Alkynyl derivatives of gold complexes containing C6H3-5-Me-2-EPh2 (E = P, As) ligands

Article abstract of DOI:10.1016/j.jorganchem.2010.03.027

[Au₂Cl₂{μ-2,2′-Ph₂As(5,5′-Me₂C₆H₃C₆H₃)AsPh₂}] reacts with phenylacetylene or ethynylferrocene to give the corresponding digold(I) bis(alkynyl) derivatives [Au₂(C{triple bond, long}CR)₂{μ-2,2′-Ph₂As(5,5′-Me₂C₆H₃C₆H₃)AsPh₂}] [R = Ph (4), Fc (5)]. In contrast, products resulting from the reaction with 1,3- or 1,4-diethynylbenzene (deb) depend markedly on the dichlorodigold(I) complex to ligand ratio. When an excess of alkyne is used, the expected bis(alkynyl) complexes [Au₂X₂{μ-2,2′-Ph₂As(5,5′-Me₂C₆H₃C₆H₃)AsPh₂}] [X = 1,3-deb (6), 1,4-deb (7)] are obtained, but when using a 1:1 molar ratio poorly soluble, presumably polymeric, species are formed. Attempts to prepare a digold(II) bis(alkynyl) derivative by treatment of [Au₂Cl₂(μ-C₆H₃-5-Me-2-PPh₂)₂] with ethynylferrocene in the presence of NaOMe gives a mixture of species, the recrystallization of which yielded a crystal of [{2-(FcC{triple bond, long}C)-4-MeC₆H₃PPh₂}Au(C{triple bond, long}CFc)] (1). The reaction of [Au₂Cl₂(μ-C₆H₃-5-Me-2-AsPh₂)₂] with phenylacetylene, 1,3- or 1,4-deb gives a mixture of unidentified products.

Full text of DOI:10.1016/j.jorganchem.2010.03.027

Journal of Organometallic Chemistry 695 (2010) 1787e1793
Contents lists available at ScienceDirect
Journal of Organometallic Chemistry
journal homepage: www.elsevier.com/locate/jorganchem
Alkynyl derivatives of gold complexes containing C6H3-5-Me-2-EPh2
(E ¼ P, As) ligands
,
b
a
a
Suresh K. Bhargava a , Kunihiko Kitadai , Nedaossadat Mirzadeh , Steven H. Privér ,
*
Masashi Takahashi b, Jörg Wagler c
a School of Applied Sciences (Applied Chemistry), RMIT University, GPO Box 2476V, Melbourne, Victoria 3001, Australia
b Department of Chemistry, Toho University, Chiba, Japan
c Institut für Anorganische Chemie, Technische Universität Bergakademie, Freiberg D-09596, Germany
a r t i c l e i n f o
a b s t r a c t
Article history:
[Au2Cl2{
m
-2,20-Ph2As(5,50-Me2C6H3C6H3)AsPh2}] reacts with phenylacetylene or ethynylferrocene to give
-2,20-Ph2As(5,50-Me2C6H3C6H3)
Received 28 January 2010
Received in revised form
12 March 2010
Accepted 23 March 2010
Available online 21 April 2010
the corresponding digold(I) bis(alkynyl) derivatives [Au2(C^CR)2{
m
AsPh2}] [R ¼ Ph (4), Fc (5)]. In contrast, products resulting from the reaction with 1,3- or 1,4-dieth-
ynylbenzene (deb) depend markedly on the dichlorodigold(I) complex to ligand ratio. When an excess of
alkyne is used, the expected bis(alkynyl) complexes [Au2X2{m
-2,20-Ph2As(5,50-Me2C6H3C6H3)AsPh2}]
[X ¼ 1,3-deb (6), 1,4-deb (7)] are obtained, but when using a 1:1 molar ratio poorly soluble, presumably
polymeric, species are formed. Attempts to prepare a digold(II) bis(alkynyl) derivative by treatment of
Keywords:
Gold alkynyl compound
Arsenic ligand
[Au2Cl2(
m-C6H3-5-Me-2-PPh2)2] with ethynylferrocene in the presence of NaOMe gives a mixture of
species, the recrystallization of which yielded a crystal of [{2-(FcC^C)-4-MeC6H3PPh2}Au(C^CFc)] (1).
The reaction of [Au2Cl2(
m
-C6H3-5-Me-2-AsPh2)2] with phenylacetylene, 1,3- or 1,4-deb gives a mixture of
Mössbauer spectroscopy
unidentified products.
Ó 2010 Elsevier B.V. All rights reserved.
