Synthesis and coordination chemistry of gold(I) acetylides. The solid-state structure of {[η2-(Ph3P)AuC≡CFc]Cu(μ-Cl)}2

Article abstract of DOI:10.1021/om010183d

The gold(I) acetylide (Ph₃P)AuC≡CC₆H₃ (CH₂NMe₂)_2-3,5 (3) is accessible by the reaction of (Ph₃P)AuCl (1) with HC≡CC₆H₃(CH₂NMe₂)_2-

Full text of DOI:10.1021/om010183d

1968
Organometallics 2001, 20, 1968-1972
Syn th esis a n d Coor d in a tion Ch em istr y of Gold (I)
Acetylid es. Th e Solid -Sta te Str u ctu r e of
{[η2-(P h 3P )Au CtCF c]Cu (µ-Cl)}2
Heinrich Lang,*,† Stefan Ko¨cher,† Stephan Back,† Gerd Rheinwald,† and
Gerard van Koten‡
Fakulta¨t fu¨r Naturwissenschaften, Institut fu¨r Chemie, Lehrstuhl Anorganische Chemie,
Technische Universita¨t Chemnitz, Strasse der Nationen 62, D-09111 Chemnitz, Germany, and
Debye Institute, Department of Metal-Mediated Synthesis, Utrecht University, Padualaan 8,
3584 CH Utrecht, The Netherlands
Received March 7, 2001
The gold(I) acetylide (Ph3P)AuCtCC6H3(CH2NMe2)2-3,5 (3) is accessible by the reaction
of (Ph3P)AuCl (1) with HCtCC6H3(CH2NMe2)2-3,5 (2) in a 1:1 molar ratio. Base-catalyzed
desilylation of (Ph3P)AuCtCSiMe3 (4) produces the homobimetallic gold(I) species (Ph3P)-
AuCtCAu(PPh3) (5). However, the intermediate formation of (Ph3P)AuCtCH could not be
evidenced, but is most likely. The coordination chemistry of 5 and (Ph3P)AuCtCFc (6) toward
different copper(I) halides [CuX]n (7a , X ) Cl; 7b, X ) Br) is presented. While heterodinuclear
6 affords with equimolar amounts of 7a hexanuclear {[η2-(Ph3P)AuCtCFc]Cu(µ-Cl)}2 (8),
homobinuclear 5 produces with 7b in a 1:1 molar ratio via ligand exchange polymeric [Cu-
CtC]n (10) and mononuclear (Ph3P)AuBr (11). A feasible reaction mechanism for the
formation of the latter species is presented. The solid-state structure of 8 is reported. It
exhibits a linear array around the gold(I) center and a coplanar arrangement of the Cu2Cl2
and the gold(I) acetylide entities.
In tr od u ction
(NLO) properties also the liquid crystalline behavior of
gold(I) acetylides is of interest.9,16
In the search for new material properties a manifold
of different organometallic complexes were prepared.1
In this context, the chemical and physical properties of
gold(I) acetylides have recently been the subject of
thorough studies.2-15 Besides their nonlinear optical
Moreover, mixed-metal gold(I) acetylides containing
a late transition metal (TM) complex fragment, such as
Fc or {Pt} (Fc ) (η5-C5H4)Fe(η5-C5H5); {Pt} ) Pt-
[C6H3(CH2NMe2)2-2,6]), were prepared.17 The study of
their electrochemical behavior revealed that a remotely
* Corresponding author. E-mail: heinrich.lang@chemie.tu-chem-
nitz.de. Fax: +49-371-531 1833.
(4) (a) J ohnson, A.; Puddephatt, R. J . J . Chem. Soc., Dalton Trans.
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Treurnicht, I. Can. J . Chem. 1988, 66, 3167. (c) J ia, G.; Puddephatt,
R. J .; Vittal, J . J .; Payne, N. C. Organometallics 1993, 12, 263. (d) J ia,
G.; Puddephatt, R. J .; Scott, J . D.; Vittal, J . J . Organometallics 1993,
12, 3565. (e) J ia, G.; Payne, N. C.; Vittal, J . J .; Puddephatt, R. J .
