga´nica,
Facultad de Quı´mica, Universidad de Murcia, Apartado 4021, Murcia, 30071 Spain
Peter G. J ones*,|
Institut fu¨r Anorganische und Analytische Chemie, Technische Universita¨t Braunschweig,
Postfach 3329, 38023 Braunschweig, Germany
Received February 11, 1997X
Complexes Q[Au(R)Cl] react with H2S in the presence of diethylamine to give the
corresponding organo(hydrosulfido)gold(I) complexes Q[Au(R)(SH)] [R ) C6F5, Q )
Ph3PdNdPPh3 ) PNP, Bu4N; Q ) PNP, R ) C6H4NO2-2, C6H2(NO2)3-2,4,6]. Under the
same reaction conditions, Me4N[Au(C6F5)Cl] gives the bridging organo(µ3-sulfido)gold(I)
complex (Me4N)2[{Au(C6F5)}3(µ3-S)], whereas Et4N[Au(C6F5)Cl] gives Et4N[Au(C6F5)SH] or
(Et4N)2[{Au(C6F5)}3(µ3-S)] depending on the workup procedure. The crystal structure of Et4N-
[{Au(C6F5)}3(µ3-S)]‚0.5MeC(O)Et has been determined. The Au‚‚‚Au contacts are 3.1844,
3.2773, and 3.4772 Å, with corresponding angles 86.68, 90.31, and 97.65° at sulfur.
In tr od u ction
complex, PNP[Au(SH)2],15 (PNP ) Ph3PdNdPPh3) which
is thought to be involved in the geological transport
of gold.16-19 In this paper we report the first organo-
gold(I) hydrosulfido complexes, Q[Au(R)(SH)], whose
stability/reactivity depends on the nature of the coun-
terion Q.
A large number of transition-metal complexes with
sulfide ligands have been reported. These complexes
have found applications as catalysts.4,5,20,21 However,
the number of sulfidogold complexes is very limited.
Thus, a family of complexes [(AuPR3)n(µn-S)](n-2)+ is
known for n ) 2-6 and various phosphine or diphos-
phine ligands.22-28 The further coordinating ability of
the sulfido ligand in [{Au2(dppf)}(µ2-S)] [dppf ) 1,1′-
bis(diphenylphosphino)ferrocene] or [(AuPPh3)2(µ2-S)]
has allowed the synthesis of the mixed complexes [{Au2-
Transition-metal hydrosulfido complexes are under
intensive investigation mainly because of the reactivity
they exhibit toward organic substrates,1,2 their implica-
tion in catalytic biological3 or hydrodesulfuration4-6
processes, and their use as models in theoretical studies7
and as a source of complexes containing terminal sulfido
ligands.8 About 100 such complexes have been de-
scribed, the most common being those of Mo9-11 and
Ru.12-14 We have described the synthesis and crystal
structure of the first homoleptic hydrosulfido metal
† For part 4, see: Vicente, J .; Chicote, M. T.; Rubio, C. Chem. Ber.
1996, 129, 327.
‡ E-mail: jvs@fcu.um.es.
§ On leave from the Institut fu¨r Anorganische Chemie der Univer-
sita¨t Wu¨rzburg, Germany.
| E-mail: jones@xray36.anchem.nat.tu-bs.de.
X Abstract published in Advance ACS Abstracts, J une 15, 1997.
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15, 3631.
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1992, 13, 28.
(23) Canales, F.; Gimeno, C.; Laguna, A.; Villacampa, M. D. Inorg.
Chim. Acta 1996, 244, 95.
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901.
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S0276-7333(97)00106-4 CCC: $14.00 © 1997 American Chemical Society

3382 Organometallics, Vol. 16, No. 15, 1997
Vicente et al.
Hg(OAc)2 (2.30 g, 7.22 mmol). Immediately, a bulky white
precipitate of Hg(O2CC6H4NO2-2)2 formed, which was stirred
for 0.5 h, filtered off, washed with water (20 mL), and dried
in vacuo at 110 °C for 1 h. This product was decarboxylated
by heating at 190 °C for 5 h in an open tube. After the mixture
was cooled to room temperature, the resulting off-white solid
was extracted with dichloromethane (5 × 25 mL). The
combined extracts were filtered through Celite, the solvent was
evaporated to dryness, and the residue was stirred in diethyl
ether (40 mL) for 0.5 h to give the title compound as a pale
yellow solid, which was filtered off and air dried. Yield: 753
mg, 28%. The melting point and IR spectrum coincide with
those previously described.41 Anal. Calcd for C12H8HgN2O4:
C, 32.40; H, 1.81; N, 6.23. Found: C, 32.44; H, 1.75; N, 6.28.
(dppf)}(AuC6F5)(µ3-S)] or [{Au2(dppf)}(AuCH2PPh3)(µ3-
S)] or [(Au2L2){Au(C6F5)3}2(µ4-S)] (L ) PPh3, L2
)
dppf).22,29 As far as we are aware, these are the only
sulfido complexes involving organogold moieties. We
report here the first fully organogold sulfido complex,
[(AuC6F5)3(µ3-S)]2-, which is, along with [Au12S8]4-
,
[Au2S8]2-, and [AuS9]-,30 the only anionic sulfidogold(I)
complex.
The formation of complexes [(AuPR3)n(µn-S)](n-2)+
,
including the hypercoordinated species with n ) 5 and
6, is an example of the tendency of AuPR3+ moieties to
aggregate at interstitial atoms (C, P, N) to give interest-
ing compounds with unusual structure and bonding,
whose stability is attributed to a relativistic effect on
Au(I) energy levels termed “aurophilicity”.31-38 It should
be borne in mind that the successive aggregation of each
AuL+ unit at sulfur causes the charge of the resulting
complex to increase by one unit, with concomitant
increases in electrostatic repulsion effects and instabil-
ity. Therefore, the aurophilic effect, which has been
quantified to about 33 kJ /mol, must play an important
role in these reactions.33 It seemed of interest to
establish whether neutral AuR units could show some
tendency to aggregate at small interstitial atoms. Ac-
cording to electronic and steric effects the resulting
anionic complexes (e.g. [(AuR)n(µn-S)]2-) should be more
prone to act as ligands than the cationic complexes
[(AuPPh3)n(µn-S)]n+ and should therefore aggregate AuR
or AuL+ units more readily.