1. Introduction
HC^N^CH ¼ 2,6-bis(4-t-butylphenyl)pyridine, R ¼ Ph] [11]. A series
of
gold(I)-gold(III)
complexes
of
the
type
[AuI(
m-
Transition metal alkynyl complexes have been extensively
studied over the past few decades owing to their potential applica-
tions as non-linear optical materials, molecular wires, molecular
electronics and luminescent materials [1]. Gold has been no
exception and since the first report of the explosive gold carbide
complex [AuCCH] [2], gold alkynyl chemistry has been the subject of
several reviews [3]. Gold(I) alkynyl complexes have been extensively
studied and often exhibit interesting luminescence behavior [4].
They have also been investigated for use as molecular wires [5] and
for their non-linear optical properties [6]. In sharp contrast to gold
(I), gold(III) alkynyl complexes are relatively uncommon and, to the
best of our knowledge, there are no reports of gold(II) alkynyl
complexes. Gold(III) complexes of the type [Au(C^CCF3)Me2(L)] (L
¼ PMe2Ph, PPh3) [7e9] and [Au(C^CR)Me2(PPh3)] (R ¼ H, Me) have
been prepared by Schmidbaur et al. [10] and the Yam group reported
the first examples of the luminescent behavior of gold(III) alkynyl
complexes of the type [Au(C^N^C)(C^CR)] [HC^N^CH ¼ 2,6-
diphenylpyridine, R ¼ Ph, C6H4-Cl-p, C6H4-OCH3-p, C6H4-NH2-p;
{CH2}2PPh2)2AuIII(C^CR)2] [R]Ph, tBu, SiMe3] has also been
reported, and represents the first fully characterized examples of
gold complexes containing two alkynyl ligands bound to a gold(III)
center [12].
The chemistry of dinuclear gold complexes of the type [Au2(
C6R4PPh2)2] (R ¼ H [13,14], F [17]) and [Au2( -C6H3-n-R-2-PPh2)2]
(R ¼ Me [15,16], F [17]; n ¼ 5, 6) has been explored for over two
decades. The complex [Au2( -C6H3-5-Me-2-PPh2)2] undergoes
m-2-
m
m
oxidative addition at the dimetal unit with one equivalent of
halogen to give, initially, the homodinuclear digold(II) complexes
[Au2X2(
m
-C6H3-5-Me-2-PPh2)2] (X ¼Cl, Br, I). The dihalodigold(II)
complexes are thermodynamically unstable, and on heating to ca.
50 ꢀC, rearrange to the CeC coupled digold(I) complexes [Au2X2{
m-
2,20-Ph2P(5,50-Me2C6H3C6H3)PPh2}] (X ¼ Cl, Br, I), as shown in
Scheme 1 [15].
The analogous arsenic-containing complexes [Au2(
Me-2-AsPh2)2] (n ¼ 5, 6) have also been investigated in detail [18].
The 5-methyl substituted complex [Au2( -C6H3-5-Me-2-AsPh2)2]
m-C6H3-n-
m
behaves similarly to its phosphorus analogue, undergoing oxidative
addition of halogens to give the symmetric dihalodigold(II)
complexes [Au2X2(
heating, rearrange to the CeC coupled products [Au2X2{
m
-C6H3-5-Me-2-AsPh2)2] (X ¼ Cl, Br, I), which, on
* Corresponding author. Tel./fax: þ61 3 9925 3365.
E-mail address: suresh.bhargava@rmit.edu.au (S.K. Bhargava).
m
-2,20-
0022-328X/$ e see front matter Ó 2010 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2010.03.027

1788
S.K. Bhargava et al. / Journal of Organometallic Chemistry 695 (2010) 1787e1793
Me
Me
Me
Ph2
PPh2
Au
PPh2
Au
P
Au
Au
X
X
X2
Δ
Au
Ph2P
X
Au
Ph2P
X
P
Ph2
X = Cl, Br, I
Me
Me
Me
Scheme 1. Reactivity of the digold(I) complex [Au2(m-C6H3-5-Me-2-PPh2)2].
Ph2As(5,50-Me2C6H3C6H3)AsPh2}] (X ¼ Cl, Br, I) [18]. As a logical
extension to this work, we were interested in the reactions of these
dichlorodigold complexes with various alkynes. Herein, we report
the syntheses, structures and characterization of a series of new
alkynylgold complexes. We also examine the reaction of the
dichlorodigold(II) complex [Au2Cl2(
m-C6H3-5-Me-2-PPh2)2] with
ethynylferrocene in the hope that it might lead to the formation of
the digold(II) alkynyl complex [Au2(C^CFc)2(m-C6H3-5-Me-2-
PPh2)2].
Fig. 1. Molecular structure of [{2-(FcC^C)-4-MeC6H3PPh2}Au(C^CFc)] 1. Ellipsoids
show 30% probability levels. Hydrogen atoms have been omitted for clarity. Selected
ꢀ
ꢀ
bond distances and angles: Au(1)eP(1) 2.2692(7) A, Au(1)eC(12) 2.ꢀ000(3) A, C(11)eC
ꢀ
ꢀ
(12) 1.197(4) A, C(32)eC(33) 1.195(4) A, P(1)eAu(1)eC(12) 177.19(8) .