Organometallics 1993, 12, 4771. (f) Payne, N. C.; Ramachandran, R.;
Puddephatt, R. J . Can. J . Chem. 1995, 73, 6. (g) Irwin, M. J .; J ia, G.;
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Vicente, J .; Chicote, M. T.; Abrisqueta, M. D.; J ones, P. G. Organo-
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† Technische Universita¨t Chemnitz.
‡ Debye Institute, Utrecht University.
(1) For example see: (a) Marder, S. R. In Inorganic Materials; Bruce,
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10.1021/om010183d CCC: $20.00 © 2001 American Chemical Society
Publication on Web 04/20/2001

Synthesis of Gold(I) Acetylides
Organometallics, Vol. 20, No. 10, 2001 1969
present late TM center, e.g., Fe(II), shifts the Au(I)/Au(0)
reduction potential to a more negative value.17
As shown by Vicente et al., complex 4 can easily be
prepared by the reaction of (PPh3)AuCl (1) with HCtC-
SiMe3 in diethylamine as solvent.5c However, it ap-
peared that in the synthesis of 3 the reaction of 1 with
HCtC[C6H3(CH2NMe2)2-3,5] (2) in Et2NH as solvent
requires the addition of catalytic amounts of [CuCl]n to
obtain 3 in high yields. The latter procedure was first
published by Bruce and co-workers.3c
A variety of TM monoacetylides have been studied
with respect to their ability to form σ,η2-complexes.18
Prominent representative species have been prepared
with, for example, Re(CO)5 end groups.19 Also, Pt(II)
σ-acetylide-containing coordination polymers were re-
ported.20 Moreover, η2-acetylene complexes of copper(I)
salts are of interest due to their applicability in the
deposition of thin copper films for electronic devices, e.g.,
by using chemical vapor deposition techniques (CVD).21
In view of our earlier studies in this area18c,22 we set
out to study the synthesis of mono- as well as homo-
and heterobimetallic gold(I) acetylides of the general
type (Ph3P)AuCtCR (R ) singly bonded organic or
organometallic group) and their coordination behavior
toward copper(I) halides.
Resu lts a n d Discu ssion
Syn th esis a n d Sp ectr oscop y. In the course of our
studies toward the synthesis and reaction chemistry of
gold(I) acetylides we choose as starting material the
gold(I) acetylide (Ph3P)AuCtCR [3, R ) C6H3(CH2-
NMe2)2-3,5; 4, R ) SiMe3;5c 6, R ) Fc; Fc ) (η5-C5H4)-
Fe(η5-C5H5)17].
The IR spectrum of 3 reveals the stretching frequency
of the CtC triple bond at 2112 cm-1, in a region that is
typical for this type of molecules.2-15
The same is true for the 1H NMR spectrum of 3,
showing resonance signals due to the respective organic
groups present.17,22 However, it must be noted that in
the 13C{1H} NMR spectrum of 3 only one resonance
signal for the CtC carbon atoms was found at 103.5
ppm. The phenomenon of low detectability of the sp-
hybridized carbon atoms of gold(I) acetylides has al-
ready been described earlier.3
(9) (a) Whittall, I. R.; Humphrey, M. G.; Houbrechts, S.; Persoons,
A.; Hockless, D. C. R. Organometallics 1996, 15, 5738. (b) Naulty, R.
H.; Cifuentes, M. P.; Humphrey. M. G.; Houbrechts, S.; Boutton, C.;
Persoons, A.; Heath, G. A.; Hockless, D. C. R.; Luther-Davies, B.;
Samoc, M. J . Chem. Soc., Dalton Trans. 1997, 4167. (c) Whittall, I. R.;
Humphrey, M. G.; Samoc, M.; Luther-Davies, B.; Hockless, D. C. R. J .
Organomet. Chem. 1997, 544, 189. (d) Whittall, I. R.; Humphrey, M.
G.; Houbrechts, S.; Maes, J .; Persoons, A.; Schmid, S.; Hockless, D. C.
R. J . Organomet. Chem. 1997, 544, 277. (e) Whittall, I. R.; Humphrey,
M. G.; Samoc, M.; Luther-Davies, B. Angew. Chem., Int. Ed. Engl.
1997, 36, 370. (f) Whittall, I. R.; McDonagh, A. M.; Humphrey, M. G.;
Samoc, M. Adv. Organomet. Chem. 1998, 43, 349.