Syn th eses of Q[Au (C6F 5)Cl] [Q ) P NP (1‚P NP ), Me4N
(1‚Me4N)]. To a solution of [Au(C6F5)(tht)] (tht ) tetrahy-
drothiophene) (ca. 1 mmol) in acetone (10 mL) was added an
equimolar amount of QCl, and the resulting solution or
suspension was stirred for 0.5 (1‚P NP ) or 1 (1‚Me4N) h and
then filtered through anhydrous MgSO4. The filtrate was
concentrated (3 mL) and diethyl ether (15 mL) added to
precipitate 1‚P NP or 1‚Me4N as white solids which were
filtered off, washed with diethyl ether (25 mL) and dried in a
nitrogen stream. 1‚P NP : Yield: 79%. Mp: 136 °C dec ΛM:
94 Ω-1 cm2 mol-1
. .
IR: ν(AuCl) 328 (vs) cm-1 19F NMR
(CDCl3, δ): -164.78 (m, 2 F, m-F), -163.56 (m, 1 F, p-F),
-115.30 (m, 2 F, o-F). Anal. Calcd for C42H30AuClF5NP2: C,
53.78; H, 3.22; N, 1.49. Found: C, 53.94; H, 3.07; N, 1.50.
1‚Me4N: Yield: 90%. Mp: 186 °C dec ΛM: 135 Ω-1 cm2 mol-1
.
IR: ν(AuCl) 318 (vs) cm-1 19F-NMR (CDCl3, δ): -164.41 (m,
.
2 F, m-F), -163.55 (m, 1 F, p-F), -115.14 (m, 2 F, o-F). Anal.
Calcd for C10H12AuClF5N: C, 25.36; H, 2.55; N, 2.96. Found:
C, 25.38; H, 2.44; N, 2.91.
Exp er im en ta l Section
Syn th esis of P NP [Au (C6H4NO2-2)Cl] (2). A mixture of
PNP[AuCl2] (834 mg, 1.04 mmol), [Hg(C6H4NO2-2)2] (298 mg,
0.67 mmol), and Me4NCl (270 mg, 2.46 mmol) in acetone (50
mL) was refluxed for 5 h. After the mixture was cooled to room
temperature, the solvent was evaporated to dryness and the
black residue refluxed in dichloromethane for 0.5 h. The
suspension was filtered through anhydrous MgSO4 and the
clear yellow filtrate concentrated to 3 mL under vacuum.
Addition of ethanol (20 mL) led to slow precipitation of 2 as a
pale yellow solid which was filtered off and air dried. The
product was recrystallized from dichloromethane and diethyl
ether. Yield: 303 mg, 33%. Mp: 147 °C dec ΛM: 92 Ω-1 cm2
mol-1. IR: ν(AuCl) 314 (m); νasym(NO2) 1504 (s) cm-1. NMR
(CDCl3, δ): 1H, 6.96 (m, 1 H, C6H4NO2-2), 7.17 (m, 1 H, C6H4-
NO2-2), 7.41-7.69 (m, 31 H, C6H4NO2-2 + PNP), 7.71 (m, 1
H, C6H4NO2-2); 13C{1H} 122.63 (s), 123.16 (s), 130.80 (s), 142.48
(s, C3-C6, C6H4NO2-2), 150.36 (s, C1, C6H4NO2-2), 158.13 (s,
C2, C6H4NO2-2). Anal. Calcd for C42H34AuClN2O2P2: C, 56.48;
H, 3.84; N, 3.14. Found: C, 56.32; H, 3.81; N, 3.23.
All reactions were carried out in normal laboratory condi-
tions. Technical grade solvents were purified by standard
procedures. Infrared spectra were recorded in the range
4000-200 cm-1 on a Perkin-Elmer 16F PC FT-IR spectropho-
tometer using Nujol mulls between polyethylene sheets.
Conductivities were measured on ca. 5 × 10-4 M acetone
solutions with a Philips PW9501 conductimeter. Melting
points were determined on a Reichert apparatus and are
uncorrected. C, H, N, and S analyses were carried out with a
Carlo Erba 1106 microanalyzer. NMR spectra were measured
in a Varian Unity 300 spectrometer. Chemical shifts are
referred to TMS [1H and 13C{1H}] or CFCl3 (19F). The integra-
tion of the signal corresponding to the SH proton is always
less than expected, probably because of its greater relaxation
time with respect to the other protons. The 13C resonances of
PNP+ (PNP ) Ph3PdNdPPh3) appear, with little differences
between the various complexes, at δ 127 (dd of an AA′XX′
system, J CP ) 108 and 0.8 Hz, i-C), 130 (m, o-C), 132 (m, m-C)
and 134 (s, p-C) and are not given below. [Hg{C6H2(NO2)3-
2,4,6}2],39 [Au(C6F5)(tht)] (tht ) tetrahydrothiophene), Et4N-
[Au(C6F5)Cl], and Bu4N[Au(C6F5)Cl] were prepared as previ-
ously described.40
Syn th esis of P NP [Au {C6H2(NO2)3-2,4,6}Cl] (3). A mix-
ture of PNP[AuCl2] (478 mg, 0.59 mmol), [Hg{C6H2(NO2)3-
2,4,6}2] (203 mg, 0.33 mmol), and (Me4N)Cl (220 mg, 2.01
mmol) in acetone (20 mL) was refluxed for 5 h. After the
mixture was cooled to room temperature, the solvent was
evaporated to dryness and the black residue refluxed in
dichloromethane (20 mL) for 15 min. The suspension was
filtered through anhydrous MgSO4 and the clear red filtrate
concentrated to 3 mL. Addition of ethanol (20 mL) led to slow
precipitation of 3 as a greenish-yellow solid which was filtered
off, washed with ethanol (9 mL) and diethyl ether (6 mL), and
air dried. The product was recrystallized from dichlo-
romethane and ethanol. Yield: 520 mg, 89%. Mp: 132 °C.
ΛM: 85 Ω-1 cm2 mol-1. IR: ν(AuCl) 326 (m); νasym(NO2) 1530
Syn th esis of [Hg(C6H4NO2-2)2]. To a suspension of HO2-
CC6H4NO2-2 (2.01 g, 12.02 mmol) in water (60 mL) was added
(29) Canales, F.; Gimeno, M. C.; Laguna, A.; J ones, P. G. Organo-
metallics 1996, 15, 3412.
(30) Marbach, G.; Stra¨hle, J . Angew. Chem., Int. Ed. Engl. 1984,
23, 246, 715. Mu¨ller, A.; Romer, M.; Bo¨gge, H.; Krickemeyer, E.;
Schmitz, K. Inorg. Chim. Acta 1984, 85, L39.
(31) Schmidbaur, H. Chem. Soc. Rev. 1995, 391.
(32) Schmidbaur, H. Gold Bull. 1990, 23, 11.
(33) Schmidbaur, H.; Graf, W.; Mu¨ller, G. Angew. Chem., Int. Ed.