2. Results and discussion
crystallography to be [{2-(FcC^C)-4-MeC6H3PPh2}Au(C^CFc)] (1).
The mechanism by which complex 1 is formed is not clear, however
it appears reductive elimination at the metal centers and coupling
of the aryl and alkynyl groups takes place, possibly via an unde-
tected gold(II) alkynyl intermediate. In addition, a peak at m/z 892
was observed in the FAB-mass spectrum of the mixture, corre-
sponding to the [M þ H]þ ion of 1.
2.1. Reactions of dinuclear gold(II) complexes
To prevent the facile rearrangement of the dichlorodigold(II)
complex, a dichloromethane solution of [Au2Cl2( -C6H3-5-Me-2-
m
PPh2)2] was cooled to ꢁ20 ꢀC and treated with an excess of ethy-
nylferrocene in the presence of NaOMe (Scheme 2). 31P NMR
spectroscopy showed that no reaction had taken place; it was not
until the solution was allowed to warm to room temperature that
the reaction proceeded. The 31P NMR spectrum of the isolated
The molecular structure of 1 (Fig. 1) shows the expected,
approximately linear, coordination about the gold(I) center, the
PeAueC angle being 177.19(8)ꢀ. The lengths of the two C^C bonds
orange solid showed four singlet resonances at
and 35.4, the first resonance being assigned to the known CeC
coupled digold(I) complex [Au2Cl2{
-2,20-Ph2P(5,50-Me2C6H3C6H3)
d 28.4, 30.5, 32.7
ꢀ
ꢀ
bound to the aryl group and gold atom [1.197(4) A and 1.195(4) A,
respectively] are identical, within experimental error. The AueP
m
ꢀ
ꢀ
and AueC distances [2.2692(7) A and 2.000(3) A, respectively] in 1
PPh2}]. The mixture could not be separated and the identities of the
other components have not been established. When the reaction
was performed at room temperature, a mixture of only two prod-
ucts was obtained, the 31P NMR spectrum of which showed two
ꢀ
are similar to those in [(Ph3P)Au(C^CC6F5)] [2.274(3) A and 1.993
(14) A, respectively] [19] and [{(FcC^C)Ph2P}Au(C^CFc)] [2.2779
(11) A and 2.000(5) A, respectively] [20]. The AueP distance of
2.2692(7) A is slightly longer than that in the structurally similar
ꢀ
ꢀ
ꢀ
ꢀ
singlet resonances at
d 39.4 and 35.7. Attempts to separate this
ꢀ
iodo analogue [AuI{Ph2P(C6H3-2-I-3-Me)}] [2.251(4) A] [15],
mixture by chromatography were unsuccessful. However, orange
crystals were obtained by diffusion of hexane into a dichloro-
methane solution of the mixture, which were shown by X-ray
consistent with the greater trans-influence of
s-carbon donor
ligands compared to iodide.
Me
PPh2
FcC CH
FcC CH
Cl
Au
Ph2P
Au
Cl
NaOMe
R. T.
NaOMe
°
-20
C
R. T
Me
Me
Me
Me
Ph2
P
Au Cl
Au Cl
PPh2
+ other species
+ other species
P
Ph2
C
Au
C
C
Fc
C
Fc
1
Scheme 2. Reaction of [Au2Cl2(m-C6H3-5-Me-2-PPh2)2] with ethynylferrocene.

S.K. Bhargava et al. / Journal of Organometallic Chemistry 695 (2010) 1787e1793
1789
Attempts to prepare other alkynylgold complexes by treatment
of [Au2Cl2( -C6H3-5-Me-2-PPh2)2] with phenylacetylene, 1,3- and
m
1,4-diethynylbenzene (deb) using a variety of bases (NaOMe, KOH
and NaOAc) resulted in inseparable mixtures of unidentified
products, as shown by 31P NMR spectroscopy.
The reaction of [Au2Cl2(m-2-C6H3-5-Me-AsPh2)2] with an excess
of ethynylferrocene in the presence of NaOMe or NaOAc at room
temperature gave an orange solid, which showed two methyl
resonances at
d
2.27 and 2.36 in its 1H NMR spectrum. Attempts to
separate these complexes were unsuccessful. The FAB-mass spec-
trum of this mixture showed two peaks at m/z 1243 and 936, which
may be due to the [M ꢁ C^CFc þ H]þ and [M þ H]þ ions of
[Au2(C^CFc)2(m-C6H3-5-Me-2-AsPh2)2] or more likely the rear-
ranged gold(I) compound [Au2(C^CFc)2{m
-2,20-Ph2As(5,50-
Me2C6H3C6H3)AsPh2}] (2), and [{2-(FcC^C)-4-MeC6H3AsPh2}Au
(C^CFc)] (3), respectively. The assignment of the peak at m/z 936 to
compound 3 is supported by the structural characterization of
compound 1 above. Reaction of [Au2Cl2(m-2-C6H3-5-Me-AsPh2)2]
with other acetylene derivatives (phenylacetylene, 1,3- and 1,4-
diethynylbenzene) using a variety of bases (NaOMe, KOH and
NaOAc) led only to a mixture of unidentified species with complex
1H NMR spectra.