(10) (a) Coates, G. E.; Parkin, C. J . Chem. Soc. 1962, 1787. (b)
Coates, G. E.; Parkin, C. J . Chem. Soc., Chem. Commun. 1962, 1787.
(c) Carriedo, G. A.; Riera, V.; Solans, X.; Solans, J . Acta Crystallogr. C
1988, 44, 979.
(11) (a) Yam, V. W. W.; Choi, S. W. K.; Cheung, K. K. J . Chem. Soc.,
Dalton Trans. 1996, 3411. (b) Yam, V. W. W.; Choi, S. W. K.; Cheung,
K. K. Organometallics 1996, 15, 1734. (c) Yam, V. W. W.; Choi, S. W.
K. J . Chem. Soc., Dalton Trans. 1996, 4227. (d) Yau, J .; Mingos, D. M.
P. J . Chem. Soc., Dalton Trans. 1997, 1103.
A suitable tool to monitor the successful formation of
3 is given by 31P{1H} NMR spectroscopy. While the 31P
resonance signal for (Ph3P)AuCl (1) is found at 33.8
ppm,22 the phosphorus signal of 3 is low-field shifted
by approximately 10 ppm to 43.6 ppm.
The FAB mass spectrum of 3 shows the peak of the
respective molecular ion M+ at the expected m/z value
(675). Further fragments are M+ - NMe2 (m/z ) 631)
and M+ - 2 NMe2 (m/z ) 587). As base peak AuPPh3
(m/z 459) is found.
+
To desilylate the Me3SiCtC entity in (PPh3)Au-
CtCSiMe3 (4)5c to obtain (Ph3P)AuCtCH, this complex
was treated with a methanolic K2CO3 solution at 25 °C.
However, instead of mononuclear (Ph3P)AuCtCH,5c the
homodinuclear gold(I) complex (Ph3P)AuCtCAu(PPh3)
(5)6b was formed in quantitative yield (Scheme 1), which
probably is caused by the application of the basic
desilylation procedure.
(12) Mathews, J . A.; Watters, L. L. J . Am. Chem. Soc. 1900, 22, 108.
(13) Mitchell, C. M.; Stone, F. G. A. J . Chem. Soc., Dalton Trans.
1972, 102.
(14) Werner, H.; Otto, H.; Tri Ngo Khac; Burschka, C. J . Organomet.
Chem. 1984, 262, 123.
(15) (a) Nast, R.; Kirner. U. Z. Anorg. Allg. Chem. 1964, 330, 311.
(b) Nast, R. Angew. Chem. 1965, 77, 352. (c) Nast. R.; Schneller. P.;
Hengefeld, A. J . Organomet. Chem. 1981, 214, 273.
(16) Nalwa, H. Appl. Organomet. Chem. 1991, 5, 349.
(17) Back, S.; Gossage, R. A.; Lang, H., van Koten, G. Eur. J . Inorg.
Chem. 2000, 1457.
(18) (a) Bruce, M. I.; Clark, R.; Howard, J .; Woodward, P. J .
Organomet. Chem. 1972, 42, C107. (b) Olbrich, F.; Behrens, U.; Weiss,
E. J . Organomet. Chem. 1994, 472, 365. (c) Lang, H.; Ko¨hler, K.; Blau,
S. Coord. Chem. Rev. 1995, 143, 113, and literature cited therein. (d)
Ipaktschki, J .; Mirzaei, F.; Mu¨ller, B. G.; Beck, J .; Serafin, M. J .
Organomet. Chem. 1996, 526, 363.
Sch em e 1. F or m a tion of 5 by Tr ea tm en t of 4 w ith
K2CO3/MeOH
(19) (a) Mihan, S.; Weidmann, T.; Weinrich, V.; Fenske, D.; Beck,
W. J . Organomet. Chem. 1997, 541, 423. (b) Mihan, S.; Su¨nkel, K. H.;
Beck, W. Personal communication. (c) Stepnicka, P.; Gyepes, R.;
Cisarova, I.; Varga, V.; Polasek, M.; Horacek, M.; Mach, K. Organo-
metallics 1999, 18, 627.
(20) (a) Yamazaki, S.; Deeming, A. J . J . Chem. Soc., Dalton Trans.
