Synthesis and Characterization of Gold Silyl Compounds with Different Phosphine or Phosphite Groups for Reduction Reactions

Article abstract of DOI:10.1002/ejic.201800595

The synthesis and structural characterization of metalloid gold clusters stabilized by sulfur ligands has increased massively in the last decade. The metalloid gold clusters are synthesized via a reduction of a gold precursor and most metalloid gold clusters are stabilized via aryl thiolate ligands. It is also possible to use thiosilyl or phosphine groups as stabilizing ligands. Here, we present a small Au₆ cluster as a possible intermediate of the formation of large metalloid clusters, together with the synthesis of a variety of defined Au^I precursors that contain a phosphine or a phosphite group as well as a thiosilyl ligand, which can be further used for the synthesis of metalloid gold clusters.

Full text of DOI:10.1002/ejic.201800595

A Journal of
Accepted Article
Title: Synthesis and characterization of gold silyl compounds with
different phosphine or phosphite groups for reduction reactions.
Authors: Sebastian Kenzler, Matthias Kotsch, and Andreas Bernd
Schnepf
This manuscript has been accepted after peer review and appears as an
Accepted Article online prior to editing, proofing, and formal publication
of the final Version of Record (VoR). This work is currently citable by
using the Digital Object Identifier (DOI) given below. The VoR will be
published online in Early View as soon as possible and may be different
to this Accepted Article as a result of editing. Readers should obtain
the VoR from the journal website shown below when it is published
to ensure accuracy of information. The authors are responsible for the
content of this Accepted Article.
To be cited as: Eur. J. Inorg. Chem. 10.1002/ejic.201800595
Link to VoR: http://dx.doi.org/10.1002/ejic.201800595

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
Table of content
Metalloid gold clusters stabilized with and without sulphur ligands are still investigated
thoroughly. Although, there are a lot of examples for the synthesis of such clusters, little is
known about the reaction mechanism or even the possibility of performing a planned
synthesis. In an attempt to close this gap, the synthesis of a small Au6 cluster is presented
together with a variety of defined Au(I) precursors for more precise reduction reactions to
obtain metalloid gold clusters.
Keywords: gold; metalloid cluster; phosphane
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
Synthesis and characterization of gold silyl compounds with different
phosphine or phosphite groups for reduction reactions.
Sebastian Kenzler,[a] Matthias Kotsch[a] and Andreas Schnepf[a]*
[*] Prof. Dr. A. Schnepf, Tel.: Int. Code +49 (7071) 29 – 76635; Fax: Int. Code +49 (7071) 28
– 2436; Email: andreas.schnepf@uni-tuebingen.de
a) Institut für Anorganische Chemie, Universität Tübingen, Auf der Morgenstelle 18, D-72076
Tübingen, Germany.
Dedicated to Professor Alexander C. Filippou on the occasion of his 60th birthday.
Abstract. The synthesis and structural characterization of metalloid gold clusters stabilized by
sulphur ligands has increased massively in the last decade. The metalloid gold clusters are
synthesized via a reduction of a gold precursor and most metalloid gold clusters are stabilized
via aryl thiolate ligands. It is also possible to use thiosilyl or phosphine groups as stabilizing
ligands. Here, we present a small Au6 cluster as a possible intermediate of the formation of
large metalloid clusters, together with the synthesis of a variety of defined Au(I) precursors that
contain a phosphine or a phosphite group as well as a thiosilyl ligand, which can be further
used for the synthesis of metalloid gold clusters.
Introduction
Gold has always been a driving force for chemistry. In early times alchemists tried to find the
lapis philosophorum, the philosopher’s stone, to transmute common metals into gold and silver.
As we know today this research was pointless but the countless attempts in this field of research
helped to develop a better understanding of metals, minerals and salts and also developed
different chemical methods and working techniques.[1]
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
Nowadays, the element gold still fascinates chemists and one area of particular interest is the
field of metalloid gold clusters. Metalloid clusters are clusters of the form MnRm (n > m) where
M depicts the metal and R the protecting ligands.[2] The synthesis of metalloid gold clusters
very often includes thiophenyl groups as sulphur ligands.[3,4,5,6,7,8,9] Probably, the most
prominent examples for metalloid gold clusters are those stabilized by sulphur ligands. Even
though, Brust et al. introduced a straightforward method to prepare robust solutions of gold
nanoparticles stabilized by sulphur ligands in 1994,[10] it took more than a decade until the first
huge metalloid gold cluster with sulphur ligands, Au102(p-MBA)44 (p-MBA = p-
mercaptobenzoic acid), could be structurally characterized via x-ray diffraction.[5] This cluster
consists of multiple shells of gold atoms, whereas the outermost shell is built up of so called
staple motifs of the form (RS-Au)n-SR (n = 1,2). The biggest structurally characterized
metalloid gold clusters to date are the recently described Au246(p-MBT)80 (p-MBT = 4-
methylbenzenethiolate) and Au279(TBBT)84 (TBBT = 4-tertbutylbenzenethiolate).[6,7] As one
can see, in each case a different ligand is used as well as different reaction conditions. Hence,
the synthetic route works quite well, if the right conditions are applied, although the reaction
mechanism is still unclear. In most cases HAuCl4 is reduced to an unknown species of the form
Aux(SR)y via the method introduced by Brust et al. Afterwards, further partly quite complicated
manipulations and work-up procedures are applied to obtain the final metalloid gold cluster.
During the reaction already within the first reaction step, where HAuCl4 is transferred into an
organic solvent, the composition of the Au(I) species is unknown.[7-9,11,12] On this ground the
established synthesis are mostly based on trial and error, leading to partly unusual experimental
procedures.[5-9] Hence, the questions how the building of the clusters proceeds, what properties
intermediates have and how the synthesis can be influenced to produce metalloid gold clusters
of any desired size are of central interest.
One possibility to get into this area is to start the reaction with a better-defined Au(I) compound
of the form R3PAuCl together with a thiol or to start with compounds of the composition
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
R3PAuSR` (R = organic substituent, R` = organic or metal-organic substituent). In those two
cases the gold atom already has the oxidation state +I, which may make it easier to specifically
reduce the compounds. For this reason, we present the synthesis and characterization of
different Au(I) species, which can be used for reduction reactions to produce metalloid gold
clusters, together with a small gold cluster, which might be seen as an intermediate in the
formation of larger metalloid gold clusters.
Results and Discussion
Recently, we could show that the reduction of the mixture of Ph3PAuCl / HSC(SiMe3)3 with
NaBH4 and the reduction of Ph3PAuSC(SiMe3)3 with LiBH(sec-Bu)3 led to the metalloid gold
clusters Au108S24(PPh3)16 and Au70S20(PPh3)12 respectively.[13,14] In both cases the sterically
demanding thiosilyl ligand SC(SiMe3)3 was used, showing that SC(SiMe3)3 acts as a sulphur
donating agent during the reaction as only sulphur atoms are present in the ligand shell of the
isolated metalloid clusters. However, during the synthesis of Au108S24(PPh3)16, the smaller gold
cluster Au6[SC(SiMe3)3]2(PPh3)4 1 could be isolated as orange crystals (figure 1), being a
possible intermediate in the formation of the multishell metalloid gold cluster Au108S24(PPh3)16.