Fig. 3. Molecular structure of [Au2(C^CFc)2{
5. Ellipsoids show 30% probability levels and hydrogen atoms have been omitted for
clarity. Only the ipso carbon atoms of the AsPh2 groups are shown.
m
-2,20-Ph2As(5,50-Me2C6H3C6H3)AsPh2}]
2.2. Reactions of dinuclear gold(I) complexes
analogues [15], and consist of a biphenyldiyl backbone with two
Ph2AsAuC^CR (R ¼ Ph, Fc) substituents in the 2 and 20 positions.
The biphenyldiyl groups in 4 and 5 are twisted about the central
The biphenyldiyl gold(I) complex [Au2Cl2{m
-2,20-Ph2As(5,50-
Me2C6H3C6H3)AsPh2}] reacted cleanly with phenylacetylene or
ethynylferrocene in the presence of NaOMe as base to afford the
CeC bond (the dihedral angle
substituents in anti- and syn-type configurations, respectively. The
a
being close to 90ꢀ) with the AsPh2-
expected alkynyl derivatives [Au2(C^CR)2{m
-2,20-Ph2As(5,50-
Me2C6H3C6H3)AsPh2}] [R ¼ Ph (4), Fc (5)] in yields of ca. 70%. The 1H
Au.Au separations of 3.2413(3) A and 3.0200(4) A in 4 and 5,
respectively, are significantly greater than those in [Au2X2{
-2,20-
Ph2As(5,5 -Me2C6H3C6H3)AsPh2}] [X ¼ Cl 2.9963(3) A, Br 2.9913
ꢀ
ꢀ
NMR spectra of complexes 4 and 5 each showed a single aromatic-
m
0
ꢀ
methyl resonance at ca.
d 1.8 and the FAB-mass spectra each
showed a peak corresponding to the [M ꢁ C^CR þ H]þ fragment.
The structures of 4 and 5 were confirmed by X-ray crystallography
and are shown in Figs. 2 and 3, respectively; selected bond lengths
and angles are summarized in Table 1.
ꢀ
ꢀ
(3) A, I 2.9932(3) A] [18], possibly due to crystal packing effects. In 4
and 5, the AseAu distances of ca. 2.38 A trans to the
ꢀ
s-carbon
ligands are longer than those found in their halide analogues
ꢀ
(2.34e2.36 A), consistent with the higher trans-influence of carbon
The molecular structures of 4 and 5 are similar to those of the
ligands compared to the halides.
m
-2,20-Ph2As(5,50-Me2C6H3C6H3)AsPh2}]
known dihalodigold(I) complexes [Au2X2{
Me2C6H3C6H3)AsPh2}] [X ¼ Cl, Br, I] and their phosphorus
m
-2,20-Ph2As(5,50-
Treatment of [Au2Cl2{
with five equivalents of 1,3- or 1,4-diethynylbenzene (deb) gave the
corresponding alkynyl derivatives [Au2R02{ -2,20-Ph2As(5,50-
m
Me2C6H3C6H3)AsPh2}] [R0 ¼ 1,3-deb (6); 1,4-deb (7)] (Scheme 3).
The 1H NMR spectra of 6 and 7 showed a single methyl resonance at
d
1.81 and 1.77, respectively, and the FAB-mass spectra each dis-
played a peak due to the [M ꢁ (deb) þ H]þ fragment. The structure
of 6 has been established by single-crystal X-ray diffraction (Fig. 4)
and selected bond distances and angles are listed in Table 2.
Table 1
Selected bond distances (A) and angles (ꢀ) in [Au2(C^CR)2{
Me2C6H3C6H3)AsPh2}] [R ¼ Ph (4), Fc (5)].
m
-2,20-Ph2As(5,50-
ꢀ
4
5
Au(1).Au(2)
Au(1)eAs(1)
Au(2)eAs(2)
Au(1)eC(8)
3.2413(3)
2.3791(4)
2.3839(5)
1.9936(17)
1.978(5)
Au(1).Au(2)
Au(1)eAs(1)
Au(2)eAs(2)
Au(1)eC(12)
3.0200(4)
2.3846(6)
2.3863(7)
1.968(5)
Au(2)eC(47)
Au(2)eC(51)
1.981(6)
As(1)eAu(1)eC(8)
As(1)eAu(1)eAu(2)
C(8)eAu(1)eAu(2)
As(2)eAu(2)eC(47)
As(2)eAu(2)eAu(1)
C(47)eAu(2)eAu(1)
a
171.16(7)
82.365(10)
104.02(8)
172.28(14)
84.558(11)
102.59(14)
87.88(13)
As(1)eAu(1)eC(12)
As(1)eAu(1)eAu(2)
C(12)eAu(1)eAu(2)
As(2)eAu(2)eC(51)
As(2)eAu(2)eAu(1)
C(51)eAu(2)eAu(1)
a
172.38(15)
83.271(14)
104.33(15)
169.04(16)
81.121(16)
109.81(16)
83.31(16)
Fig. 2. Molecular structure of [Au2(C^CPh)2{m
-2,20-Ph2As(5,50-Me2C6H3C6H3)AsPh2}]
4. Ellipsoids show 20% probability levels and hydrogen atoms have been omitted for
clarity.