1993, 3051. (b) Fornie´s, J .; Lalinde, E.; Mart´ın, A.; Moreno, M. T. J .
Organomet. Chem. 1995, 490, 179.
(21) For example see: (a) J ain, A.; Chi, K. M.; Kodas, T. T.;
Hampden-Smith, M. J .; Farr, J . D.; Paffett, M. F. Chem. Mater 1991,
3, 995. (b) Shin, H. K.; Chi, K. M.; Farkas, J .; Hampden-Smith, M. J .;
Kodas, T. T.; Duesler, E. N. Inorg. Chem. 1992, 31, 424. (c) Lang, H.;
Ko¨hler, K.; Zsolnai, L. Chem. Ber. 1995, 128, 519.
(22) Back, S.; Gossage, R. A.; Lutz, M.; del R´ıo, I.; Spek, A. L.; Lang,
H.; van Koten, G. Organometallics 2000, 19, 3296.
Presumably in the reaction of 4 with K2CO3/MeOH
as intermediate [(Ph3P)AuCtC]- is formed, which,
however, reacts with further 4 under ligand substitution

1970 Organometallics, Vol. 20, No. 10, 2001
Lang et al.
Sch em e 2. P r ep a r a tion of 10 a n d 11 via
to 5. The direct synthesis of a similar species was
described by Cross et al. using a NaOEt/EtOH solution
containing (Ph3P)AuCl (1) and acetylene gas. The
analytical and spectroscopic data of 5 are consistent
with the reported values.3b
In ter m ed ia te F or m a tion of 9
Complexes (PPh3)AuCtCR [3, R ) C6H3(CH2NMe2)2-
3,5; 4, R ) SiMe3;5c 6, R ) Fc; Fc ) (η5-C5H4)Fe(η5-
C5H5)17] as well as (PPh3)AuCtCAu(PPh3) (5) contain
a CtC unit, which allows the preparation of oligo-
nuclear TM species. As an example, the homo- and
heterobimetallic complexes 5 and 6 were reacted with
copper(I) halides in an attempt to synthesize Cu2(µ-X)2-
bridged oligonuclear complexes. The copper(I) salts
[CuX]n (7a , X ) Cl; 7b, X ) Br) were chosen because of
their well-studied reaction chemistry toward CtC triple
bonds.18c,23 For example, η2-alkyne complexes of general
type [(η2-RCtCR)Cu(µ-X)]2 (R ) Me3Si, ...; X ) Cl, Br,
CO2R, ...) are of fundamental interest, since these
species can successfully be applied as organometallic
precursors for growing thin copper films on different
substrates by applying the chemical vapor deposition
process.21,23
In the case of (Ph3P)AuCtCFc (6), reaction with
1/n[CuCl]n in a 1:1 molar ratio in dichloromethane as
solvent affords the hexanuclear complex 8 in 70% yield.
To obtain another hexanuclear species, (Ph3P)Au-
CtC-Au(PPh3) (5) was reacted with equimolar amounts
of 1/n[CuBr]n (7b) in dichloromethane at 25 °C. How-
ever, in the course of the reaction the colorless reaction
mixture developed an intense red color and a red
precipitate was formed. After appropriate workup, the
red precipitate could be identified by its spectroscopic
data as polymeric [CuCtC]n (10).24 As a further product,
(Ph3P)AuBr (11) could be characterized by 31P{1H} NMR
spectroscopic studies and by X-ray crystallography.25
An explanation for the formation of 10 and 11 in the
reaction of 5 with 7b is given by the assumption of the
formation of the heterobimetallic intermediate 9 (Scheme
2).
The hexanuclear intermediate 9 provides the pos-
sibility for an intramolecular ligand exchange, which
finally yields polymeric 10 and mononuclear 11. A
similar observation was made when {Pt}CtCSiMe3
({Pt} is the bis(orthoamino)aryl unit Pt[C6H3(Me2-
NCH2)2-2,6]) was reacted with copper(I) halides, yielding
{Pt}Cl along with [CuCtCSiMe3]n; that is, in this
reaction the Pt-C bond rather than the C-Si bond is
selectively broken.22 However, this behavior contrasts
with that of (CO)5ReCtCRe(CO)5.19
Solid -Sta te Str u ctu r e of {[η2-(P h 3P )Au CtCF c]-
Cu (µ-Cl)}2 (8). Single crystals of 8 could be obtained
by diffusion-controlled crystallization of a n-pentane
solution into a dichloromethane solution containing 8
at 25 °C. The solid-state structure of 8 is depicted in
Figure 1. Important structural details are given in Table
1, and crystal and intensity collection data are sum-
marized in Table 2 (Experimental Section).