Within 1 the six gold atoms are arranged in the form of two edge sharing tetrahedra. The Au-
Au distances inside the Au6 cluster vary from 263.7 to 282.6 pm like it is the case for the gold
[15]
atoms in the two isostructural Au6 clusters [Au6(PPh3)6][NO3]2
and
Au6[Co(CO)4]2(PPh3)4,[16] which have been described more than 30 years ago. (for a
comparison of selected distances and angles of all three clusters see the supporting information
table S1, S2)
The two SC(SiMe3)3 ligands are bound in trans position to the Au6 core with Au-S distances of
232.1 pm being slightly longer than the Au-S single bond of 228.9 pm in Ph3PAuSC(SiMe3)3.
To the remaining four gold atoms of the Au6 unit in 1, PPh3 ligands are bound with Au-P
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
distances of 228.1 and 229.6 pm, being also slightly longer compared to the Au-P distance of
226.2 pm within Ph3PAuSC(SiMe3)3.
Figure 1: Molecular structure of Au6[SC(SiMe3)3]2(PPh3)4 1 with H atoms omitted for clarity
(thermal ellipsoids with 50 % probability). Selected bond lengths [pm] and angles [°]: Au1-
Au1’ 263.82(1), Au1-Au2 282.57(1), Au1-Au3 282.21(1), Au1‘-Au2 279.69(1), Au1‘-Au3
277.26(1), Au2-Au3 263.73(1), Au1-P1 229.55(1), Au3-P2 228.11(1), Au2-S 232.11(1); Au1-
Au1‘-Au2 62.571(2), Au1-Au1‘-Au3 62.817(2), Au1-Au2-Au3 62.093(1), Au1‘-Au1-Au2
61.466(1), Au1‘-Au1-Au3 60.921(2), Au1‘-Au2-Au3 61.272(2), Au2-Au1-Au2‘ 124.037(2),
Au2-Au1-Au3‘ 96.860(2), Au3-Au1-Au2‘ 96.389(2), Au3-Au1-Au3‘ 123.739(2), P1-Au1-
Au1‘ 177.415(2), P1-Au1-Au2 116.376(1), P1-Au1-Au3 116.847(2), P2-Au3-Au1 133.619(2),
P2-Au3-Au1‘ 142.340(2), P2-Au3-Au2 153.566(2), S1-Au2-Au1 132.478(2), S1-Au2-Au1‘
149.668(2), S1-Au2-Au3 148.092(2).
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
As said before, the Au6 cluster is isostructural to the Au6 cluster Au6[Co(CO)4]2(PPh3)4 where
now Co(CO)4 substituents are bound terminally in trans position to the Au6 core, showing that
such a structural arrangement is favorable for small gold cluster compounds. As Co(CO)4 and
SC(SiMe3)3 are isolobal fragments such a similar arrangement is expected due to a similar
bonding to the terminal ligands. As 1 is obtained under the same reaction conditions as the
metalloid gold cluster Au108S24(PPh3)16, 1 might be an intermediate in the formation of the
multishell metalloid gold cluster, giving a first insight into the complicated reaction mechanism.
Interestingly, 1 and Au108S24(PPh3)16 are not coprime with respect to the gold atoms, indicating
that the Au6 cluster 1 might be an important intermediate in the formation of the metalloid gold
cluster, which has to be elucidated by future investigations.
To get further information about the influence of the ligand and the sulphur donating agent
during the synthesis of a metalloid gold cluster a variety of different compounds is needed.
With this in mind, different alterations of the compounds R3PAuCl and R3PAuSR´ (R = OPh,
n
OMe, Et, Pr; R` = C(SiMe3)3, Si(SiMe3)3) were synthesized as described in the following,
leading to a handful of yet unknown compounds that may be used as starting compounds for
further reduction studies. To obtain the anticipated products, different R3PAuCl species are
needed, whereby synthetic procedures are well known for (PhO)3PAuCl (2PhO),[17]
(MeO)3PAuCl (2MeO)
[18] and Et3PAuCl (2Et).[19] However, in the actual study, another approach
was used to synthesize these compounds, where (THT)AuCl (THT = C4H8S) was used as a
starting material, as THT is weakly coordinating to the gold atom and the synthesis itself is
comparably easily done.[20] The phosphine or phosphite ligand is then introduced, replacing the
THT ligand (equation 1).
(THT)AuCl + PR3  PR3AuCl + THT
(1)
When the reaction was finished excess phosphine or phosphite and free THT is removed in
vacuo. The reactions proceeded nearly quantitatively, so no further work-up procedure was
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
1
13
31
necessary. The purity was checked by H, C and P NMR spectroscopic measurements.
Having all the R3PAuCl compounds in hand the next step included a common salt metathesis
reaction as shown in equation 2:
R3PAuCl + LiSL  R3PAuSL + LiCl
(2)
For this reaction the two starting compounds LiSHyp (Hyp = Si(SiMe3)3) and LiSTsi (Tsi =
C(SiMe3)3) (3) had to be synthesized first. The first compound, LiSHyp, was already
synthesized and characterized by our group in 2016.[21] Compound 3 has been described by
Bonasia et al.[22] where they described that it is difficult to insert Sulphur into LiTsi like it is the
case for Selenium. Consequently, we modified the complicated procedure; i.e. the problem
getting the pure compound 3 was solved by using sulphur which was recrystallized from THF
and stored under inert conditions. Otherwise, some side species were formed, contaminating
the desired product, which inhibits the formation of pure LiSTsi. It was also important to
dissolve the sulphur in THF and conduct the reaction at -45°C so that the sulphur can insert
selectively into LiTsi. The purity of the so obtained compound 3 could be proven by NMR
spectroscopic measurements (figure S2, S3, supporting information).
Having now all starting materials in hand, the salt metathesis reactions were conducted under
slightly different reaction conditions for the different ligand systems SSi(SiMe3)3 and
SC(SiMe3)3. In case of the SSi(SiMe3)3 ligand the reactions were performed at -20° C for a
better selectivity and stability of the product and it was possible to obtain results for 2MeO, 2Et
and 2Pr. For the SC(SiMe3)3 ligand the salt metathesis reactions were performed at room
temperature and it was possible to obtain results for 2PhO, 2MeO, 2Et and 2Pr. The different
products were analyzed via X-ray crystal structure analysis, NMR spectroscopic measurements
and elemental analysis. It was also checked whether the compounds were stable in air or if they
had to be stored under inert conditions.
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
LAuSTsi – compounds [Tsi = C(SiMe3)3]:
Ph3PAuSTsi (4Ph) was already described by Bonasia et al. as mentioned before.[22] However,
although they characterized 4Ph by NMR spectroscopy and elemental analysis, no molecular
structure was experimentally determined and thus, 25 years after the first description, the
molecular structure of 4Ph is determined and shown below (Figure 2 A).