1790
S.K. Bhargava et al. / Journal of Organometallic Chemistry 695 (2010) 1787e1793
Me
R
R
Me
Me
Ph2
Ph2
As Au
C
C
R'
R'
excess 1,3- or 1,4-deb
NaOMe
As Au Cl
As Au Cl
Ph2
As Au
Ph2
C
C
Me
R = CCH, R' = H 6
R = H, R' = CCH 7
Scheme 3. Reaction of [Au2Cl2{m
-2,20-Ph2As(5,50-Me2C6H3C6H3)AsPh2}] with an excess of 1,3- and 1,4-diethynylbenzene.
The molecular structure of 6 is similar to that of 4 and 5, with the
[22], [Au2(m-C6H4-2-PEt2)2] and [Au2(m-C6H4-2-PPh2)2] containing
biphenyl group in an anti-configuration with a dihedral angle
a
of
PeAueCaryl bonds [23].
.
ca. 85ꢀ. The Au Au separation [3.5210(4) A] is greater than those
found in 4 and 5, presumably to accommodate the bulkier ligands.
ꢀ
3. Conclusion
ꢀ
The AueAs distances [2.3697(5) and 2.3718(4) A] are only slightly
shorter than those observed in 4 and 5.
The biphenyldiyl digold(I) complex [Au2Cl2{m
-2,20-Ph2As(5,50-
In contrast to the reactions above, treatment of the biphenyldiyl
Me2C6H3C6H3)AsPh2}] reacts cleanly with phenylacetylene, ethy-
nylferrocene or with an excess of 1,3- or 1,4-diethynylbenzene
digold(I) complex [Au2Cl2{m
-2,20-Ph2As(5,50-Me2C6H3C6H3)AsPh2}]
with only one equivalent of 1,3- or 1,4-deb in the presence of
NaOMe in MeOH for 24 h gave yellow precipitates in high yields
(Scheme 4). These solids were insoluble in common organic
solvents, suggestive of polymeric species (8 and 9) although cyclic
structures of varying ring sizes cannot be ruled out.
(deb) to give the expected alkynyl derivatives [Au2(C^CR)2{m
-2,20-
Ph2As(5,50-Me2C6H3C6H3)AsPh2}] [R ¼ Ph (4), Fc (5)] and [Au2R02{
m-
2,20-Ph2As(5,50-Me2C6H3C6H3)AsPh2}] [R0 ¼ 1,3-deb (6), 1,4-deb
(7)], respectively. The structures of 4e6 have been confirmed by X-
ray crystallography. In contrast, treating the digold(I) complex
The polymeric material 9, obtained from the reaction of
[Au2Cl2{m
-2,20-Ph2As(5,50-Me2C6H3C6H3)AsPh2}] with a stoichio-
[Au2Cl2{m
-2,20-Ph2As(5,50-Me2C6H3C6H3)AsPh2}] with 1,4-deb, was
metric amount of 1,3- or 1,4-deb gives insoluble polymeric species.
Mössbauer spectroscopy of the latter product indicates all the gold
atoms are in identical environments and in the þ1 oxidation state.
analysed by Mössbauer spectroscopy and the spectrum and
parameters are shown in Fig. 5. The spectrum showed a well-
resolved quadrupole doublet, clearly indicating the gold atoms are
in identical environments. From the correlation plot (Fig. 6 and
Table 3), the oxidation state of the gold atom in this product was
determined to be þ1. The plot suggests that the gold atom is
coordinated by arsenic and carbon donor groups; both the I.S. and
Q.S. values are rather large, although the I.S. value is slightly smaller
than those of other gold(I) atoms coordinated to arsenic and
aromatic carbon atoms. A similar trend has been observed in
PeAueC systems; the I.S. values of [(Ph3P)AuC^CPh] and [(Ph3P)
AuC^C(1-hydroxy-cyclohexyl)] [21] containing the PeAueC^C
The reaction of the dichlorodigold(II) complex [Au2Cl2(m-C6H3-5-
Me-2-PPh2)2] with an excess of ethynylferrocene gives a mixture of
products, one of which is [{2-(FcC^C)-4-MeC6H3PPh2}Au(C^CFc)]
(1), as shown by X-ray crystallography.