Solid orange 8, which is stable to air for several days,
is poorly soluble in unpolar organic solvents, but dis-
solves readily in, for example, dichloromethane and
tetrahydrofuran. However, in dichloromethane solutions
it starts to decompose after several days, even under
inert gas atmosphere.
The IR spectrum of 8 exhibits the expected absorption
band for the CtC triple bond at 1924 cm-1. Compared
to the starting material 6, it is shifted by almost 190
cm-1 to lower wavenumbers, which is typical for the η2-
coordination of a CtC building block to a TM complex
fragment such as CuCl17 and hence the formation of 8.
1H as well as 13C{1H} NMR spectroscopic studies on
8 do not reveal significant changes in the chemical shifts
of the organic groups present, when compared to 6.17
For the Fc entities a singlet at 4.22 ppm and two pseudo-
triplets at 4.11 and 4.44 ppm with a coupling constant
of J HH ) 3.6 Hz are found.
Hexanuclear 8 crystallizes in the triclinic space group
P1h with one molecule per unit cell. Molecules of 8 exhibit
a center of inversion; all symmetry-generated atoms are
marked with the suffix a. The best planes through the
atoms Cu(1)-C(1)-C(2) and through the Cu2(µ-Cl)2
entity, Cu(1)-Cl(1)-Cl(1a)-Cu(1a), are tilted by only
1.22°. Thus, the coordination sphere around Cu(1) is
(23) (a) Guy, R. G.; Shaw, B. L. Adv. Inorg. Chem. Radiochem. 1962,
4, 77. (b) Aleksandrov, G. G.; Gol’ding, I. R.; Sterlin, S. R.; Sladkov, A.
M.; Struchkov, Yu. T.; Garbuzova, I. A.; Aleksanyan, V. T. Izv. Akad.
Nauk. SSSR, Ser. Khim. 1980, 29, 2679. (c) Maier, G.; Hoppe, M.;
Reisenauer, H. P.; Kru¨ger, C. Angew. Chem., Int. Ed. Engl. 1982, 21,
437; Angew. Chem. Suppl. 1982, 1861. (d) Pasquali, M.; Leoni, P.;
Floriani, L.; Gaetani-Manfredotti, A. Inorg. Chem. 1982, 21, 4324. (e)
Aalten, H. L.; van Koten, G.; Riethorst, E.; Stam, C. H. Inorg. Chem.
1989, 28, 4140. (f) Reger, O. L.; Huff, M. F. Organometallics 1990, 9,
2807. (g) Olbrich, F.; Behrens, U.; Gro¨ger, G.; Weiss, E. J . Organomet.
Chem. 1993, 448, C10.
(24) Sladkov, A. M.; Gol’ding, I. R. Russ. Chem. Rev. 1979, 48, 868.
(25) Barron, P. F.; Engelhardt, L. H.; Healy, P. C.; Oddy, J .; White,
A. N. Aust. J . Chem. 1987, 40, 1545.

Synthesis of Gold(I) Acetylides
Organometallics, Vol. 20, No. 10, 2001 1971
Ta ble 2. Cr ysta l a n d In ten sity Collection Da ta for
8
empirical formula
chemical formula
fw
C31H26AuCl3CuFeP
60H48Au2Cl2Cu2Fe2P2, 2 CH2Cl2
852.19
C
cryst syst
space group
a (Å)
b (Å)
c (Å)
triclinic
P1h
10.4288(1)
11.6962(1)
14.3504(2)
67.6206(5)
82.2386(6)
64.5716(7)
2889.6(11)
1.937
R (deg)
â (deg)
γ (deg)
V (Å3)
F
calc (g cm-3
)
F(000)
824
Z
1
cryst dimens (mm)
diffractometer model
radiation (λ, Å)
0.4 × 0.2 × 0.1
Bruker Smart CCD
0.71073
0.350855, 0.138235
6.569
173(2)
ω-scan
max., min. transmn
abs coeff (µ, mm-1
temperature (K)
scan mode
)
F igu r e 1. ZORTEP drawing (50% probability level) and
atom-numbering scheme of 8.