Figure 2: Molecular structure of Ph3PAuSTsi 4Ph (A), (MeO)3PAuSTsi 4MeO (B), Et3PAuSTsi
4Et (C) and nPr3PAuSTsi 4Pr (D) with H atoms omitted for clarity for clarity (thermal ellipsoids
with 50 % probability). Selected bond lengths [pm] and angles [°] are given in table 1.
4Ph crystallizes in the monoclinic space group P21/c. The backbone of 4Ph is slightly bend with
an S-Au-P angle of 174°. Compared to the Au-S distances of 217 pm in the solid state structure
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
of Au2S,[23] the Au-S distance in 4Ph (228.9) is nearly 12 pm longer. Compound 4Ph exhibits a
high stability shown by the fact that the single crystals used for X-ray crystallography were
grown by slowly evaporating technical acetone in air, leading to long crystalline colourless
blocks. 4Ph can be dissolved in standard solvents like THF, toluene, pentane and Et2O and is
stable in air for at least one month (no changes in the proton NMR spectra; see supporting
n
information figure S4). Like 4Ph, Et3PAuSTsi (4Et) and Pr3PAuSTsi (4Pr) crystallize in the
monoclinic space group P21/c. As to be seen in figure 2 all compounds are isostructural with a
slightly bent backbone with a S-Au-P angle of 178.2° for 4Et and 177.6° for 4Pr. Additionally,
the Au-S and Au-P distances are comparable, indicating that a similar bonding is present in all
compounds and the major difference is the steric demand of the R group in the phosphines. One
major difference with respect to 4Ph is that 4Et and 4Pr are not stable in air and must be stored
under inert conditions. However, similar to 4Ph, 4Et and 4Pr can be dissolved in heptane, pentane,
Et2O, THF and toluene.
Table 1: Selected bond lengths and angles of the LAu-SC(SiMe3)3 compounds shown in figure
2 and figure 3.
Au-S /pm
228.9
Au-P /pm
226.2
S-C /pm
187.5
187.8
187.2
188.7
188.2
S-Au-P /°
173.7
C-S-Au /°
110.9
4Ph
229.0
222.8
172.9
111.7
4PhO
4MeO
4Et
230.1
223.0
172.8
112.2
230.4
227.1
178.2
112.3
230.2
226.9
177.6
111.2
4Pr
Beside the phosphine adducts 4Ph, 4Et and 4Pr, (MeO)3PAuSTsi (4MeO) crystallizes in the
monoclinic space group P2/n (Figure 2), but it also isostructural to 4Ph with a slightly bend S-
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
Au-P unit (173°). Also, the Au-S distance is with 229 pm nearly equal. Nevertheless, the Au-P
distance of 4MeO (222.8 pm) is 3 pm shorter than the one for 4Ph, showing the difference of the
interactions of the phosphite group compared to the phosphine group. However, like all other
compounds 4MeO is easily dissolved in pentane, THF, toluene and Et2O.
In contrast to the other compounds presented so far [(PhO)3PAuSTsi]2 (4PhO) shows significant
differences; this means although 4PhO also crystallizes in the monoclinic space group P21/n and
is structurally comparable to 4MeO with respect to the S-Au-P angle, the Au-S and Au-P
distances (Table 1) it forms a dimeric structure in the solid state (figure 3). The Au-Au` distance
in the dimer is 311.12(7) pm, which is in the range of weak aurophilic Au-Au interactions.[24]
Compound 4PhO is not stable in air and it can be dissolved in pentane, THF, toluene and Et2O.[25]
Figure 3: Molecular structure of [(PhO)3PAuSTsi]2 4PhO with H atoms omitted for clarity
(thermal ellipsoids with 50 % probability). Selected bond lengths [pm] and angles [°]: Au–Au’
311.12(7), Au–P 223.03(6), Au–S 230.08(5), S–C 187.23(18), P–O1 158.16(14), P–O2
158.83(13), P–O3 160.74(14); S–Au–P 172.845(20), Au–P–O1 109.004(52), Au–P–O2
120.514(32), Au–P–O3 118.783(54), Au–S–C 112.233(59).
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
The comparison of selected bond lengths and angles of the Tsi ligand system (table 1) shows
some similarities and trends. While the bond lengths of the Au-S bonds and S-C bonds show
only a difference of about 1 pm and the angles of C-S-Au are nearly the same, the bond lengths
of Au-P are obviously longer for the compounds with phosphine groups as for the compounds
with the phosphite groups. It is also noteworthy that the S-Au-P unit is nearly linear for 4Et and
4Pr while it is more bent for 4Ph, 4PhO and 4MeO
.
LAuSHyp – compounds [Hyp = Si(SiMe3)3]:
Ph3PAuSHyp (5Ph) has already been described[21] and the obtained values for 5Ph are added for
comparison. All newly synthesized compounds [(MeO)3PAuSHyp (5MeO), Et3PAuSHyp (5Et)
and nPr3PAuSHyp (5Pr)] crystallize in a monoclinic crystal lattice in space group P21/c (5MeO
and 5Et) or P21/n (5Pr) and are isostructural, as to be seen in figure 4. Thereby similar S-Au-P
angles of 178.5° (5MeO), 175.3° (5Et) and 176.8° (5Pr) are realized, being thus less bent than it
is the case for 5Ph, where a S-Au-P angle of 172.3° is found. The Au-S and Au-P distances are
comparable except for 5MeO where the Au-P distance is about 3 pm shorter, being thus the
similar trend as observed for the Tsi compounds. All compounds (5Ph , 5Pr , 5Et and 5MeO) must
be stored under inert conditions and can be dissolved in heptane, pentane, Et2O, THF and
toluene.
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
Figure 4: Molecular structure of (MeO)3PAuSHyp 5MeO (A), Et3PAuSHyp 5Et (B) and
nPr3PAuSHyp 5Pr (C) with H atoms omitted for clarity (thermal ellipsoids with 50 %
probability). Selected bond lengths [pm] and angles [°] are given in table 2.
Comparing the selected bond lengths and angles of the Hyp and the Tsi ligand systems given
in table 1 and 2 shows that the Au-S bond is neither influenced by the ligand system nor by the
choice of the phosphine or phosphite donor ligand. In every case the S-Au-P angle is close to
180°. Only the Au-P bond is differing significantly by swapping from a phosphine to a
phosphite group or vice versa.
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
Table 2: Selected bond lengths and angles of the Si(SiMe3)3 ligand system.
Au-S /pm
229.2
Au-P /pm
225.9
S-Si /pm
214.8
S-Au-P /°
172.6
Si-S-Au /°
105.6
5Ph
5MeO
5Et
229.2
223.2
216.5
178.5
101.7
229.2
225.9
216.0
175.3
102.0
230.0
226.6
215.2
176.8
104.7
5Pr
A huge advantage of all of the above-mentioned compounds is the possibility to use the
31
phosphorus atom with a natural abundance of the P isotope of 100% as a probe for NMR
spectroscopy. As can be seen in table 3 the chemical shifts for the different compounds differ
remarkably, hinting to a different electronic situation at the respective phosphorous atom.