Engl. 1988, 27, 417.
(34) Scherbaum, F.; Grohmann, A.; Huber, B.; Kru¨ger, C.; Schmid-
baur, H. Angew. Chem., Int. Ed. Engl. 1988, 27, 1544.
(35) J ones, P. G. Gold Bull. 1981, 14, 102.
(36) J ones, P. G. Gold Bull. 1981, 14, 159.
(37) J ones, P. G. Gold Bull. 1983, 16, 114.
(38) J ones, P. G. Gold Bull. 1986, 19, 46.
(39) Kharash, M. S. J . Am. Chem. Soc. 1921, 43, 2238.
(40) Uso´n, R.; Laguna, A.; Vicente, J . J . Organomet. Chem. 1977,
131, 471.
(41) Nesmeyanov, A. N. Selected Works in Organic Chemistry;
Pergamon Press: Oxford, 1963.

Complexes with S-Donor Ligands
Organometallics, Vol. 16, No. 15, 1997 3383
(vs), 1518 (vs) cm-1. NMR (CDCl3, δ): 1H, 7.4-7.7 (m, 30 H,
PNP), 8.65 (s, 2H, C6H2(NO2)3-2,4,6); 13C{1H} 120.38 (s, C3,
C6H2(NO2)3-2,4,6), 143.71 (s, C1, C6H2(NO2)3-2,4,6), 155.94 and
159.59 (s, C2 and C4, C6H2(NO2)3-2,4,6). Anal. Calcd for
AuN2O2P2S: C, 56.63; H, 3.96; N, 3.15; S, 3.60. Found: C,
56.34; H, 4.34; N, 3.04; S, 3.70.
Syn th esis of P NP [Au {C6H2(NO2)3-2,4,6}(SH)] (6). To a
yellow solution of 3 (110 mg, 0.11 mmol) in dichloromethane
(4 mL) was added diethylamine (0.05 mL). H2S was bub-
bled through the resulting red solution until the color changed
to bright orange. Immediate addition of diethyl ether (40
mL) led to slow precipitation of a bright orange solid which
was filtered off, washed with water (2 × 1 mL) and diethyl
ether (20 mL), and air dried to give 6. Yield: 87 mg, 79%.
C
42H32AuClN4O6P2: C, 51.31; H, 3.28; N, 5.70. Found: C,
51.44; H, 3.36; N, 5.62.
Syn th esis of P NP [Au (C6F 5)(SH)] (4‚P NP ). H2S was
bubbled through a stirred solution of 1‚P NP (705 mg, 0.75
mmol) in a mixture of dichloromethane (10 mL) and diethyl-
amine (0.3 mL) for 3 min. The solvent was then evaporated
to ca. 5 mL and diethyl ether (10 mL) added to give a white
precipitate of (Et2NH2)Cl, which was removed by filtration
through anhydrous MgSO4. The clear filtrate was concen-
trated (3 mL) to precipitate 4‚P NP as a white solid which was
filtered off, washed with diethyl ether (10 mL), and dried in a
nitrogen stream. Yield: 605 mg, 86%. Mp: 136 °C. ΛM: 102
Ω-1 cm2 mol-1. IR: ν(Au-S) 338 (m); ν(C6F5) 1500 (vs), 948
Mp: 116 °C. ΛM: 91 Ω-1 cm2 mol-1. IR: ν(AuS) 334 (m); νasym
-
(NO2) 1530 (s), 1514 (s) cm-1. NMR (CDCl3, δ): 1H -1.09 (s,
1 H, SH), 7.4-7.7 (m, 30 H, PNP), 8.70 (s, 2H, C6H2(NO2)3-
2,4,6). 13C{1H} 120.65 (s, C3, C6H2(NO2)3-2,4,6), 143.42 (s,
C1, C6H2(NO2)3-2,4,6), 159.27 and 166.58 (s, C2 and C4,
C6H2(NO2)3-2,4,6). Anal. Calcd for C42H33AuN4O6P2S: C,
51.44; H, 3.39; N, 5.71; S, 3.27. Found: C, 51.55; H, 3.36; N,
5.74; S, 3.84.
(vs), 790 (s) cm-1
.
NMR (CDCl3, δ): 1H -1.16 (s, 1H, SH),
7.3-7.7 (m, 30 H, PNP); 19F -164.58 (m, 2 F m-F), -163.95
(m, 1 F p-F), -115.66 (m, o-F). Anal. Calcd for C42H31AuF5-
NP2S: C, 53.91; H, 3.34; N, 1.50; S, 3.43. Found: C, 53.68;
H, 3.23; N, 1.56; S, 3.77.
Syn th esis of (Me4N)2[{Au (C6F 5)}3(µ3-S)] (7‚Me4N). H2S
was bubbled through a stirred suspension of 1‚Me4N (165 mg,
0.35 mmol) in a mixture of acetone (5 mL) and diethylamine
(0.1 mL) for 4 min. Addition of diethyl ether (15 mL) to the
resulting solution gave a white precipitate which was removed
by filtration through anhydrous MgSO4. Partial evaporation
of the clear filtrate (3 mL) and addition of diethyl ether (15
mL) led to slow precipitation of 7‚Me4N as a white solid, which
was filtered off and air dried. Yield: 98 mg, 66%. Mp: 231
°C dec ΛM: 204 Ω-1 cm2 mol-1. IR: ν(Au-S) 366 (m), 312 (w);
ν(C6F5) 1504 (vs), 950 (vs), 790 (s) cm-1. NMR [(CD3)2CO, δ]:
Syn th esis of Bu 4N[Au (C6F 5)(SH)] (4‚Bu 4N). H2S was
bubbled through a stirred solution of Bu4N[Au(C6F5)Cl] (200
mg, 0.31 mmol) in a mixture of dichloromethane (4 mL) and
diethylamine (0.1 mL) for 3 min. The solvent was then
evaporated to ca. 3 mL and diethyl ether (15 mL) added to
give a white precipitate of (Et2NH2)Cl, which was removed by
filtration through anhydrous MgSO4. The clear filtrate was
concentrated (3 mL) to precipitate 4‚Bu 4N as a white solid.
n-Pentane (15 mL) was added to complete the precipitation of
4‚Bu 4N, which was filtered off and dried in a nitrogen stream.
2
1H, 3.45 (t, NMe4, J HN ) 6.0 Hz); 19F -164.35 (m, 3 F, m-F +
p-F), -114.36 (m, 2 F, o-F). Anal. Calcd for
C26H24-
Au3F15N2S: C, 24.54; H, 1.90; N, 2.20; S, 2.52. Found: C,
24.57; H, 2.09; N, 2.45; S, 3.06.