scan range (deg)
index ranges
1.54 e θ e 30.45
-8 e h e 14
-14 e k e 16
-19 e l e 19
11 535
Ta ble 1. Selected Dista n ces (Å) a n d An gles (d eg)
for 8a ,b
total no. of reflns
no. of unique reflns
bond lengths
angles
7643
Au(1)-P(1) 2.2804(16) P(1)-Au(1)-C(1)
176.90(19)
176.3(5)
162.4(6)
35.4(2)
94.03(6)
85.97(6)
Au(1)-C(1)
C(1)-C(2)
C(2)-C(3)
C(1)-Cu(1)
C(2)-Cu(1)
Cu(1)-Cl(1)
2.020(6)
1.227(9)
1.438(9)
2.014(6)
2.205(6)
2.2711(17)
Au(1)-C(1)-C(2)
344
C(1)-C(2)-C(3)
C(1)-Cu(1)-C(2)
Cl(1a)-Cu(1)-Cl(1)
Cu(1a)-Cl(1)-Cu(1)
Cu(1)-Cl(1a) 2.3107(18)
Cl(1)-Cu(1a) 2.3107(18)
;
)
)
D(1)-Fe(1)c
D(2)-Fe(1)c
1.6475(29)
1.6513(31)
2
a
Symmetry transformations used to generate equivalent at-
b
oms: 1 - x, -y + 1, -z + 2. Standard deviations are given as
the last significant figure in parentheses. c D(1), D(2): centroids
of the cyclopentadienyl ligands.
trigonal-planar and comprises the η2-bonded acetylide
and the µ-bridging chloro ligands. A similar feature has
been observed for other Cu2(µ-X)2-containing complexes
(X ) halide), e.g., [(η2-Me3SiCtCSiMe3)2Cu2(µ-Br)2],23a
[(η2-PhCtCSiMe3)Cu(µ-Br)]2,26 or [(η2-FpCtCPh)Cu(µ-
Cl)]2 [Fp ) (η5-C5H5)Fe(CO)2]18a or the copper(I) tmtch
complexes prepared by Weiss and Behrens (tmtch )
3,3,6,6-tetramethyl-1-thia-4-cycloheptyne).27 The CtC
triple bond distance C(1)-C(2) amounts to 1.227(9) Å
and lies in the range of bond lengths encountered in
related η2-bonded organic or organometallic alkynes to
copper(I) salts; for example, in [(η2-FpCtCPh)Cu(µ-Cl)]2
the CtC bond length is 1.27(2) Å.18a Compared to
known CtC bond lengths reported for other gold(I)
acetylides,3-15 the η2-coordination of copper(I) does not
cause a significant change of the CtC distance. The
Au(1)-P(1) bond [2.2804(16) Å] resembles values re-
ported for this bond in other organo gold(I) phosphorus
complexes, e.g., (Ph3P)AuCtCC6H4NO2-4 [2.277(1) Å].9a
The Au(1)-C(1) distance of 2.020(6) Å is slightly longer
than found, for example, in complex 5 [1.988(6) Å]3b or
(nmdpp)AuCtCPh [2.00(2) Å] [nmdpp ) (neomenthyl)-
(26) Back, S.; Stein, T.; Lang, H. Acta Crystallogr. Sect. C 2000,
submitted.
(27) Gro¨ger, G.; Olbrich, F.; Weiss, E.; Behrens, U. J . Organomet.
Chem. 1996, 514, 81.

1972 Organometallics, Vol. 20, No. 10, 2001
Lang et al.
FAB mass spectra were recorded on a Finnigan 8400 mass
spectrometer operating in the positive-ion mode. Melting
points were determined using sealed nitrogen-purged capil-
68.7 (iC/C5H4), 70.0 (C5H5), 71.9 (CH/C5H4), 129.1 (d, J PC
)
i
11.3 Hz, CH/C6H5), 129.9 (d, J PC ) 62.7 Hz, C/C6H5), 131.5
(CH/C6H5), 134.3 (d, J PC ) 13.8 Hz, CH/C6H5).a Anal. Calcd
laries on
a
Gallenkamp MFB 595 010 M melting point
for C60H48Au2Cl2Cu2Fe2P2 (1534.57): C, 46.96; H, 3.15.
apparatus. Microanalyses were performed by H. Kolbe, Mu¨l-
heim/Ruhr.