Possible reduction reactions might be easily monitored to get deeper insight into the reaction
31
mechanism. Additionally, P-NMR might be used to recognize if all the educts have reacted
and to identify the new compounds formed during the reaction. Consequently, the now
established basis of starting compounds gives on the one side the opportunity to elucidate the
influence of the different donors and substituents in the Au(I) precursor during the reduction to
31
metalloid gold clusters and also offers the possibility to monitor the reaction via P-NMR
spectroscopy.
31
Table 3: Data of the P NMR spectroscopy. All compounds were dissolved in deuterated
benzene (exception 2 Ph3P, 2 (PhO)3P, 2 (MeO)3P).
Ph3P
(PhO)3P
(MeO)3P
Et3P
nPr3P
25.10
25.99
25.43
33.20 (THF) 110.04 (CDCl3) 120.52 (CDCl3) 37.88
2
4
5
38.05
37.93
131.18
---
143.16
140.42
35.42
34.62
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
Summary and Outlook
The synthesis and characterization of Au6[SC(SiMe3)3]2(PPh3)4 1, gives a first insight into the
complicated reaction mechanism of the formation of a metalloid gold cluster via reduction of
an Au(I) precursor. For further investigations to enlighten the role of the substituent and the
ligand during the reaction a variety of different, well defined starting compounds of the
composition R3PAuSR` are described. All compounds are isostructural, and the change of the
different groups lead to changes in the electronic structure, indicating that the reactivity might
be influenced by choice. Such reduction experiments are already successfully employed for
Ph3PAuSTsi to give the metalloid gold clusters Au108S24(PPh3)16 and Au70S20(PPh3)16. Thereby,
the reduction mechanism to give the metalloid gold clusters is still unknown and the isolation
of 1 is just a first step towards a deeper understanding of the reaction mechanism. However,
applying slightly different, precisely known starting compounds might open the door to a deeper
understanding of the different factors within the complicated reaction mechanism from a
molecular precursor to a nano-scaled metalloid cluster compound. The good solubility of the
Au(I) species in different solvents also enables the option to use a one-phase as well as a two-
phase reduction protocol. In this way it may be easier to observe side products and
intermediates, formed during the reduction and/or the work up procedure, which in the end
could lead to a better understanding of the formation of metalloid gold clusters and the metal
itself. First orientating reduction reactions already lead to deeply coloured reaction solutions,
which hints to the formation of molecular metalloid gold clusters, which have to be isolated and
analysed by future ongoing investigations.
Experimental Section
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
General Considerations: All experiments were conducted in an inert gas atmosphere by using
standard Schlenk techniques. Toluene, Et2O and THF were dried with sodium and pentane was
dried with CaH2. All solvents were purified via distillation. The obtained solids were stored in
a glovebox under argon atmosphere. NMR spectroscopic measurements were done at a Bruker
DRX-250 spectrometer. The chemical shifts are given in ppm against external standards SiMe4
(1H, 13C, 29Si) and 85% phosphoric acid (31P). C6D6 was dried with 3 Å molecular sieves, CDCl3
29
was used as received without drying. For all shown Si NMR experiments the INEPT pulse
program was used. Elemental analyses were performed with a varioMICROcube in the CHNS
mode. The values of the elemental analysis may show a bigger difference compared to the pure
crystalline sample due to incomplete combustion of the compounds. HSC(SiMe3)3,[13]
(THT)AuCl,[20] (THF) LiSSi(SiMe3)3[21], Ph3PAuCl, [26] Et3P and nPr3P[27] were synthesized as
described in the literature.
Synthesis of Au6[SC(SiMe3)3]2(PPh3)4 (1): The first part of this experiment was conducted in
air. Ph3PAuCl (0.99 g, 2.0 mmol) was dissolved in 50 ml THF. Solid HSC(SiMe3)3 (0.58 g, 2.2
mmol) was added to the solution and stirred for 10 min. To the yellow solution NaBH4 (0.30 g,
8.0 mmol) dissolved in water (50 ml) was slowly added. The mixture became dark brown
immediately and lukewarm. The mixture had to stir for another 30 min and was kept static
overnight. To dissolve the black precipitate and to separate the organic and the aqueous phase
Et2O (50 ml) was added. The phases were separated, and the organic phase was dried under
vacuum to give a brown precipitate. The brown precipitate was washed with pentane (50 ml)
and afterwards extracted with toluene (50 ml), where 370 mg were dissolved. The dark brown
toluene extract was concentrated to 15 ml and layered with three times the amount of pentane
via vapor diffusion. After 4 weeks beside a thin orange film orange block like crystals of
Au6[SC(SiMe3)3]2(PPh3)4 had formed (yield 0.14 g; 0.05 mmol; 15,0 %). 1H NMR (250 MHz,
THF-d8): δ = 7.77 – 7.40 (m, PPh3), 0.21 (s, SiMe3) ppm. 13C{1H} NMR (62.9 MHz, THF-d8):
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
δ = 132.90 (d, J = 11 Hz, PPh3), 131.91 (d, J = 3 Hz, PPh3), 128.95 (d, J = 12 Hz PPh3), 2.89
(s, SiMe3) ppm. 29Si NMR (49.7 MHz, THF-d8): δ = -0.78 (decet, J = 6Hz, SiMe3) ppm. 31P{1H}
NMR (101 MHz, THF-d8): δ = 53.23 (s, Ph3PAu) ppm.
Synthesis of (MeO)3PAuCl (2MeO): (MeO)3PAuCl was synthesized as described in the
literature.[18] (MeO)3P (0.25 g, 2 mmol) was dissolved in THF (40 ml) and (THT)AuCl (0.66 g,
2 mmol) was added. The clear solution became slightly yellowish and was stirred for 1 h. All
volatiles were removed in vacuo affording a grey solid. 1H NMR (250 MHz, CDCl3): δ = 3.77
(d, J = 14 Hz, 9 H, OMe) ppm. 13C{1H} NMR (62.9 MHz, CDCl3): δ = 53.37 (s, OMe) ppm.
31P{1H} NMR (101 MHz, CDCl3): δ = 120.52 (s, (MeO)3PAuCl) ppm.
Synthesis of (PhO)3PAuCl (2PhO): (PhO)3PAuCl was synthesized similarly to (MeO)3PAuCl.
(PhO)3P (0.62 g, 2 mmol) was dissolved in THF (25 ml) and (THT)AuCl (0.66 g, 2 mmol) was
added. The clear solution became slightly yellowish and was stirred for 1 h. All volatiles were
removed in vacuo affording a grey solid. 1H NMR (250 MHz, CDCl3): δ = 7.49 – 7.19 (m, 15
H, OPh) ppm. 13C{1H} NMR (62.9 MHz, CDCl3): δ = 130.58 (d, J = 2 Hz, OPh), 126.78 (d, J
= 2 Hz, OPh), 121.25 (d, J = 6 Hz, OPh) ppm. 31P{1H} NMR (101 MHz, CDCl3): δ = 110.04
(s, (PhO)3PAuCl) ppm.