Yield: 178 mg, 89%. M.p.: 73 °C. ΛM: 112 Ω-1 cm2 mol-1
IR: ν(Au-S) 334 (m); ν(C6F5) 1500 (vs), 950 (vs), 790 (s) cm-1
.
.
Syn th esis of (Et4N)2[{Au (C6F 5)}3(µ3-S)] (7‚Et4N). H2S
was bubbled through a stirred solution of Et4N[Au(C6F5)Cl]
(1002 mg, 1.89 mmol) in a mixture of dichloromethane (10 mL)
and diethylamine (0.5 mL) for 5 min. Diethyl ether (35 mL)
was added to precipitate a white solid which was filtered off,
washed with water (10 mL), and air dried. The product was
then dissolved in acetone (15 mL) and the resulting solution
filtered through anhydrous MgSO4. Evaporation of the solvent
(ca. 6 mL) and addition of diethyl ether (30 mL) led to the
precipitation of 7‚Et4N as a white solid which was filtered off
and air dried. Yield: 700 mg, 80%. Mp: 176 °C dec ΛM: 186
Ω-1 cm2 mol-1. IR: ν(Au-S) 360 (m), 312 (w); ν(C6F5) 1496
(vs), 952 (vs), 790 (s) cm-1. NMR [(CD3)2CO, δ]: 1H, 1.35 (tt,
NMR (CDCl3, δ): 1H -1.19 (s, 1H, SH), 0.99 (t, 12 H, Me,
Bu4N), 1.42 (m, 8 H, CH2, Bu4N), 1.67 (m, 8 H, CH2, Bu4N),
3.27 (m, 8 H, CH2, Bu4N); 19F -163.83 (m, 2 F, m-F), -162.63
(m, 1 F, p-F), -116.30 (m, 2 F, o-F). Anal. Calcd for
C
22H37AuF5NS: C, 41.32; H, 5.83; N, 2.19; S, 5.01. Found: C,
41.18; H, 5.99; N, 2.26; S, 4.75.
Syn th esis of Et4N[Au (C6F 5)(SH)] (4‚Et4N). H2S was
bubbled through a stirred solution of Et4N[Au(C6F5)Cl] (151
mg, 0.28 mmol) in a mixture of acetone (5 mL) and diethyl-
amine (0.1 mL) for 3 min. A small amount of (Et2NH2)SH
formed as a white precipitate. Addition of diethyl ether (25
mL) caused the precipitation of (Et2NH2)Cl, which was re-
moved along with (Et2NH2)SH by filtration through anhydrous
MgSO4. The clear filtrate was concentrated (3 mL) and
n-pentane (20 mL) added to give a white precipitate of 4‚Et4N,
which was filtered off and dried in a nitrogen stream. Yield:
81 mg, 80%. Mp: 60 °C. IR: ν(Au-S) 332 (m); ν(C6F5) 1506
(vs), 952 (vs), 792 (s) cm-1. NMR (CDCl3, δ): 1H -1.17 (s, 1
H, SH), 1.38 (tt, Me, 12 H, 3J HH ) 7.2 Hz, 3J HN ) 2.0 Hz), 3.39
(q, 8 H, CH2); 19F -163.67 (m, 2 F, m-F), -162.23 (m, 1 F,
p-F), -116.66 (m, 2 F, o-F). Anal. Calcd for C14H21AuF5NS:
C, 31.89; H, 4.01; N, 2.66; S, 6.08. Found: C, 31.66; H, 4.00;
N, 2.64; S, 5.25.
Me, 3 H, 3J HH ) 7.2 Hz, 3J HN ) 2.0 Hz), 3.47 (q, CH2, 2 H); 19
F
-164.50 (m, 3 F, m-F + p-F), -114.19 (m, 2 F, o-F). Mass
spectrum (FAB): m/ z 383 (21), 531 ([Au(C6F5)2], 100), 760
([{Au(C6F5)}2(µ2-S)], 71), 761 (31), 957 (65), 1124 (M, 42), 1254
(51). Anal. Calcd for C34H40Au3F15N2S: C, 29.49; H, 2.91; N,
2.02; S, 2.32. Found: C, 29.62; H, 2.93; N, 2.03; S, 2.50. Single
crystals were grown by slow diffusion of diethyl ether into a
MeC(O)Et solution of 7‚Et4N.
Syn th esis of (Bu 4N)2[{Au (C6F 5)}3(µ3-S)] (7‚Bu 4N). Com-
plex 7‚Me4N (106 mg, 0.08 mmol) and (Bu4N)Cl (48 mg, 0.17
mmol) were mixed in dichloromethane (8 mL). The resulting
suspension was stirred for 1 h and filtered through anhydrous
MgSO4 to remove the white precipitate of (Me4N)Cl. Partial
evaporation of the filtrate (3 mL) and addition of diethyl ether
(20 mL) gave a small amount of a white solid, which was
removed by filtration through anhydrous MgSO4. Partial
evaporation of the clear filtrate (5 mL) led to the precipitation
of 7‚Bu 4N as a white solid which was filtered off and dried in
a nitrogen stream. Yield: 58 mg, 43%. Mp: 123 °C. ΛM: 142
Ω-1 cm2 mol-1. IR: ν(Au-S) 364 (m), 310 (w); ν(C6F5) 1500
(vs), 950 (vs), 788 (s) cm-1. NMR [(CD3)2CO, δ]: 1H, 0.94 (t,
Me, Bu4N, 3 H), 1.42 (m, CH2, Bu4N, 2 H), 1.79 (m, CH2, Bu4N,
2 H), 3.44 (m, CH2, Bu4N, 2 H); 19F -164.63 (m, m-F, p-F),
-113.95 (m, o-F). Anal. Calcd for C50H72Au3F15N2S: C, 37.32;
H, 4.51; N, 1.74; S, 1.99. Found: C, 37.69; H, 4.59; N, 1.79; S,
2.26.
Syn th esis of P NP [Au (C6H4NO2-2)(SH)] (5). H2S was
bubbled through a stirred solution of 2 (120 mg, 0.13 mmol)
in a mixture of dichloromethane (4 mL) and diethylamine (0.2
mL) for 4 min. Immediate addition of diethyl ether (20 mL)
to the resulting yellow solution led to the precipitation of a
yellow solid which was filtered off, washed with water (2 × 1
mL) and diethyl ether (2 × 5 mL), and air dried to give 5.