Found: C, 47.15; H, 3.36. aSignals for the CtC entity were
not detected.
Gen er a l Rem a r k s. (Ph3P)AuCl (1),3c C6H3(CH2NMe2)2-3,5-
(CtCH)-1,28 (Ph3P)AuCtCSiMe3,5c and (Ph3P)AuCtCFc (6)17
were prepared by published procedures. All other chemicals
were purchased from commercial sources and were used as
received.
X-r a y Str u ctu r e Deter m in a tion . The structure of 8 was
determined by single-crystal X-ray diffraction. The preparation
of single crystals was done in perfluoro alkyl ether from ABCR
GmbH & Co KG (viscosity 1600 cSt). Data were collected on a
Bruker Smart CCD diffractometer using Mo KR radiation. The
unit cell was determined with the program SMART.29 For data
integration and refinement of the unit cell the program
SAINT29 was used. The space group was determined using the
program or ABSEN,30 and the empirical absorption correction
was done with SADABS.31 In the structure solution by direct
methods the program SIR9732 was employed, and the structure
refinement was based on least-squares methods based on F2
with SHELX97.33 The plots of the molecular structures were
visualized using the program ZORTEP.34 All non-hydrogen
atoms were fully refined in their located positions; the
hydrogen atoms were positioned as riding models to their
neighboring atom and refined depending on their position.
Crystallographic data of 8 are given in Table 2.
4. Rea ction of 5 w ith 7b. To 5 (200 mg, 0.2 mmol)
dissolved in 30 mL of dichloromethane was added 60 mg of
7b (0.4 mmol). After 5 min a red precipitate was formed, which
subsequently was identified by its IR spectrum as [CuCtC]n
(10)24 (isolated yield: 30 mg, 90% based on 5). After 1 h of
stirring at 25 °C, all volatiles were evaporated in an oil-pump
vacuum, and the residue was extracted with dichloromethane
(3 × 10 mL). The combined dichloromethane extracts were
evaporated (oil-pump vacuum) to yield colorless 11 (230 mg,
90% based on 5).
1. Syn th esis of (P h 3P )Au [CtC-1-C6H3(CH2NMe2)2-3,5]
(3). At 25 °C 1/n[CuCl]n (7a ) (20 mg, 0.02 mmol) was added in
one portion to a stirring mixture of 1 (480 mg, 1 mmol),
C6H3(CH2NMe2)2-3,5-(CtCH)-1 (2) (270 mg, 1.25 mmol), and
30 mL of HNEt2. After 4 h of stirring, all volatiles were
removed in an oil-pump vacuum. The residue was suspended
in H2O (15 mL), and the suspension was extracted with
dichloromethane (3 × 10 mL). The combined dichloromethane
extracts were dried over Na2SO4 and then filtered off. After
drying in an oil-pump vacuum, 3 (610 mg, 0.9 mmol, 85%
relative to 1) could be obtained as a colorless solid. Mp: [°C]
1
148. IR (KBr): [cm-1] 2112 [νCtC]. H NMR (CDCl3): [δ] 2.18
(s, 12 H, NMe2), 3.41 (s, 4 H, CH2), 7.09 (s, 2 H, C6H3), 7.10 (s,
1 H, C6H3), 7.3-7.7 (m, 15 H, Ph). 13C{1H} NMR (CDCl3): [δ]
43.9 (NMe2), 62.7 (CH2), 103.5 (AuCtC), 127.6 (d, J PC ) 50
Hz, iC/C6H5), 127.7 (d, J PC ) 11 Hz, CH/C6H5), 128.9 (iC/
C6H3CtC), 130.1 (CH/C6H3), 130.1 (CH/C6H5), 130.6 (CH/
C6H3), 132.9 (d, J PC ) 15 Hz, CH/C6H5), 137.2 (iC/C6H3CH2-
NMe2).a 31P{1H} NMR (CDCl3): [δ] 43.6 (PPh3). FAB MS [m/z
(rel intensity)]: 675 (40) [M]+, 631 (30) [M - NMe2]+, 587 (50)
[M - 2NMe2]+, 459 (100) [AuPPh3]+. Anal. Calcd for C32H34
-
AuN2P (674.61): C, 56.97; H, 5.08. Found: C, 56.51; H, 5.01.
aThe second signal for the CtC entity could not be assigned
unequivocally.