Synthesis of Et3PAuCl (2Et): Et3PAuCl was synthesized similarly to (MeO)3PAuCl. Et3P (0.24
g, 2 mmol) was dissolved in THF (30 ml) and (THT)AuCl (0.66 g, 2 mmol) was added. The
clear solution became slightly yellowish and was stirred for 1 h. All volatiles were removed in
vacuo affording a grey solid. 1H NMR (250 MHz, C6D6): δ = 1.49 (m, 6 H, Et), 0.93 (m, 9 H,
Et) ppm. 13C{1H} NMR (62.9 MHz, C6D6): δ = 18.06 (d, J = 30 Hz, Et), 9.09 (s, Et). 31P{1H}
NMR (101 MHz, C6D6): δ = 37.88 (s, Et3PAuCl) ppm.
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
n
n
n
Synthesis of Pr3PAuCl (2Pr): Pr3PAuCl was synthesized similarly to (MeO)3PAuCl. Pr3P
(0.32 g, 2 mmol) was dissolved in THF (30 ml) and (THT)AuCl (0.66 g, 2 mmol) was added.
The clear solution became slightly yellowish and was stirred for 1 h. All volatiles were removed
in vacuo affording a greasy residue. 1H NMR (250 MHz, C6D6): δ = 1.40 (m, 12 H, nPr), 0.86
(m, 9 H, nPr) ppm. 13C{1H} NMR (62.9 MHz, C6D6): δ = 28.12 (d, J = 30 Hz, nPr), 19.02 (s,
nPr), 15.82 (d, J = 15 Hz, nPr) ppm. 31P{1H} NMR (101 MHz, C6D6): δ = 25.10 (s, nPr3PAuCl)
ppm.
Synthesis of (THF)1.5LiSC(SiMe3)3 (3): (THF)1.5LiSC(SiMe3)3 was synthesized after a
modified workup procedure of the literature.[22] (THF)1.5(Et2O)0.5LiC(SiMe3)3 (23.08 g, 60
mmol) was dissolved in THF (200 ml) and the yellow solution was cooled down to -45 °C while
mixing. Sulphur was dispersed in THF (200 ml) and mixed for 30 minutes. The sulphur was
slowly decanted via cannula to the (THF)1.5(Et2O)0.5LiC(SiMe3)3 whereas the solution turned
from yellow to dark orange. The mixture was allowed to reach room temperature overnight
resulting in a yellow-orange solution. The THF was removed in vacuo leading to a yellow-
orange solid that was recrystallized in Et2O (250 ml) at -28 °C leading to pale yellow blocks of
1
the composition (THF)1.5LiSC(SiMe3)3 (yield 16.92 g; 44.7 mmol, 74.5 %). H NMR (250
MHz, C6D6): δ = 0.43 (s, 27 H, SiMe3), 3.71 – 3.66 (m, 6H, 1.5 x THF), 1.39 – 1.34 (m, 6H,
1.5 x THF) ppm. 13C{1H} NMR (62.9 MHz, C6D6): δ = 2.92 (s, SiMe3), 68.41 (s, THF), 25.12
(s, THF) ppm. 29Si NMR (49.7 MHz, C6D6): δ = -0.59 (decet, J = 6 Hz, SiMe3) ppm.
Synthesis of Ph3PAuSC(SiMe3)3 (4Ph): Ph3PAuSC(SiMe3)3 was synthesized as described in
the literature.[22] Ph3PAuCl (4.95 g, 10 mmol) was dispersed in Et2O (60 ml).
(THF)1.5LiSC(SiMe3)3 (3.79 g, 10 mmol) was dissolved in Et2O (60 ml) and decanted to
Ph3PAuCl. The cloudy white suspension became pale yellow and was stirred overnight. The
Et2O was removed and the remaining white-yellow powder was again dissolved in Et2O (80
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
ml). The extract was filtered and the pale-yellow solution was stored at -28 °C leading to
colourless needles of Ph3PAuSC(SiMe3)3 (yield 5.72 g; 7.9 mmol; 79.0%). Anal. Calc. for
C28H42AuPSSi3: C, 46.5; H, 5.8; S, 4.4%. Found: C, 47.8; H, 5.9; S, 4.8%. 1H NMR (250 MHz,
C6D6): δ = 7.44 – 7.36 (m, 6 H, PPh), 6.99 – 6.91 (m, 9 H, PPh), 0.57 (s, 27 H, SiMe3) ppm.
13C{1H} NMR (62.9 MHz, C6D6): δ = 132.41 (d, J = 14 Hz, PPh), 129.26 (d, J = 2 Hz, PPh),
127.21 (d, J = 11 Hz, PPh), 2.92 (s, SiMe3) ppm. 29Si NMR (49.7 MHz, C6D6): δ = 0.78 (decet,
J = 6 Hz, SiMe3) ppm. 31P{1H} NMR (101 MHz, C6D6): δ = 38.05 (s, Ph3PAu) ppm.
Synthesis of (MeO)3PAuSC(SiMe3)3 (4MeO): (MeO)3PAuSC(SiMe3)3 was synthesized
similarly to Ph3PAuSC(SiMe3)3. (MeO)3PAuCl (0.56 g, 1.57 mmol) was dispersed in Et2O (20
ml). (THF)1.5LiSC(SiMe3)3 (0.62 g, 1.65 mmol) was dissolved in Et2O (20 ml) and decanted to
(MeO)3PAuCl. The cloudy grey suspension became grey-green and was stirred overnight. The
Et2O was removed and the remaining grey solid was dissolved in Et2O (30 ml). The extract was
filtered and the solvent was removed again. The remaining solid was dissolved in pentane (10
ml) and the pale-yellow solution was stored at -28 °C leading to colourless blocks of
(MeO)3PAuSC(SiMe3)3 (yield 0.50 g; 0.83 mmol; 52.9%). Anal. Calc. for C13H36AuO3PSSi3:
C, 26.7; H, 6.2; S, 5.5%. Found: C, 26.9; H, 5.9; S, 3.2%. 1H NMR (250 MHz, C6D6): δ = 3.09
13
(d, J = 14 Hz, 9 H, OMe), 0.55 (s, 27 H, SiMe3) ppm. C{1H} NMR (62.9 MHz, C6D6): δ =
51.97 (s, OMe), 3.20 (s, SiMe3) ppm. 29Si NMR (49.7 MHz, C6D6): δ = 1.04 (m, SiMe3) ppm.
31P{1H} NMR (101 MHz, C6D6): δ = 143.16 (s, (MeO)3PAu) ppm.
Synthesis of [(PhO)3PAuSC(SiMe3)3]2 (4PhO): (PhO)3PAuSC(SiMe3)3 was synthesized
similarly to Ph3PAuSC(SiMe3)3. (PhO)3PAuCl (0,86 g, 1.58 mmol) was dispersed in Et2O (35
ml). (THF)1.5LiSC(SiMe3)3 (0.67 g, 1.76 mmol) was dissolved in Et2O (40 ml) and decanted to
(PhO)3PAuCl. The cloudy white suspension became yellowish and was stirred overnight.
