Helmstedt et al.
was added quickly. After decolorization (a few seconds) of the
yellow solution, a solution of 4-mercaptobenzoic acid (0.15 g, 1.00
mmol) in ethanol (25 mL) was added, and a light yellow solid
immediately precipitated. After 5 min of stirring at room temper-
ature, the solid [Au(SC6H4-4-COOH)] was filtered off, washed three
times with water and ethanol, and dried under vacuum. All these
steps can be carried out in air without any precautions regarding
exclusion of oxygen or water. Yield: 0.32 g (91%). Anal. Calcd
for C7H5O2SAu (350.1): C, 24.01; H, 1.44. Found: C, 23.37; H,
1.38. IR (KBr pellet; ν˜ (cm-1)): 2972 m, 2649 m, 2524 m, 2074 w,
1796 w (br), 1687 s (br), 1589 s, 1561 s, 1485 m, 1415 s, 1395 s
(sh), 1301 m (br), 1272 s (br), 1228 s (br), 1173 s, 1124 m, 1105 m,
1078 m, 1043 m, 1012 s, 933 w (br), 868 w, 846 m, 790 m (sh),
758 s, 702 w, 682 m, 629 w, 545 m (br), 519 m (br), 476 m (sh),
430 w, 417 w, 404 w.
therefore suitable for selective coordination of each functional
group to only one metal center.10 Because of the lability of
the rhodium-phosphine bond and the nucleophilicity of the
nonbonding electron pairs at sulfur, macrocyclic structures
were obtained.11
We now show that replacement of rhodium(I) by gold(I),
which prefers linear coordination and forms more stable
metal-phosphorus bonds, restricts the nuclearity of the
resulting complex to three. The trinuclear heterometallic
complex [Cp*2Zr{κ1O-OOCC6H4-4-SAu(PMe2Ph)}{κ2O,O′-
OOCC6H4-4-SAu(PMe2Ph)}] (3) is stable in solution and is
therefore more suitable than the rhodium(I) complex for
investigation of its spectroscopic properties.
Experimental Section
PMe2Ph (0.12 mL, 0.92 mmol) was added to a suspension of
[Au(SC6H4-4-COOH)] in thf (20 mL). Within a few minutes the
solid dissolved yielding a pale yellow solution. All volatile
compounds were evaporated in vacuum, and the resulting pale
yellow solid was washed with n-hexane and recrystallized from
thf to afford bright yellow needles. Yield: 0.42 g (93%). Mp
(decomp) 193 °C. Anal. Calcd for C15H16O2SPAu (488.27): C,
36.90; H, 3.30. Found: C, 36.46; H, 3.33. IR (KBr pellet; ν˜ (cm-1)):
3440 m (br), 3053 w, 2963 m, 2906 w, 2664 w, 2550 w, 1689 s
(sh), 1588 s, 1548 w, 1486 w, 1435 m, 1416 m (sh), 1313 m,
1290 m, 1261 s, 1224 w, 1177 m, 1089 s (br, sh), 1022 s (br),
952 w, 914 m, 867 w, 803 s (sh), 756 w, 743 m, 720 w, 694 m,
549 w, 525 w, 481 m (sh), 446 w. UV/vis (thf), λmax (nm): 330. EI
MS, m/z, rel. Int.: 488 [Au(SC6H4-4-COOH)(PMe2Ph)], 1%;
368 [Me2PhPAuS]+, 1%; 335 [Me2PhPAu]+, 1%; 154
[HSC6H4COOH]+, 17%; 138 [PhMe2P]+, 100%; 123 [PhMeP]+,
General Details. Operations were performed under a dry nitrogen
atmosphere using standard Schlenk techniques, except where
otherwise stated. Solvents and reagents were purified by standard
procedures. H2mba was purchased from Aldrich and used without
further purification. PMe2Ph12 and [Cp*2ZrMe2]13 (Cp* ) C5Me5)
were prepared according to literature procedures. NMR spectra
were recorded with a Bruker AVANCE DRX 400 (1H NMR
400.13 MHz, 13C NMR 100.3 MHz, 31P NMR 161.97 MHz)
1
(Scheme 1). Si(CH3)4 was used as internal standard for the H
and 13C NMR spectra. H3PO4 was used as external standard for
the 31P NMR spectra. IR spectra (KBr) were recorded on a Perkin-
Elmer Spektrum 2000 FTIR spectrometer in the range 350-4000
cm-1. The elemental composition was determined with a Hereaus
CHN-O-S-Analyzer. Melting points were determined in sealed
capillaries (under nitrogen) using a Gallenkamp apparatus and are
uncorrected. UV/vis spectra were recorded with a Perkin-Elmer
Lambda 900 UV/vis/NIR spectrometer. Photoluminescence (PL)
experiments were performed with a Spex Fluorolog-3 spectrometer.
