New neutral and anionic alkynylgold(I) complexes via new synthetic methods. Crystal and molecular structures of [Au(C≡CSiMe3)(CNtBu)], and [Au(C≡CR)PR′3] (R′ = cyclohexyl, R = CH2Cl, CH2Br; R′ = Ph, R = SiMe3, tBu)

Article abstract of DOI:10.1021/om970725k

[(PPh₃)₂N][Au(acac)₂] (acac = acetylacetonate) reacts with terminal alkynes RC≡CH to give [(PPH₃)₂N][Au(C≡CR)₂] (R = H, ^tBu, SiMe₃, CH₂X (X = Cl, Br, OH)) complexes. The reactions between [(PPh₃)₂N][Au(C≡CH)₂] and [(PPh₃)₂N][AuX2] (X = Cl, Br, I) give [(PPh₃)₂N][Au(C≡CH)X] complexes. Neutral mononuclear [Au(C≡CR)(NHEt₂)] (R = SiMe₃, ^tBu), [Au(C≡CR)(PR′₃)] (R = H, R′ = Ph, C₆H₄OMe-4; R = CH₂Cl, CH₂Br, CH₂OH, R′ = Cy = cyclohexyl; R = SiMe₃, R′ = Ph, C₆H₄OMe-4, Cy; R = ^tBu, R′ = Ph, Cy, C₆H₄OMe-4), [Au(C≡CR)(CN^tBu)] (R = SiMe₃, ^tBu), and [Au(C≡CR){C(NH^tBu)(NEt₂)}] (R = H, SiMe₃, ^tBu) or dinuclear [(AuL)₂{μ-C≡C(CH₂)₅C≡C)] (L = PPh₃, CN^tBu, C(NH^tBu)(NEt₂)) are obtained via a variety of synthetic methods: (i) reaction between [(PPh₃)₂N][Au(C≡CH)₂] and [Au(PR₃)₂]ClO₄, (ii) reaction of terminal alkynes with [Au(acac)(L)], (iii) reaction of [AuClL] complexes with terminal alkynes in diethylamine, (iv) substitution reactions (e.g., [Au(C≡CR)(NHEt₂)] + PR′₃), (v) reaction of diethylamine with alkynyl isocyanide derivatives to give alkynylcarbene complexes. The crystal structures of [(PPh₃)₂N][Au(C≡CCH₂OH)₂], [Au(C≡CSiMe₃)(CN^tBu)], and [Au(C≡CR)(PR′₃)] (R′ = Cy, R = CH₂Cl, CH₂Br; R′ = Ph, R = SiMe₃, ^tBu) were determined.

Full text of DOI:10.1021/om970725k

5628
Organometallics 1997, 16, 5628-5636
New Neu tr a l a n d An ion ic Alk yn ylgold (I) Com p lexes via
New Syn th etic Meth od s. Cr ysta l a n d Molecu la r
Str u ctu r es of [(P P h 3)2N][Au (CtCCH2OH)2],
[Au (CtCSiMe3)(CNtBu )], a n d [Au (CtCR)P R′3] (R′ )
t
Cycloh exyl, R ) CH2Cl, CH2Br ; R′ ) P h , R ) SiMe3, Bu )†
J ose´ Vicente,*,‡ Mar´ıa-Teresa Chicote,* and Mar´ıa-Dolores Abrisqueta
§
Grupo de Quı´mica Organometa´lica, Departamento de Qu´ımica Inorga´nica, Universidad de
Murcia, Aptdo. 4021, Murcia, 30071 Spain
Peter G. J ones*,|
Institut fu¨r Anorganische und Analytische Chemie, Technische Universita¨t Braunschweig,
Postfach 3329, 38023 Braunschweig, Germany
Received August 14, 1997X
[(PPh3)2N][Au(acac)2] (acac ) acetylacetonate) reacts with terminal alkynes RCtCH to
t
give [(PPh3)2N][Au(CtCR)2] (R ) H, Bu, SiMe3, CH2X (X ) Cl, Br, OH)) complexes. The
reactions between [(PPh3)2N][Au(CtCH)2] and [(PPh3)2N][AuX2] (X ) Cl, Br, I) give
[(PPh3)2N][Au(CtCH)X] complexes. Neutral mononuclear [Au(CtCR)(NHEt2)] (R ) SiMe3,
tBu), [Au(CtCR)(PR′3)] (R ) H, R′ ) Ph, C6H4OMe-4; R ) CH2Cl, CH2Br, CH2OH, R′ ) Cy
t
) cyclohexyl; R ) SiMe3, R′ ) Ph, C6H4OMe-4, Cy; R ) Bu, R′ ) Ph, Cy, C6H4OMe-4),
t
[Au(CtCR)(CNtBu)] (R ) SiMe3, Bu), and [Au(CtCR){C(NHtBu)(NEt2)}] (R ) H, SiMe3,
tBu) or dinuclear [(AuL)2{µ-CtC(CH2)5CtC}] (L ) PPh3, CNtBu, C(NHtBu)(NEt2)) are
obtained via a variety of synthetic methods: (i) reaction between [(PPh3)2N][Au(CtCH)2]
and [Au(PR3)2]ClO4, (ii) reaction of terminal alkynes with [Au(acac)(L)], (iii) reaction of
[AuClL] complexes with terminal alkynes in diethylamine, (iv) substitution reactions (e.g.,
[Au(CtCR)(NHEt2)] + PR′3), (v) reaction of diethylamine with alkynyl isocyanide derivatives
to give alkynylcarbene complexes. The crystal structures of [(PPh3)2N][Au(CtCCH2OH)2],
[Au(CtCSiMe3)(CNtBu)], and [Au(CtCR)(PR′3)] (R′ ) Cy, R ) CH2Cl, CH2Br; R′ ) Ph, R )
t
SiMe3, Bu) were determined.
In tr od u ction
Although a few of the reported alkynylgold(I) com-
plexes are anionic or cationic,2,9-19 most of them are
neutral and the majority correspond to the type [Au-
The preference of gold(I) for a linear coordination
geometry, together with the linearity of the CtC bond
in alkynyl ligands, make alkynylgold(I) complexes at-
tractive candidates for the design of linear-chain metal-
containing polymers with extended backbone electronic
conjugation. The expectation that these electronically
flexible rigid-rod polymers might exhibit interesting
properties either difficult or impossible to achieve with
conventional organic polymers justifies the rapidly
growing interest in alkynylgold(I) complexes. Among
the many alkynylgold(I) complexes described, some
show liquid-crystalline properties1,2 or nonlinear-optical
behavior.3 In addition, some alkynylgold(I) derivatives
belong to a new class of luminophores with interesting
photophysical and photochemical properties.4-8
t
(CtCR)(L)] (R ) Ph, Bu, CF3, C6H10OH; L ) tertiary
phosphine)13,20-26 or [Au2(µ-CtC)L2] (L ) phosphines
or L2 ) diphosphines).4-7,10,27-31 The few gold(I) com-
(5) Yam, V. W.-W.; Choi, S. W.-K.; Cheung, K.-K. J . Chem. Soc.,
Dalton Trans. 1996, 3411.
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L159.
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Trans. 1993, 2929.
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13, 887.
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Nauk SSSR. Ser. Khim. 1984, 956.
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1787.
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Chem., Int. Ed. Engl. 1995, 34, 1894.
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Soc., Chem. Commun. 1988, 212.
† Dedicated to Professor Pascual Royo on the occasion of his 60th
birthday.
‡ E-mail: jvs@fcu.um.es.
§ WWW: http://www.scc.um.es/gi/gqo/.
| E-mail: jones@xray36.anchem.nat.tu-bs.de.
X Abstract published in Advance ACS Abstracts, November 15, 1997.
(1) Alejos, P.; Coco, S.; Espinet, P. New J . Chem. 1995, 19, 799.
(2) Irwin, M. J .; Gia, G.; Payne, N. C.; Puddephatt, R. J . Organo-
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S0276-7333(97)00725-5 CCC: $14.00 © 1997 American Chemical Society