Afterwards, Et2O was removed and the remaining grey solid was dissolved in Et2O (50 ml).
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
The extract was filtered and the solvent was removed again. The remaining solid was dissolved
in pentane (20 ml) and the pale-yellow solution was stored at 4 °C leading to colourless blocks
of [(PhO)3PAuSC(SiMe3)3]2 (yield 0.32 g; 0.41 mmol; 25.6%). Anal. Calc. for
C56H84Au2O6P2S2Si6: C, 43.6; H, 5.5; S, 4.2%. Found: C, 43.8; H, 5.6; S, 4.0%. 1H NMR (250
MHz, C6D6): δ = 7.13 – 7.07 (m, 6 H, OPh), 6.99 – 6.92 (m, 6 H, OPh), 6.87 – 6.80 (m, 3H,
OPh), 0.33 (s, 27 H, SiMe3) ppm. 13C{1H} NMR (62.9 MHz, C6D6): δ = 150.11 (d, J = 4 Hz,
OPh), 130.45 (s, OPh), 126.31 (s, OPh), 121.38 (d, J = 5 Hz, OPh), 2.97 (s, SiMe3) ppm. 29Si
31
NMR (49.7 MHz, C6D6): δ = 0.97 (decet, J = 6 Hz, SiMe3) ppm. P{1H} NMR (101 MHz,
C6D6): δ = 131.18 (s, (PhO)3PAu) ppm.
Synthesis of Et3PAuSC(SiMe3)3 (4Et): Et3PAuSC(SiMe3)3 was synthesized similarly to
Ph3PAuSC(SiMe3)3. Et3PAuCl (0,35 g, 1 mmol) was dispersed in Et2O (20 ml).
(THF)1.5LiSC(SiMe3)3 (0.38 g, 1 mmol) was dissolved in Et2O (20 ml) and decanted to
Et3PAuCl. The cloudy grey suspension became yellowish and was stirred overnight. The Et2O
was removed and the remaining grey solid was dissolved in Et2O (30 ml). The extract was
filtered and the solvent was removed again. The remaining solid was dissolved in heptane (10
ml) and the pale-yellow solution was stored at -28 °C leading to colourless plates of
Et3PAuSC(SiMe3)3 (yield 0.33 g; 0.57 mmol; 57.0%). Anal. Calc. for C16H42AuPSSi3: C, 33.2;
H, 7.3; S, 5.5%. Found: C, 33.2; H, 9.1; S, 5.5%. 1H NMR (250 MHz, C6D6): δ = 1.03 (m, 6
13
H, Et), 0.71 (m, 9 H, Et), 0.57 (s, 27 H, SiMe3) ppm. C{1H} NMR (62.9 MHz, C6D6): δ =
29
18.17 (d, J = 30 Hz, Et), 8.61 (s, Et) 3.32 (s, SiMe3) ppm. Si NMR (49.7 MHz, C6D6): δ =
0.98 – 0.07 (m, SiMe3) ppm. 31P{1H} NMR (101 MHz, C6D6): δ = 35.42 (s, Et3PAu) ppm.
n
n
Synthesis of Pr3PAuSC(SiMe3)3 (4Pr): Pr3PAuSC(SiMe3)3 was synthesized similarly to
n
Ph3PAuSC(SiMe3)3. Pr3PAuCl (0.39 g, 1 mmol) was dispersed in Et2O (20 ml).
(THF)1.5LiSC(SiMe3)3 (0.38 g, 1 mmol) was dissolved in Et2O (10 ml) and decanted to
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
nPr3PAuCl. The cloudy white suspension stayed white and was stirred overnight. The Et2O was
removed and the remaining grey solid was dissolved in pentane (25 ml). The extract was filtered
n
and the clear solution was stored at 4 °C leading to colourless blocks of Pr3PAuSC(SiMe3)3
(yield 0.44 g; 0.71 mmol; 71.0%). Anal. Calc. for C19H48AuPSSi3: C, 36.8; H, 7.8; S, 5.2%.
Found: C, 38.4; H, 6.9; S, 4.7%. 1H NMR (250 MHz, C6D6): δ = 1.31 – 1.04 (m, 12 H, nPr),
0.78 (t, J = 7 Hz, 9 H, nPr), 0.57 (s, 27 H, SiMe3) ppm. 13C{1H} NMR (62.9 MHz, C6D6): δ =
n
n
n
29
28.41 (d, J = 30 Hz, Pr), 18.79 (s, Pr), 15.78 (d, J = 15 Hz, Pr), 3.28 (s, SiMe3) ppm. Si
31
NMR (49.7 MHz, C6D6): δ = 0.55 (decet, J = 6 Hz, SiMe3) ppm. P{1H} NMR (101 MHz,
C6D6): δ = 25.99 (s, nPr3PAu) ppm.
Synthesis of (MeO)3PAuSSi(SiMe3)3 (5MeO): (MeO)3PAuSSi(SiMe3)3 was synthesized
similarly to Ph3PAuSC(SiMe3)3. (MeO)3PAuCl (036 g, 1 mmol) was dissolved in Toluene (15
ml) and cooled down to -20 °C. (THF)2LiSSi(SiMe3)3 (0.43 g, 1 mmol) was dissolved in
Toluene (10 ml) and decanted to (MeO)3PAuCl. Upon reaching room temperature the solution
changed its colour from pale yellow to red orange. The Toluene was removed and the remaining
solid was dissolved in pentane (20 ml). The extract was filtered, concentrated to 10 ml and the
solution was stored at -28 °C for one week leading to colourless crystals of
(MeO)3PAuSSi(SiMe3)3 (yield 0.24 g; 0.4 mmol; 40.0%). Anal. Calc. for C12H36AuO3PSSi4:
C, 24.0; H, 6.0; S, 5.3%. Found: C, 23.8; H, 6.1; S, 6.4%. 1H NMR (250 MHz, C6D6): δ = 3.09
13
(d, J = 14 Hz, 9 H, OMe), 0.50 (s, 27 H, SiMe3) ppm. C{1H} NMR (62.9 MHz, C6D6): δ =
51.95 (s, OMe), 0.68 (s, SiMe3) ppm. 29Si NMR (49.7 MHz, C6D6): δ = -13.04 (decet, J = 6 Hz,
SiMe3), -57.20 (s, Si(SiMe3)3) ppm. 31P{1H} NMR (101 MHz, C6D6): δ = 140.42 (s,
(MeO)3PAu) ppm.