(Ph3P)AuBr (11) was identified by FAB-MS and X-ray
crystallography.25
2. Syn th esis of (P h 3P )Au CtCAu (P P h 3) (5) by th e
Rea ction of (P h 3P )Au CtCSiMe3 w ith MeOH/K2CO3. At
25 °C, 400 mg of (Ph3P)AuCtCSiMe3 (0.7 mmol) was dissolved
in 20 mL of methanol, and 0.5 g of K2CO3 (3.3 mmol) was
added in one portion. After 10 h of stirring at this temperature
all volatiles were evaporated. Then, the residue was extracted
with dichloromethane (4 × 5 mL). The combined dichlo-
romethane extracts were concentrated to 5 mL, and 30 mL of
n-pentane was added. After decantation of the supernatant
solution and drying of the residue in an oil-pump vacuum, 5
(220 mg, 65% based on (Ph3P)AuCtCSiMe3) could be isolated
as a colorless solid.
Ack n ow led gm en t. The authors are grateful to the
Deutsche Forschungsgemeinschaft and the Fonds der
Chemischen Industrie for financial support.
Su p p or tin g In for m a tion Ava ila ble: Tables containing
final atomic coordinates for non-hydrogen atoms and equiva-
lent isotopic temperature displacement parameters, a complete
list of bond lengths and angles, and anisotropic displacement
parameters for 8 have been deposited as a CIF file. This
material is available free of charge via the Internet at
http://pubs.acs.org.
The spectroscopic data of 5 are in agreement with the data
reported for this homobimetallic complex.3b
3. Syn th esis of {[η2-(P h 3P )Au CtCF c]Cu (µ-Cl)}2 (8). At
25 °C, 40 mg of 1/n[CuCl]n (7a ) (0.4 mmol) was added to 6
(130 mg, 0.2 mmol) dissolved in 30 mL of dichloromethane.
After 3 h of stirring, all volatiles were evaporated in an oil-
pump vacuum, and the residue was extracted with dichlo-
romethane (3 × 10 mL). The combined dichloromethane
extracts were evaporated to yield orange 8 (110 mg, 0.07 mmol,
70% based on 6). Mp: [°C] 145. IR (KBr): [cm-1] 1924 [νCtC].
1H NMR (CDCl3): [δ] 4.11 (pt, J HH ) 3.6 Hz, 4 H, C5H4), 4.22
(s, 10 H, C5H5), 4.44 (pt, J HH ) 3.6 Hz, 4 H, C5H4), 7.4-7.6
(m, 30 H, C6H5). 13C{1H} NMR (CDCl3): [δ] 67.8 (CH/C5H4),
OM010183D
(29) SAINT; Bruker AXS Inc.: Madison, WI, 1998.
(30) McArdle, P. J . Appl. Crystallogr. 1996, 29, 306.
(31) Sheldrick, G. M. SADABS V2.01, Program for Empirical
Absorption Correction of Area Detector Data; University of Go¨ttin-
gen: Germany, 2000.
(32) Altomare, A.; Burla, M. C.; Camalli, M.; Cascarano, G. L.;
Giacovazzo, C.; Guagliardi, A.; Moliterni, A. G. G.; Polidori, G.; Spagna,
R. J . Appl. Crystallogr. 1999, 32, 115.
(33) Sheldrick, G. M. SHELX97, Programs for Crystal Structure
Analysis (Release 97-2); University of Go¨ttingen: Germany, 1997.
(34) Zsolnai, L.; Huttner, G. ZORTEP; University of Heidelberg:
Germany, 1994.
(28) Steenwinkel, P.; J ames, L. S.; Grove, D. M.; Veldman, N.; Spek,
A. L.; van Koten, G. Chem. Eur. J . 1996, 2, 1440.