Crystals of 1 were dispersed in a viscous polyfluoroether oil
(ABCR), layered between two 1 mm thick quartz plates and
mounted on a coldfinger of an optical closed-cycle cryostat
(Leybold) operating at 15-293 K. All emission spectra were
corrected for the wavelength-dependent response of the spectrom-
eter. The PL quantum yield of 1 in the solid state was evaluated
according to a procedure described elsewhere.14
1
92%; 107 [PhP-H]+, 17%; 77 [Ph]+, 22%. H NMR ([D8]thf, 25
°C): δ 1.89 (d, 6H, 2JHP ) 12.0 Hz, P(CH3)2), 7.47 (d, 2H, 3JHH
)
3
8.3 Hz, H4), 7.50 (m, 3H, H7, H9), 7.62 (d, 2H, JHH ) 8.3 Hz,
H3), 7.85 (m, 2H, H8), ca. 11.3 (broad, COOH). 13C{1H} NMR
1
([D8]thf, 25 °C): δ 14.9 (d, JCP ) 35.8 Hz, P(CH3)2), 125.6 (s,
C5), 129.5 (s, C3), 129.7 (d, 2JCP ) 11.2 Hz, C7), 132.0 (d, 4JCP
)
3
2.3 Hz, C9), 132.2 (s, C4), 132.6 (d, JCP ) 13.4 Hz, C8), 134.0
(d, 1JCP ) 55.8 Hz, C6), 153.2 (s, C2), 167.6 (s, C1). 31P{1H} NMR
([D8]thf, 25 °C): δ 10.0 (s, PMe2Ph).
[Cp*2Zr(K1O-O2CC6H4-4-SH)(K2O,O′-O2CC6H4-4-SH)](2).4-Mer-
captobenzoic acid (0.18 mg, 1.2 mmol) was dissolved in thf (15
mL) and added to a solution of [Cp*2ZrMe2] (0.24 g, 0.6 mmol) in
toluene (8 mL). Over the next ten minutes evolution of gas was
observed, and the solution was stirred for 1 h at room temperature.
The solution was concentrated to 2 mL, and the product precipitated
with n-hexane (5 mL). Yield: 0.37 g (83%). Mp: 269 °C (decomp).
Anal. Calcd for C34H40O4S2Zr (740.1): C, 61.7; H, 6.5. Found: C,
61.2; H, 6.4. IR (KBr pellets, ν˜ (cm-1)): 3062 m, 2957 s, 2905 s,
2726 w, 2488 m, 2033 w, 1920 w, 1802 w, 1687 w, 1618 s (sh
1635 s), 1594 s, 1580 s, 1559 m, 1518 s, 1498 s, 1446 s, 1397 m,
1379 s, 1363 m, 1330 s (sh 1325 s), 1279 w, 1260 m, 1238 w,
1176 m, 1140 s, 1098 s, 1016 s, 956 w, 915 w, 872 s, 845 s, 805 s,
763 s, 734 m, 717 w, 689 m, 631 w, 612 w, 593 w, 542 s, 516 s,
471 m. FAB MS, m/z, rel. int.: 531 [Cp*Zr(OOCC6H4S)2]+, 100%;
513 [Cp*2Zr(OOCC6H4S)]+, 82%; 395 [Cp*2ZrOO + H]+, 18%;
377 [Cp*2ZrO + H]+, 17%. 1H NMR (C6D6, 25 °C): δ 1.86 (s, 30
Scheme 1. Numbering Scheme for the Assignment of the NMR
Signals of the Aromatic Rings
[Au(SC6H4-4-COOH)(PMe2Ph)] (1). H[AuCl4]·3H2O (0.39 g,
1.00 mmol) was dissolved in distilled water (5 mL). A solution of
S(CH2CH2OH)2 (0.24 g, 2.00 mmol) in distilled water (10 mL)
(10) Helmstedt, U.; Lo¨nnecke, P.; Hey-Hawkins, E. Inorg. Chem. 2006,
45, 10300–10308.
(11) Helmstedt, U.; Lo¨nnecke, P.; Reinhold, J.; Hey-Hawkins, E. Eur.
J. Inorg. Chem. 2006, 4922–4930.
(12) Meisenheimer, J.; Casper, J.; Ho¨ring, M.; Lauter, W.; Lichtenstadt,
L.; Samuel, W. Liebigs Ann. Chem. 1926, 449, 213–248.
(13) (a) Manriquez, J. M.; Bercaw, J. E. J. Am. Chem. Soc. 1974, 96, 6229–
6230. (b) Manriquez, J. M.; McAllister, D. R.; Rosenberg, E.; Shiller,
A. M.; Williamson, K. L.; Chan, S. I.; Bercaw, J. E. J. Am. Chem.
Soc. 1978, 100, 3078–3083. (c) Manriquez, J. M.; McAllister, D. R.;
Sanner, R. D.; Bercaw, J. E. J. Am. Chem. Soc. 1978, 100, 2716–
2724.
3
H, C5(CH3)5), 3.08 (s, 2H, SH), 7.07 (d, 4H, JHH ) 8.0 Hz, H4),
8.35 (d, 4H, 3JHH ) 8.0 Hz, H3). 13C{1H} NMR (C6D6, 25 °C): δ
11.9 (s, C5(CH3)5), 122.9 (s, C4, C5(CH3)5), 131.4 (s, C3), 132.7
(s, C5), 137.9 (s, C2), 174.1 (s, C1).
(14) Lebedkin, S.; Langetepe, T.; Sevillano, P.; Fenske, D.; Kappes, M. M.
J. Phys. Chem. B 2002, 106, 9019–9026.
5816 Inorganic Chemistry, Vol. 47, No. 13, 2008