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
Synthesis of Et3PAuSSi(SiMe3)3 (5Et): Et3PAuSSi(SiMe3)3 was synthesized similarly to
Ph3PAuSC(SiMe3)3. Et3PAuCl (0.55 g, 1 mmol) was dissolved in Toluene (20 ml) and cooled
down to -20 °C. (THF)2LiSSi(SiMe3)3 (0.43 g, 2 mmol) was dissolved in Toluene (15 ml) and
decanted to Et3PAuCl. Upon reaching room temperature the solution changed its colour from
pale yellow to red orange. The Toluene was removed and the remaining solid was dissolved in
Et2O (20 ml). The extract was filtered and the solvent was removed again. The remaining solid
was dissolved in heptane (10 ml) and the colourless solution was stored at -28 °C leading to
colourless crystals of Et3PAuSSi(SiMe3)3 (yield 0.20 g; 0.33 mmol; 33.0%). Anal. Calc. for
C15H42AuPSSi4: C, 30.3; H, 7.2; S, 5.4%. Found: C, 30.6; H, 7.2; S, 5.5%. 1H NMR (250 MHz,
C6D6): δ = 1.08 (m, 6 H, Et), 0.70 (m, 9 H, Et), 0.49 (s, 27 H, SiMe3 ) ppm. 13C{1H} NMR (62.9
29
MHz, C6D6): δ = 18.12 (d, J = 30 Hz, Et), 8.56 (s, Et) 0.77 (s, SiMe3) ppm. Si NMR (49.7
31
MHz, C6D6): δ = 13.43 (decet, J = 6 Hz, SiMe3), -57.61 (s, Si(SiMe3)3) ppm. P{1H} NMR
(101 MHz, C6D6): δ = 34.62 (s, Et3PAu) ppm.
n
n
Synthesis of Pr3PAuSSi(SiMe3)3 (5Pr): Pr3PAuSSi(SiMe3)3 was synthesized similarly to
Ph3PAuSC(SiMe3)3. nPr3PAuCl (0.39 g, 1 mmol) was dissolved in Toluene (15 ml) and cooled
down to -20 °C. (THF)2LiSSi(SiMe3)3 (0.43 g, 1 mmol) was dissolved in Toluene (10 ml) and
decanted to nPr3PAuCl. Upon reaching room temperature the solution remained colourless. The
Toluene was removed and the remaining solid was dissolved in heptane (20 ml). The extract
was filtered and the solution was stored at -28 °C for five days leading to colourless crystals of
nPr3PAuSSi(SiMe3)3 (yield 0.37 g; 0.58 mmol; 58.0 %). Anal. Calc. for C18H48AuPSSi4: C,
1
33.9; H, 7.5; S, 5.0%. Found: C, 33.3; H, 7.6; S, 5.2%. H NMR (250 MHz, C6D6): δ = 1.17
n
n
13
(m, 12 H, Pr), 0.78 (t, J = 7 Hz, 9 H, Pr), 0.51 (s, 27 H, SiMe3) ppm. C{1H} NMR (62.9
n
n
n
MHz, C6D6): δ = 28.37 (d, J = 30 Hz, Pr), 18.73 (s, Pr), 15.77 (d, J = 15 Hz, Pr), 0.74 (s,
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
29
SiMe3) ppm. Si NMR (49.7 MHz, C6D6): δ = -13.36 (decet, J = 6 Hz, SiMe3), -57.73 (s,
Si(SiMe3)3) ppm. 31P{1H} NMR (101 MHz, C6D6): δ = 25.43 (s, nPr3PAu) ppm.
X-Ray Structural Characterization. Crystals were mounted on the diffractometer at 150 K.
The data were collected on a Bruker APEX II DUO diffractometer equipped with an IμS
microfocus sealed tube and QUAZAR optics for monochromated MoKα radiation (λ = 0.71073
Å) and equipped with an Oxford Cryosystems cryostat. A semiempirical absorption correction
was applied using the program SADABS. The structure was solved by direct methods and
refined against F2 for all observed reflections. Programs used: SHELXS and SHELXL[28] within
the Olex2 program package.[29] In case of 1, only one co crystallized toluene molecule could be
refined properly. One more solvent accessible void (173 A³) is identified and modelled with the
SQUEEZE routine of the PLATON program,[30] containing only 13 electrons. This fits to a
toluene occupation of 25%. Additionally, a second orientation of 1 (2 %) is present in the
crystal, which could be refined for the cluster core, but not for the ligands. Furthermore, due to
the presence of SiMe3 groups, compounds 4Ph, 4OPh and 4Et show a classic umbrella disorder,
which could be refined with a disorder model. In case of compound 5Et, 4 crystallographic
independent molecules could be found in the asymmetrical unit and one of them shows a
disorder in the PEt3 part, which could also be refined with a disorder model. In case of 4MeO
two molecules are present in the asymmetric unit where in one case the OMe groups are
disordered which could be refined by a disorder model.
1 * 2 toluene
C106H130Au6P4S2Si6
2942.43
4Ph * acetone
C31H48AuOPSSi3
780.96
4MeO
Formula
C13H36AuO3PSSi3
584.68
Formula weight
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
T /K
150.0
180.01
monoclinic
P21/c
150.0
Crystal system
Space group
a /Å
triclinic
P-1
monoclinic
P2/n
12.7730(5)
14.5686(6)
16.5831(7)
74.341(2)
70.937(2)
77.053(2)
2776.9(2)
1
8.9221(3)
13.8504(4)
28.7583(9)
90
13.3453(9)
12.4929(8)
28.668(2)
90
b /Å
c /Å
α /°
β /°
95.608(2)
90
100.1590(10)
90
γ /°
V /Å3
3536.79(19)
4
4704.7(5)
8
Z
µ /mm-1
ρ /g∙cm-3
Reflns. meas.
Independent reflns.
R(int.)
8.098
4.387
6.571
1.760
1.467
1.651
65976
80234
51182
14699
8501
14352
0.0376
1.049
0.0343
1.049
0.0417
1.019
GooF
R1 (I > 2σ)
wR2 (all data)
CCDC number
0.0235
0.0518
1503108
0.0181
0.0419
1841825
0.0312
0.0631
1841820
(4PhO
)
4Et
4Pr
2
Formula
C56H84Au2O6P2S2Si6
1541.76
C16H42AuPSSi3
578.76
C19H48AuPSSi3
620.84
Formula weight
T /K
150.0
150.0
150.02
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
Crystal system
Space group
a /Å
monoclinic
P21/n
monoclinic
P21/c
monoclinic
P21/n
12.1564(3)
24.9179(7)
21.8939(5)
90
12.3335(7)
29.9253(16)
13.5782(8)
90
14.5105(5)
13.6741(5)
15.5744(6)
90
b /Å
c /Å
α /°
β /°
90.0080(10)
90
91.5600(10)
90
112.001(2)
90
γ /°
V /Å3
6631.9(3)
4
5009.6(5)
8
2865.20(19)
4
Z
µ /mm-1
ρ /g∙cm-3
Reflns. meas.
Independent reflns.
R(int.)