4. Experimental
4.1. Physical measurements
1H NMR spectra were recorded on a JEOL JNM-ECP 400 or Varian
Gemini 300 NMR spectrometer as CDCl3 solutions, referenced to
residual solvent peaks. FAB-mass spectra were measured on a JEOL
JMS-600H spectrometer in positive ion mode. Elemental analyses
were carried out in-house on a PerkineElmer 2400 analyzer or at
the Microanalytical Laboratory of the Research School of Chemistry,
Australian National University.
fragment, are smaller than those of [Au2(m-C6H3-2-PPh2-6-Me)2]
Crystals suitable for single-crystal X-ray diffraction were
obtained by layering a dichloromethane solution of the complex
with hexane. All diffraction data were collected on a Bruker SMART
CCD area detector diffractometer with graphite monochromated
ꢀ
Mo-K
a
radiation (
l
¼ 0.71073 A). Geometric and intensity data
Table 2
ꢀ
m
-2,20-
ꢀ
Selected bond distances (A) and angles ( ) in [Au2(C^CC6H4-3-C^CH)2{
Ph2As(5,50-Me2C6H3C6H3)AsPh2] 6.
Au(1).Au(2)
Au(1)eAs(1)
Au(1)eC(10)
Au(2)eAs(2)
Au(2)eC(49)
3.5210(4)
2.3697(5)
1.984(5)
2.3718(4)
1.990(5)
As(1)eAu(1)eC(10)
C(23)eAs(1)eAu(1)
As(2)eAu(2)eC(49)
C(35)eAs(2)eAu(2)
a
174.26(14)
117.23(13)
173.78(16)
118.27(11)
85.25(13)
Fig.
4. Molecular
structure
of
[Au2(C^CC6H4-3-C^CH)2{m
-2,20-Ph2As(5,50-
Me2C6H3C6H3)AsPh2}] 6. Ellipsoids show 20% probability levels and hydrogen atoms
have been omitted for clarity.

S.K. Bhargava et al. / Journal of Organometallic Chemistry 695 (2010) 1787e1793
1791
Me
Me
Ph2
Ph2
R' Au As
1,3- or 1,4-deb
NaOMe
As Au Cl
Ph2
As Au R' Au As
As Au Cl
Ph2
Ph2
As Au R'
Ph2
n
R' = 1,3-deb2- 8, 1,4-deb2- 9
Scheme 4. Reaction of [Au2Cl2{m
-2,20-Ph2As(5,50-Me2C6H3C6H3)AsPh2}] with one equivalent of 1,3- or 1,4-diethynylbenzene.
Fig. 5. 197Au Mössbauer spectrum and parameters of compound 9 at 12 K.
were collected using SMART software [26]. The data were pro-
cessed using SAINT [27], and corrections for absorption were
applied using SADABS [28]. The data sets of 1, 4 and 5 were further
treated with a Xabs2 absorption correction as implemented in
WinGX [29]. All structures were solved by direct methods using the
SHELX-TL package [30]. Crystallographic data are summarized in
Table 4. The structure of 5 contains heavily disordered dichloro-
methane solvent of crystallization. After an initial refinement,
which revealed three sites in the asymmetric unit accessible to
solvent molecules, the data set was treated with SQUEEZE as
implemented in WinGX PLATON [31]. This procedure yielded 474
electrons per unit cell, corresponding to 118.5 electrons per
asymmetric unit (expected: 126 electrons corresponding to three
dichloromethane molecules). The crystallographic data have been
deposited at the Cambridge Crystallographic Data Center [CCDC
755 637 (4), 755 638 (6), 755 639 (1) and 755 640 (5)].
dichloromethane (10 mL) was treated with a 1.2-fold amount of
NaOMe in methanol. The mixture was shielded from light and
stirred overnight. The solution was evaporated to dryness and the
residue was washed with hexane and dried in vacuo to afford an
orange solid (26 mg). Attempts to separate the mixture were
unsuccessful, but an X-ray quality crystal of 1 was obtained by
11
B
C
E
10
9
D
G
O
F
A
Q-2
N
H
P-2
The gold-197 Mössbauer spectrum of 9 was acquired at Toho
University, Japan, on a Wissel Mössbauer spectrometer system
using previously reported experimental conditions [25]. The I.S.
values are given relative to the 197Pt/Pt source at 12 K.
8
7
M-1
I-1
J
P-1
L
4.2. Syntheses
Q-1
K
6
I-2
Most syntheses were performed under a dry argon atmosphere
with use of standard Schlenk techniques, although the solid gold
complexes, once isolated, were air-stable.
5
1
2
3
4
5
4.2.1. [{2-(FcC^C)-4-MeC6H3PPh2}Au(C^CFc)] (1)
I. S. (mm/s)
Fig. 6. Correlation plot for the gold(I) complexes listed in Table 3.