Yield: 101 mg, 85%. Mp: 135 °C. ΛM: 91 Ω-1 cm2 mol-1. IR:
ν(AuS) 330 (m); νasym(NO2) 1504 (s) cm-1
. NMR (CDCl3, δ):
1H -1.30 (s, 1H, SH), 6.96 (m, 1H, C6H4NO2-2), 7.22 (m, 1H,
C6H4NO2-2), 7.3-7.7 (m, 31H, PNP + C6H4NO2-2), 7.78 (m,
1H, C6H4NO2-2); 13C{1H} 122.71 (s), 122.95 (s), 130.86 (s),
142.19 (s, C3-C6, C6H4NO2-2), 158.16 (s, C1, C6H4NO2-2),
163.20 (s, C2, C6H4NO2-2). Anal. Calcd for C42H35
-

3384 Organometallics, Vol. 16, No. 15, 1997
Vicente et al.
Ta ble 1. Cr ysta l Da ta for 7‚Et4N‚0.5MeC(O)Et
Sch em e 1
molecular formula
molecular weight
source
C36H44Au3F15N2O0.5
1420.69
liquid diffusion MeC(O)Et/Et2O
prism
S
description
colour
colorless
crystal system
a, Å
b, Å
orthorhombic
30.346(5)
47.526(9)
12.009(2)
17319(5)
c, Å
V, Å3
Z
16
radiation (λ, Å)
temperature, K
monochromator
space group
crystal size, mm3
µ, mm-1
absorption correction
max. transmission, %
min. transmission, %
diffractometer type
data collection method
2θ range, min.-max.
hkl limits
Mo KR (0.710 73)
173(2)
graphite
Fdd2
0.40 × 0.25 × 0.20
10.882
Psi scans
0.91
0.63
Siemens P4
ω scans
6.1-50.0
-36 < h < 0
-56 < k < 0
-14 < l < 14
7616
7615
0.007
previously described.41 However, it involves a tedious
multistep procedure starting from o-nitroaniline, which
in our hands gives yields no higher than 18%. Taking
advantage of the procedure described by Kharash for
the synthesis of the analogous complex [Hg{C6H2(NO2)3-
2,4,6}2],39 we have prepared [Hg(C6H4NO2-2)2] by de-
carboxylation of the corresponding mercury(II) o-ni-
trobenzoate (Scheme 1), this procedure being not only
much simpler but also allowing a higher yield.
reflections measured
independent refelctions
Rint
R1(I > 2σI), wR2a
0.0411, 0.0806
a
R1 ) σ||Fo| - |Fc||/σ|Fo|. wR2 ) [σ[w(Fo2 - Fc2)2]/σ[w(Fo2)2]]0.5
.
Syn th esis of (P NP )2[{Au (C6F 5)}3(µ3-S)] (7‚P NP ). Com-
plex 7‚Me4N (75 mg, 0.06 mmol) and PNPCl (71 mg, 0.12
mmol) were mixed in dichloromethane (8 mL). The resulting
suspension was stirred for 1 h and filtered through anhydrous
MgSO4 to remove the white precipitate of (Me4N)Cl. Partial
evaporation of the filtrate (3 mL) and addition of diethyl ether
(20 mL) gave a colorless oil. After decantation of the mother
liquor, the oil was dried in vacuo to give 7‚P NP as a white
solid. Yield: 103 mg, 81%. ΛM: 187 Ω-1 cm2 mol-1. Mp: 64
°C. IR: ν(Au-S) 362 (w); ν(C6F5) 1494 (vs), 950 (vs), 786 (s)
cm-1. NMR [(CD3)2CO, δ]: 1H, 7.5-7.8 (m, PNP+); 19F -165.16
(m, p-F), -164.71 (m, m-F), -113.89 (m, o-F). Anal. Calcd
for C90H60Au3F15N2P4S: C, 49.11; H, 2.75; N, 1.27; S, 1.46.
Found: C, 49.22; H, 2.84; N, 1.48; S, 1.47.
X-Ray Str u ctu r e Deter m in ation of 7‚Et4N‚0.5MeC(O)Et.
Cr ysta l d a ta : C36H44Au3F15N2O0.5S, Mr ) 1420.69, orthor-
hombic, Fdd2, a ) 30.346(5) Å, b ) 47.526(9) Å, c ) 12.009(2)
Å, V ) 17 319 Å3, Z ) 16, Dx ) 2.179 mg m-3, λ(Mo KR) )
0.710 73 Å, µ ) 10.3 mm-1, F(000) ) 10 656, T ) -100 °C.
Da ta collection a n d r ed u ction : Colorless prism 0.45 × 0.25
× 0.2 mm, Siemens P4 diffractometer, ω scans, 7615 indepen-
dent reflections to 2θ 50°, absorption correction with ψ-scans
(transmissions 0.63-0.91). Str u ctu r e solu tion : direct meth-
ods. Str u ctu r e r efin em en t: Anisotropic on F2 (program
SHELXL-93, G. M. Sheldrick, University of Go¨ttingen), H
atoms using riding model, 357 restraints to local ring sym-
metry, and U components of neighboring light atoms, MeC-
(O)Et molecule disordered over a 2-fold axis. Absolute struc-
ture with “x” refinement [x ) -0.027(11)42]. Final Rw(F2)
0.081 for all reflections, 343 parameters, conventional R(F)
0.041, S 0.86, max. ∆F 0.90 e Å-3. See Table 1.
Complexes Q[Au(C6F5)Cl] [Q ) Ph3PdNdPPh3
)
PNP (1‚P NP ), Me4N (1‚Me4N)] have been prepared by
displacement of the labile tetrahydrothiophene (tht)
ligand present in [Au(C6F5)(tht)] with the corresponding
QCl salt, according to the procedure previously de-
scribed by one of us for the syntheses of the analogous
1‚NEt4 and 1‚NBu 4 salts.40 The preparation of com-
plexes PNP[Au(R)Cl] [R ) C6H4NO2-2 (2), C6H2(NO2)3-
2,4,6 (3)] (Scheme 1) has been achieved by transmeta-
lation reactions from the corresponding [HgR2] and
[AuCl2]- complexes. This method has been previously
described by us for the syntheses of the corresponding
+
PhCH2PPh3 salts (R ) C6H5NO2-2,43 C6H2(NO2)3-
2,4,6,44 C6F545).
Rea ction s of [Au (R)Cl]- Com p lexes w ith SH2.