4.683
6.161
5.392
1.544
1.535
1.439
134680
31250
101739
12959
222726
13522
0.0293
1.014
0.0625
1.032
0.0450
1.147
GooF
R1 (I > 2σ)
wR2 (all data)
CCDC number
0.0255
0.0573
1841821
0.0278
0.0524
1841823
0.0216
0.0478
1841827
5MeO
5Et
5 Pr
Formula
C12H36AuO3PSSi4
600.76
C15H42AuPSSi4
594.84
C18H48AuPSSi4
636.92
Formula weight
T /K
150.0
150.01
150.0
Crystal system
monoclinic
monoclinic
monoclinic
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
Space group
a /Å
P21/c
P21/c
P21/n
15.1647(9)
8.6620(5)
19.3969(12)
90
17.7003(15)
18.9602(16)
32.938(3)
90
14.7402(8)
14.3037(7)
15.5747(8)
90
b /Å
c /Å
α /°
β /°
96.6940(10)
90
92.6740(10)
90
112.127(2)
90
γ /°
V /Å3
2530.5(3)
4
11042.0(16)
16
3041.9(3)
4
Z
µ /mm-1
ρ /g∙cm-3
Reflns. meas.
Independent reflns.
R(int.)
6.155
5.634
5.118
1.577
1.431
1.391
19182
213428
33823
37782
7768
6218
0.0256
1.005
0.0938
0.997
0.0783
1.041
GooF
R1 (I > 2σ)
wR2 (all data)
CCDC number
0.0262
0.0592
1841819
0.0401
0.0751
1841822
0.0335
0.0848
1841826
Acknowledgements
We thank Dr. Claudio Schrenk for helpful discussion and Wolfgang Bock for performing the
elemental analysis.
References
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
[1] J. Weyer, Chem. Unserer Zeit 1989, 23, 16-23.
[2] A. Schnepf, Structure and Bonding, Clusters – Contemporary Insight in Structure and
Bonding (Ed. S. Dehnen), 2017, 174, 135-200.
[3] M. W. Heaven, A. Dass, P. S. White, K. M. Holt, R. W. Murray, J. Am. Chem. Soc. 2008,
130, 3754-3755.
[4] Z. Gan, J. Chen, J. Wang, C. Wang, M.-B. Li, C. Yao, S. Zhuang, A. Xu, L. Li, Z. Wu,
Nat. Commun. 2017, 8, 14739.
[5] P. D. Jadzinsky, G. Calero, C. J. Ackerson, D. A. Bushnell, R. D. Kornberg, Science 2007,
318, 430-433.
[6] C. Zeng, Y. Chen, K. Kirschbaum, K. J. Lambright, R. Jin, Science 2016, 354, 1580-1584.
[7] N. A. Sakthivel, S. Theivendran, V. Ganeshraj, A. G. Oliver, A. Dass, J. Am. Chem. Soc.
2017, 139, 15450-15459.
[8] C. Zeng, Y. Chen, C. Liu, K. Nobusada, N. L. Rosi, R. Jin, Sci. Adv. 2015, 1:e1500425.
[9] C. Zeng, C. Liu, Y. Chen, N. L. Rosi, R. Jin, J. Am. Chem. Soc. 2016, 138, 8710-8713.
[10] M. Brust, M. Walker, D. Bethell, D. J. Schiffrin, R. Whyman, J. Chem. Soc. Chem.
Commun. 1994, 801-802.
[11] A. Uehara, S. G. Booth, S. Y. Chang, S. L. M. Schroeder, T. Imai, T. Hashimoto, J. F. W.
Mosselmans, R. A. W. Dryfe, J. Am. Chem. Soc. 2015, 137, 15135 – 15144.
[12] S. G. Booth, A. Uehara, S. Y. Chang, C. La Fontaine, T. Fuji, Y. Okamoto, T. Imai, S. L.
M. Schroeder, R. A. W. Dryfe, Chem. Sci. 2017, 8, 7954 – 7962.
[13] S. Kenzler, C. Schrenk, A. Schnepf, Angew. Chem. Int. Ed. 2017, 56, 393-396; Angew.
Chem. 2017, 129, 402-406.
[14] S. Kenzler, C. Schrenk, A. R. Frojd, H. Häkkinen, A. Z. Clayborne, A. Schnepf, Chem.
Commun. 2018, 54, 248-251.
[15] J. W. A. van der Velden, J. J. Bour, W. P. Bosman, J. H. Noordik, Inorg. Chem. 1983, 22,
1913-1918.
[16] C. E. Briant, K. P Hall, D. M. P. Mingos, A. C. Wheeler, J. Chem. Soc. Dalton Trans.
1986, 687-692.
[17] K. Speck, K. Karaghiosof f, T. Magauer, Org. Lett. 2015, 17, 1982-1985.
[18] C. E. Strasser, S. Cronje, H. Schmidbauer, H. G. Raubenheimer, J. Organomet. Chem.
2006, 691, 4788-4796.
[19] J. Wang, X. Mi, J. Wang, Y. Yang, Green. Chem. 2017, 19, 634-637.
[20] H. Yang, Y. Wang, J. Yan, X. Chen, X. Zhang, H. Häkkinen, N. Zheng, ChemCatChem
2014, 136, 7197-7200.
This article is protected by copyright. All rights reserved.

10.1002/ejic.201800595
European Journal of Inorganic Chemistry
[21] M. Kotsch, C. Gienger, C. Schrenk, A. Schnepf, Z. Anorg. Allg. Chem. 2016, 642, 670-
675.
[22] P. J. Bonasia, D. E. Gindelberger, J. Arnold, Inorg. Chem. 1993, 32, 5126-5131.
[23] K. Ishikawa, T. Isonaga, S. Wakita, Y. Suzuki, Solid State Ion. 1995, 79, 60-66.
[24] The van der Waals radius for Au is about 166 pm indicating that there are interactions
between two gold atoms up to 330 pm. H. Schmidbaur, A. Schier, Chem. Soc. Rev. 2008, 37,
1931-1951.
[25] During the synthesis of 4PhO a side product with the molecular formula (THF)3LiAu(STsi)2
4side was obtained, where the phosphite group P(OPh)3 is substituted by another LiSC(SiMe3)3
group to give the corresponding ate complex 4side (molecular structure is given in the supporting
information figure S5). In case of the other Au(I) complexes 4MeO, 4Et and 4Pr such a side
product is not observed.
[26] Y. Xu, X. Hu, S. Zhang, X. Xi, Y. Wu, ChemCatChem 2016, 8, 262-267.
[27] W. Wolfsberger, H. Schmidbauer, Syn. React. Inorg. Metal-org. Chem. 1974, 4, 149-156.
[28]
(a) G. M. Sheldrick, Acta Crystallogr. 2008, A64, 112−122. (b) G. M. Sheldrick, Acta
Crystallogr., Sect. C: Struct. Chem. 2015, C71, 3−8.
[29]
O. V. Dolomanov, L. J. Bourhis, R. J. Gildea, J. A. K. Howard, H. Puschmann, J. Appl.
Crystallogr. 2009, 42, 339−341.
[30] A. L. Spek, J. Appl. Cryst. 2003, 36, 7-13.
This article is protected by copyright. All rights reserved.