A stirred solution of [Au2Cl2(m-C6H3-5-Me-2-PPh2)2] (51 mg,
0.05 mmol) and ethynylferrocene (21 mg, 0.1 mmol) in

1792
S.K. Bhargava et al. / Journal of Organometallic Chemistry 695 (2010) 1787e1793
Table 3
and alkyne (0.09 mmol) in dichloromethane (10 mL) was treated with
197Au Mössbauer parameters for gold complexes.
a 1.2-fold amount of NaOMe in methanol. The mixture was shielded
from light and stirred overnight. The solution was evaporated to
dryness, the residue was washed with hexane and dried in vacuo to
afford the desired product as an orange solid.
Entry Compound
Au oxidation I.S.
state
Q.S.
(mm/s) (mm/s)
A
B
C
9
I
I
I
3.35
4.12
4.14
8.97
10.21
10.30
[(Ph3P)AuC^CPh]a
[(Ph3P)AuC^C(1-hydroxy-
cyclohexyl)]a
4 (R ¼ Ph): Yield: 43 mg, 70%. 1H NMR:
d 1.82 (s, 6H, Me), 6.12 (s,
2H, arom), 7.16e8.02 (m, 34H, arom). FAB-MS (m/z): 1135
[M ꢁ C^CPh þ H]þ, 837 [M ꢁ Au(CCPh)2 þ H]þ.
D
E
F
G
H
I
[Au2(
[Au2(
[Au2(
[Au2(
[Au2(
m
m
m
m
m
-C6H3-6-Me-2-PPh2)2]b
-2-C6H4PEt2)2]c
I
I
I
I
4.67
4.67
4.53
4.04
4.08
2.87
4.42
1.67
9.81
10.12
9.58
9.51
8.80
7.26
6.06
6.60
5 (R ¼ Fc): Yield: 46 mg, 74%. 1H NMR:
d 1.81 (s, 6H, Me),
-2-C6H4PPh2)2]c
4.15e4.51 (m, 18H, Cp), 6.08 (s, 2H, arom), 7.14e8.00 (m 24H, arom).
FAB-MS (m/z): 1244 [M ꢁ C^CPh þ H]þ. Anal. Calcd. For
C62H50Au2Fe2: C 51.34, H 3.47. Found: C 50.66, H 3.40.
-2-C6F4PPh2)2]d
-2-C6H4AsPh2)2]c
-2-C6H3-6-Me-2-PPh2)
I
[IAu(
m
I (site 1)
III (site 2)
I
(k
2-C6H3-6-Me-2-PPh2)AuI]b
4.2.3. [Au2R02{
(6), 1,4-deb (7)]
m
-2,20-Ph2As(5,50-Me2C6H3C6H3)AsPh2}] [R0 ¼ 1,3-deb
J
[Au2Cl2{
Me2C6H3C6H3)AsPh2}]e
[Au2Br2{
-2,20-Ph2As(5,50-
Me2C6H3C6H3)AsPh2}]e
[Au2I2{
-2,20-Ph2As(5,50-
Me2C6H3C6H3)AsPh2}]e
[ClAu( -2-C6H3-6-Me-2-AsPh2)
m
-2,20-Ph2As(5,50-
K
L
m
I
I
1.57
1.53
6.37
6.44
In an analogous reaction to that described above, treatment of
a
dichloromethane solution of [Au2Cl2{
m
-2,20-Ph2As(5,50-
m
Me2C6H3C6H3)AsPh2}] (55 mg, 0.05 mmol) and 1,3- or 1,4-dieth-
ynylbenzene (24 mg, 0.19 mmol) with a 1.2-fold amount of NaOMe
in methanol gave the title products as orange solids.
M
m
I (site 1)
III (site 2)
I
1.87
4.02
4.22
4.16
1.95
4.15
1.77
4.03
6.66
4.38
8.82
8.79
6.61
8.66
6.54
8.92
(k
2-C6H3-6-Me-2-AsPh2)AuCl]b
[Au2(
[Au2(
N
O
P
m
m
-C6H3-5-Me-2-AsPh2)2]e
-C6H3-6-Me-2-AsPh2)2]e
6 (R0 ¼ 1,3-deb): Yield: 36 mg, 56%. 1H NMR:
d 1.80 (s, 6H, Me),
I
3.14 (s, 2H, CCH), 6.1e8.0 (m, 34H, arom). FAB-MS (m/z): 1159
[M ꢁ deb þ H]þ. Anal. Calcd. For C58H42As2Au2: C 54.31, H 3.30.
Found: C 54.28, H 3.33.
[ClAu{
Au{AsPh2-2-Cl-3-Me-C6H3}]e
[BrAu{ -2-C6H3-6-Me-2-AsPh2}
Au{AsPh2(3-MeC6H4)}]e
m
-2-C6H3-6-Me-2-AsPh2}
I (site 1)
I (site 2)
I (site 1)
I (site 2)
Q
m
7 (R0 ¼ 1,4-deb): Yield: 29 mg, 45%. 1H NMR:
d 1.80 (s, 6H, Me),
a
b
c
Ref. [21].