We have studied the reactions of H2S with complexes
[Au(R)Cl]- [R ) C6F5 (1), C6H4NO2-2 (2), C6H2(NO2)3-
2,4,6 (3)] containing various cations in attempts to
obtain single crystals of the products. However, bub-
bling H2S through solutions of Q[Au(R)Cl] complexes
in a mixture of dichloromethane or acetone and dieth-
ylamine gives complexes Q[Au(R)(SH)] [R ) C6F5
(4‚P NP , 4‚Bu 4N, 4‚Et4N), C6H4NO2-2 (5), C6H2(NO2)3-
2,4,6 (6)] or Q2[{Au(C6F5)}3(µ3-S)] (7‚Me4N, 7‚Et4N)
depending on the reaction conditions and, to our sur-
prise, also on Q. Thus, whereas complexes containing
the PNP or Bu4N cations lead always to hydrosulfido
complexes 5, 6, 4‚P NP , 4‚Bu 4N, complex 1‚Me4N gives
always the sulfido complex 7‚Me4N. When the cation
is Et4N, the product obtained is 4‚Et4N or 7‚Et4N,
depending on the reaction conditions.
The programs use the neutral atom scattering factors, ∆f ′
and ∆f ′′ and absorption coefficients from International Tables
for Crystallography (Volume C, 1992; Wilson, A. J . C., Ed.;
Kluwer Academic Publishers: Dordrecht; Tables 6.1.1.4 (pp
500-502), 4.2.6.8 (pp 219-222) and 4.2.4.2 (pp 193-199),
respectively.
(42) Flack, H. D. Acta Crystallogr. 1983, A39, 876
(43) Vicente, J .; Arcas, A.; Chicote, M. T. J . Organomet. Chem. 1983,
252, 257.
(44) Vicente, J .; Arcas, A.; J ones, P. G.; Lautner, J . J . Chem. Soc.,
Dalton Trans. 1990, 451.
(45) Vicente, J .; Bermudez, M. D.; Chicote, M. T.; Sanchez-Santano,
M. J . J . Organomet. Chem. 1989, 371, 129.
Resu lts a n d Discu ssion
Syn t h esis of t h e Ar ylgold (I) Com p lexes [Au -
(R)Cl]-. The synthesis of [Hg(C6H4NO2-2)2] has been

Complexes with S-Donor Ligands
Organometallics, Vol. 16, No. 15, 1997 3385
Sch em e 2
solvent evaporated after 2 h and this procedure repeated
10 times, the resulting mixture contains 7‚P NP in
addition of 4‚P NP (by NMR). The reaction of 4‚P NP
with Ag2CO3 (2:1) giving 7‚P NP and Ag2S can also be
understood using equilibrium 3. Similarly, an acetone
solution of 4‚Bu 4N led to a mixture containing 4‚Bu 4N
and 7‚Bu 4N and other unidentified products after
stirring for 24 h. To prove the existence of 7‚P NP and
7‚Bu 4N in the above-mentioned mixtures, we prepared
them independently by reacting 7‚Me4N with the
corresponding chloride salts. Chloroform or acetone
solutions of 4‚Et4N led to a white precipitate of 7‚Et4N
or, respectively, solutions containing 7‚E t 4N (19F
NMR).
P r op er ties of [Au (R)(SH)]- a n d [{Au (C6F 5)}2(µ2-
S)]2- Com p lexes. Although in the solid state all Q[Au-
(R)(SH)] complexes here described smell of H2S, the
PNP salts are stable and can be stored at room tem-
perature for several weeks, after which time a pale
yelow color develops. Complex 4‚Bu 4N must be kept
at -20 °C, because otherwise it decomposes to give an
unidentified yellow oil after 1 day at room temperature.
In the solid state, 4‚Et4N changes into an orange solid
after a few days, even when stored at -20 °C. However,
when this orange material is dissolved in acetone-d6,
the 19F{1H} NMR spectrum shows only the presence of
7‚Et4N. From the above comments it can be concluded
that the stability of the Q[Au(R)(SH)] complexes de-
creases with the size of the cation.
For the pentafluorophenyl complexes 4, addition of
diethyl ether to the resulting solutions causes selective
precipitation of (Et2NH2)Cl, which is removed by filtra-
tion while [Au(C6F5)(SH)]- complexes remain in solution
and are isolated by partial evaporation of the solvent
(4‚P NP ) or addition of n-pentane (4‚Bu 4N, 4‚Et4N). The
synthesis and isolation of 4‚Et4N must be rapid because
it is rather unstable, even in the solid state, undergoing
H2S evolution. It was first obtained (33% yield) in a
gram-scale reaction meant to prepare complex 7‚Et4N.
In the synthesis of complexes 5 and 6, addition of diethyl
ether causes the precipitation of these complexes along
with (Et2NH2)Cl. These mixtures can be freed from the
ammonium salt by washing with water. When Et2NH
is added to a yellow solution of PNP[Au{C6H2(NO2)3-
2,4,6}Cl], the solution color changes to red, probably
associated with the presence of a new species that we
have not been able to characterize. After a few minutes
of bubbling H2S through this red solution, the color
turns to a bright orange. At this point immediate
addition of diethyl ether is required to precipitate
complex 6. If the addition of diethyl ether is delayed,
the color of the solution changes back to red and then
addition of diethyl ether causes the precipitation of a
mixture of unidentified products that does not contain
6 (by NMR).
Given that complexes 4 and 7 are white solids, the
yellow or orange materials formed by decomposition of
solid complexes 4 could contain the intermediate in the
decomposition process 4 f 7 that we assume to be the
Q2[{Au(C6F5)}2(µ2-S)] complex (not isolated; see Scheme
2). This complex would decompose rapidly to 7 as
shown in the case of 4‚Et4N. The FAB spectrum of
4‚Et4N shows the presence of this dinuclear species as
the second strongest peak. Consistent with the postu-
lated instability of Q2[{Au(C6F5)}2(µ2-S)] complexes, we
have failed in all attempts to prepare them indepen-
dently. Thus, the reactions of PNP[Au(C6F5)Cl] with
Li2S (2:1 in EtOH) gives 7‚P NP plus other unidentified
products and that of PNP[Au(C6F5)(SH)] with PNP[Au-
(C6F5)Cl] + Tl(acac) (1:1:1 in acetone) gives 7‚P NP ,
PNP[Au(C6F5)2], and unreacted PNP[Au(C6F5)(SH)].
The behavior of complexes Q[Au(R)Cl] contrasts with
that of [AuCl(PR3)] (R ) Ph, PhMe-4, PhOMe-4) when
they are reacted with H2S in the presence of diethyl-
amine. In the first case, complexes Q[Au(R)(SH)] and/
or Q2[{Au(C6F5)}3(µ3-S)] are obtained and µ2-S com-
plexes cannot be isolated, whereas in the second case
only [(AuPR3)2(µ2-S)] complexes are obtained.
We have also failed in all attempts to prepare deriva-
tives of complexes 4 and 7. Thus, [Au(C6F5)(tht)]
reacts with 4‚P NP or 7‚Et4N to give mainly Au2S and
Q[Au(C6F5)2]. Complex [Au(OClO3)(PPh3)] reacts with
7‚Et4N (1:1) or (2:1) to give [Et4N][Au(C6F5)2] + [Au-
(C6F5)(PPh3)] + Au2S or, respectively, an unstable
product that decomposes into metallic gold. The in-
ability of these hydrosulfido and sulfido complexes to
aggregate AuC6F5 or AuPPh3+ units contrasts with the
behavior observed in complexes [(AuPR3)n(µn-S)](n-2)+
and with our expectations.
Rea ction P a th w a y. It is reasonable to assume that
reactions 1 and 2 in Scheme 2 are common steps when
bubbling H2S through solutions containing Et2NH and
Q[Au(R)Cl] complexes. When R ) C6F5, the equilibrium
3 is displaced more or less to the right and is established
more or less quickly, depending on the nature of Q. The
major influence of the cation on this equilibrium is
surprising. Thus, we have never observed the formation
of trinuclear complexes 7 when starting from 1‚P NP
or 1‚Bu 4N. We could obtain no evidence for the forma-
tion of the intermediate complex Me4N[Au(C6F5)(SH)];
however, the existence of the equilibrium 3 is proved
for 4‚P NP because if it is dissolved in acetone, the
Complex 7‚P NP is obtained when 4‚P NP is reacted
t
with BuNC (1:1 acetone, 29 h) or with acetylene (1.5

3386 Organometallics, Vol. 16, No. 15, 1997
Vicente et al.
+
calculated for S(AuPH3)3 using relativistic potentials
[Au‚‚‚Au, 3.05, 3.52 Å; Au-S-Au, 82.3, 98,5°].48
The gold atoms are in essentially linear environments
with CAuS angles of 176.6(4)°, 177.0(3)°, and 177.7(3)°.
The Au(I)-S distances [2.319(4), 2.301(4), and 2.321(4)
Å] are similar to those found for the above mentioned
complexes [(AuPR3)3(µ3-S)]X and [Au{(µ3-S)(AuPPh3)2}2]+
[range 2.303(7)-2.342 (7) Å].26,27,46,47 The Au(I)-S
distances increase with the number of gold atoms
attached to sulfur. Thus, for complex 7‚Et4N they are
intermediate between those found in [{Au(PPh3)}2(µ2-
S)] [2.161 (5) and 2.157 (5) Å]49 and in [{Au(PPh3)}4(µ4-
S)].28 This fact can be related to the corresponding
decrease in the energy observed for the corresponding
ν(Au-S) IR bands (see below).23
The solid state IR spectra of the complexes Q[Au(R)-
(SH)] 4-6 are almost identical to those of the corre-
sponding Q[Au(R)Cl)] derivatives used as starting ma-
terials, except for the absence of the strong absorption
assigned to ν(Au-Cl) [1‚P NP , 328; 1‚Me4N, 318; Et4N-
[Au(C6F5)Cl],40 318; 2, 314; 3, 326 cm-1] and the
presence of a new medium to weak band in the 330-
340 cm-1 region (4‚P NP , 338; 4‚Bu 4N, 334; 4‚Et4N, 332;
5, 330; 6, 334 cm-1) that can reasonably be assigned to
ν(Au-S). The IR-active band in the 2300-2600 cm-1
region corresponding to the ν(SH) mode is not observed;
its weakness is a common feature in most SH complexes,
including PNP[Au(SH)2].15 The trinuclear complexes
Q2[S(AuC6F5)3] (7) show bands assignable to ν(Au-S)
at 362 (w) (7‚P NP ), 366 (m) and 312 (w) (7‚Me4N),
360 (m) and 312 (w) (7‚Et4N) or 364 (m) and 310 (w)
(7‚Bu 4N) cm-1 in agreement with data reported for
some related [(AuL)3(µ3-S)]+ complexes.23
F igu r e 1. ORTEP plot of 7‚Et4N‚0.5MeC(O)Et with the
labeling scheme. Selected bond lengths (Å) and angles
(°): Au(1)-S, 2.301(4); Au(2)-S, 2.321(4); Au(3)-S, 2.319-
(4); Au(1)-Au(2), 3.2773(9); Au(1)-Au(3), 3.4772(9); Au-
(2)-Au(3), 3.1844(9); Au(1)-C(11), 2.017(14); Au(2)-C(21),
2.019(14); Au(3)-C(31), 2.042(13). Au(1)-S-Au(2), 90.31-
(13); Au(1)-S-Au(3), 97.65(13); Au(2)-S-Au(3), 86.68(12);
C(11)-Au(1)-S, 176.6(4); C(21)-Au(2)-S, 177.7(3); C(31)-
Au(3)-S, 177.0(3).
bar, CH2Cl2, 3 days; along with PNP[Au(C6F5)2]). Com-
plex mixtures (mainly containing PNP[Au(C6F5)Cl]) are
always obtained when 4‚P NP is reacted with Cl2IPh.
The attempted reactions of 7‚Et4N with an excess of
CS2, or yellow HgO or MeI, led to recovery of the
starting material along with small amounts of Et4N-
[Au(C6F5)2].
After 3 days in CDCl3 solution, the nitrophenyl
complex 5 does not decompose, whereas the trinitro-
phenyl 6 does so only to a limited extent. The synthesis
of complexes Q[Au(C6H5NO2-2)Cl], with Q ) Et4N,
Me4N, was attempted following the same method used
with the PNP salt, but the products decompose to
metallic gold. This is a new example of the influence
of the size of the cation on the stability of an anionic
complex. Et4N[Au{C6H2(NO2)3-2,4,6}Cl] reacts with
H2S in CH2Cl2/Et2NH to give a mixture of complexes
that we could not separate.
Complexes 1, 4, and 7, bearing the C6F5 group, show
characteristic strong absorptions,50 at around 1500, 950,
and 790 cm-1 and nitrophenyl complexes 5 and 6 those
corresponding to νasym(NO2) absorptions at 1504 (5) or
1530, 1514 (6) cm-1 43
The corresponding νsym(NO2)
.
bands have diagnostic utility because they are sensitive
to the coordination mode of the nitrophenyl ligands.