3.10 (s, 2H, CCH), 6.1e7.9 (m, 34H, arom). FAB-MS (m/z): 1159
[M ꢁ deb þ H]þ.
Ref. [22].
Ref. [23].
Ref. [24].
Ref. [25].
d
e
4.2.4. Polymeric species 8 and 9
A stirred solution of [Au2Cl2{m
-2,20-Ph2As(5,50-Me2C6H3C6H3)
AsPh2}] (375 mg, 0.34 mmol) and 1,3- or 1,4-deb (44 mg,
0.35 mmol) in CH2Cl2 (40 mL) was treated with a 1.2-fold amount of
NaOMe in methanol and the mixture stirred overnight. The yellow
precipitate was isolated by filtration, washed with dichloro-
methane and hexane and dried in vacuo.
8: 308 mg, FAB-MS (m/z): 1476, 1369, 1159, 837.
9: 250 mg, FAB-MS (m/z): 1476, 1369, 1159, 837. Anal. Calcd. For
C48H36As2Au2: C 49.85, H 3.14. Found: C 48.98, H 2.86.
layering a dichloromethane solution with hexane. 31P NMR:
and 35.7.
d 39.4
4.2.2. [Au2(C^CR)2{
[R ¼ Ph (4), Fc (5)]
m
-2,20-Ph2As(5,50-Me2C6H3C6H3)AsPh2}]
In a similar reaction to that described above, a stirred solution of
[Au2Cl2{m
-2,20-Ph2As(5,50-Me2C6H3C6H3)AsPh2}] (55 mg, 0.05 mmol)
Table 4
Crystal data and details of data collection and structure refinement for complexes 1 and 4e6.
Compound
1
4
5
6
Formula
fw
C43H34AuFe2P
890.34
C54H42As2Au2
1234.65
C65H56As2Au2Cl6Fe2
1705.27
C58H42As2Au2
1282.69
Crystal system
Space group
Monoclinic
P21/n
17.0195(14)
10.4469(9)
19.9245(16)
90
106.596(2)
90
3395.0(5)
Monoclinic
C2/c
29.5545(18)
15.0123(9)
23.5493(14)
90
117.1380(10)
90
9298.1(10)
8
Monoclinic
P21/n
14.4181(11)
18.0381(13)
25.776(2)
Monoclinic
P21/n
18.4294(11)
13.4576(8)
19.8536(13)
90
92.7640(10)
90
4918.3(5)
ꢀ
a (A)
ꢀ
b (A)
ꢀ
c (A)
a
b
g
(ꢀ)
(ꢀ)
(ꢀ)
90
105.465(2)
90
6461.1(8)
3
ꢀ
V (A )
Z
4
4
4
Dcalc (mg mꢁ3
)
1.742
5.232
1.764
7.751
1.753
6.270
1.732
7.330
m
(mmꢁ1
)
T (K)
173(2)
298(2)
100(2)
293(2)
Cryst dimens (mm)
0.23 ꢂ 0.22 ꢂ 0.20
1.86e28.33
8427
0.40 ꢂ 0.28 ꢂ 0.22
1.56e28.34
11 528
0.31 ꢂ 0.30 ꢂ 0.17
1.64e28.40
16 103
0.54 ꢂ 0.27 ꢂ 0.26
1.47e28.35
36 326
Theta range (ꢀ)
Reflections collected
Unique (Rint
Data/restraints/parameters
)
24 520(0.0277)
8427/0/425
R1 ¼ 0.0238, wR2 ¼ 0.0548
R1 ¼ 0.0328, wR2 ¼ 0.0571
1.347, ꢁ0.735
34 146(0.0267)
11 528/4/488
R1 ¼ 0.0298, wR2 ¼ 0.0667
R1 ¼ 0.0583, wR2 ¼ 0.0729
1.075, ꢁ0.841
47 369(0.0806)
16 103/0/613
R1 ¼ 0.0417, wR2 ¼ 0.0774
R1 ¼ 0.0862, wR2 ¼ 0.0863
1.895, ꢁ1.539
36 326(0.0274)
12 212/0/562
R1 ¼ 0.0342, wR2 ¼ 0.0786
R1 ¼ 0.0612, wR2 ¼ 0.0848
1.419, ꢁ0.683
Final R indices [I > 2
s(I)]
R indices (all data)
Largest diff. peak and hole (e A
ꢀꢁ3
)

S.K. Bhargava et al. / Journal of Organometallic Chemistry 695 (2010) 1787e1793
1793
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Acknowledgements
A part of this work was supported by a Joint Research Project
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and also by the Inter-University Joint Program using JAEA Facilities.
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