They appear at around 1330 cm-1 for monocoordinate
O2NC6H4 ligands and shift to 1260 cm-1 when the
ligand coordinates through carbon and oxygen. In
complexes 5 and 6, unfortunately, these bands cannot
be assigned because they are obscured by the presence
of strong bands in the 1320-1220 cm-1 region from the
PNP cations. Although we have described complexes
of Pd,51 Pt,52 and Rh53 with monocoordinate or chelating
nitrophenyl ligands, we have always failed in our
attempts to coordinate the nitro group to gold(I) or -(III);
thus, we assume that the nitrophenyl ligands are
monodentate and that complexes 5 and 6 are linear two-
coordinate, the most common geometry for gold(I)
complexes. PNP salts show bands at around 1580 (m),
1320-1220 (s, br), 544 (s), 527 (s), 491 (s). The expected
absorptions from the cations Me4N, Bu4N, and Et4N
St r u ct u r e of Com p lexes: Cr yst a l St r u ct u r e of
[NEt4]2[S(AuC6F5)3]‚0.5MeC(O)Et (see Figure 1). The
sulfur atom is in a distorted trigonal pyramidal envi-
ronment with short Au‚‚‚Au contacts and, correspond-
ingly, narrow Au-S-Au angles. Two of these pairs of
parameters [Au‚‚‚Au, 3.1844 (9), 3.2773 (9) Å; Au-S-
Au, 86.68(12)°, 90.31(13)°] are in the normal range
observed for related gold(I) complexes [(AuPR3)3(µ3-S)]X
i
(R ) Ph, X ) PF6,26 BF4,27 R ) Me, Pr, Ph2Me, X )
BF446) or [Au{(µ3-S)(AuPPh3)2}2]+,47 [Au‚‚‚Au, 2.990(1)-
3.420(1); Au-S-Au, 79.5(1)(6)-95.0(3)], whereas one
pair lies outside the range [Au‚‚‚Au, 3.4772 (9) Å; Au-
S-Au, 97.65(13)°]. Therefore, it seems that the auro-
philic interactions are similar or slightly weaker in
(48) Pyykko¨, P.; Angermaier, K.; Assmann, B.; Schmidbaur, H. J .
Chem. Soc., Chem. Commun. 1995, 1889.
(49) Lensch, C.; J ones, P. G.; Sheldrick, G. M. Z. Naturforsch. 1982,
37B, 944.
(50) Long, D. A.; Steele, D. Spectrochim. Acta 1961, 19, 1955.
(51) Vicente, J .; Chicote, M. T.; Martin, J .; Artigao, M.; Solans, X.;
Font-Altaba, M.; Aguilo´, M. J . Chem. Soc., Dalton Trans. 1988, 141.
(52) Vicente, J .; Chicote, M. T.; Martin, J .; J ones, P. G.; Fittschen,
C.; Sheldrick, G. M. J . Chem. Soc., Dalton Trans. 1986, 2215.
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+
7‚Et 4N than in its homologues containing AuPPh3
groups, in spite of the differences in charge and size of
the groups attached to the gold atom. All of the above
values of Au‚‚‚Au, and Au-S-Au are similar to those
(46) Angermaier, K.; Schmidbaur, H. Chem. Ber. 1994, 127, 2387.
(47) J ones, P. G.; Lensch, C.; Sheldrick, G. M. Z. Naturforsch. 1982,
37B, 141.

Complexes with S-Donor Ligands
Organometallics, Vol. 16, No. 15, 1997 3387
around 950 cm-1 coincide with a very strong C6F5 band
in complexes 4 and 7.
NH, and Q[Au(R)Cl]. The nature of Q and the reaction
conditions influence the result. Complexes Q[Au(R)-
(SH)] are obtained for the larger cations [R ) C6F5, Q
) PNP, Bu4N; Q ) PNP, R ) C6H4NO2-2, C6H2(NO2)3-
2,4,6], whereas (Me4N)2[{Au(C6F5)}3(µ3-S)] is obtained
for the smallest cation. Et4N[Au(R)(SH)] or (Et4N)2-
[{Au(C6F5)}3(µ3-S)] can be obtained for the intermediate
cation. All attempts to prepare (PNP)2[{Au(C6F5)}2(µ2-
S)] gave (PNP)2[{Au(C6F5)}3(µ3-S)]. Other reactions,
attempting to use these hydrosulfido or sulfido com-
plexes as ligands to increase the coordination number
of the sulfur, failed. Among the possible reasons for this
could be the great stability of [Au(C6F5)2]- or [Au(C6F5)-
(PPh3)] complexes.
The 1H-NMR spectra of all the Q[Au(R)(SH)] com-
plexes show the resonance due to the SH protons
between -1.09 and -1.34 ppm [R ) C6F5, Q ) PNP
(-1.16 ppm), Bu4N (-1.19 ppm), Et4N (-1.17 ppm); R
) C6H4NO2-2 (-1.34 ppm); R ) C6H2(NO2)3-2,4,6 (-1.09
ppm)], suggesting that the withdrawing ability of the
R group decreases in the sequence C6H2(NO2)3-2,4,6 >
C6F5 > C6H4NO2-2. This signal appears in PNP[Au-
(SH)2] at δ ) -1.22 ppm and in most other hydrosulfido
complexes between δ ) +4 and δ ) -4 ppm.15 The 19F
NMR spectra of complexes 1 (CDCl3), 4 (CDCl3), and 7
(acetone-d6) show multiplets corresponding to o-F
(-113.89 to -116.66 ppm) and m-F (-163.67 to -165.16
ppm) at similar chemical shifts. The p-F multiplet
appears in 1 (CDCl3) and 4 (CDCl3) at an intermediate
frequency (-162.23 to -163.95 ppm) whereas in 7‚P NP
(CDCl3) it is observed at higher field overlapping with
the m-F multiplet (-165.20 ppm). This overlapping is
also observed in the spectra of 7‚Bu 4N, 7‚Me4N, and
7‚Et4N (acetone-d6) while in 7‚P NP (acetone-d6) the p-F
multiplet appears at higher field (-165.20 ppm) than
that of the m-F multiplet (-164.71 ppm).
Ack n ow led gm en t. We thank Direccio´n General de
Investigacio´n Cient´ıfica y Te´cnica (PB92-0982-C) and
the Fonds der Chemischen Industrie for financial sup-
port. P.G.-H. and C.G. thank Ministerio de Educacio´n
y Ciencia (Spain) for a Grant and the Deutsche Fors-
chungsgemeinschaft (SFB 347), respectively.
Su p p or tin g In for m a tion Ava ila ble: A listing of both
refined and calculated atomic coordinates, all the anisotropic
thermal parameters, and full bond lengths and angles for
compound 7‚Et4N‚0.5MeC(O)Et (7 pages). Ordering informa-
tion is given on any current masthead page.
Con clu sion s
Two types of complexes Q[Au(R)(SH)] and Q2[{Au-
(C6F5)}3(µ3-S)] have been isolated by reacting H2S, Et2-
OM970106B