Neutral and Anionic Alkynylgold(I) Complexes
Organometallics, Vol. 16, No. 26, 1997 5629
obtained by reacting [(PPh3)2N)[Au(acac)2] (acac ) acetylac-
etonate) (0.1-0.3 mmol) with an excess of the corresponding
alkyne (molar ratio ca. 1:40) in dichloromethane; for the
synthesis of 1, a saturated solution of acetylene in degassed
dichloromethane (20 mL) was used and bubbling of acetylene
was continued during the reaction. After 30 min of stirring,
the reaction mixtures were filtered through Celite, the solu-
tions concentrated under vacuum (to ca. 5 mL), and diethyl
ether (20 mL) added to precipitate white solids, which were
recrystallized from dichloromethane/diethyl ether. 1: Yield
91%. Mp: 225 °C. Anal. Calcd for C40H32AuNP2: C, 61.15;
H, 4.10; N, 1.80. Found: C, 60.57; H, 4.34; N, 1.92. ΛM (Ω-1
cm2 mol-1): 108. IR (cm-1): ν(CH), 3266 (vw); ν(CtC), 1962
(w). 1H NMR: δ 1.37 (s, 2H, CH) 13C{1H} NMR: δ 87.10 (s,
CH), 127.02 (s, CAu). 2: Yield 95%. Mp: 181 °C. Anal. Calcd
for C48H48AuNP2: C, 64.21; H, 5.39; N, 1.56. Found: C, 64.32;
H, 5.47; N, 1.58. ΛM (Ω-1 cm2 mol-1): 85. IR (cm-1): ν(CtC),
plexes with other alkynyl groups include two ethynyl
(R ) H) complexes9,32,33 as well as some derivatives with
R ) Me, Et,21 CF3,34 para-substituted aryls,3,35 Me-
OCH2,36 dialkynyls -CtC-(C6H4)2CtC-,31 or C6H3-
(CtC-)3-1,3,537 derivatives. A limited number of alky-
nylgold(I) complexes with isocyanide,1,2,8,34,38 amine,13,39
or ylide ligands40 have also been reported.
We describe here a wide variety of anionic and neutral
alkynylgold(I) complexes with ethynyl, propargyl, (tri-
methylsilyl)ethynyl, tert-butylethynyl, and 1,5-non-
adiyndiyl groups and amine, phosphine, isocyanide, or
carbene ligands. We have explored a wide variety of
synthetic methods. Some of these results have been the
subject of preliminary reports.41-43
Exp er im en ta l Section
t
2090 (w). 1H NMR: δ 1.18 (s, 18H, Bu). 13C{1H} NMR: δ
28.25 (s, CMe3), 32.71 (s, Me), 111.11 (s, CtBu), 117.35 (s, CAu).
3: Yield 57%. Mp: 180 °C. Anal. Calcd for C46H48AuNP2-
Si2: C, 59.61; H, 5.20; N, 1.51. Found: C, 58.99; H, 5.18; N,
1.67. ΛM (Ω-1 cm2 mol-1): 95. IR (cm-1): ν(CtC), 2025 (w).
1H NMR: δ 0.03 (s, 18 H, Me). 4: Yield 92%. Mp: 135 °C
(dec). Anal. Calcd for C42H34AuCl2NP2: C, 57.16; H, 3.88; N,
1.59. Found: C, 57.12; H, 3.76; N, 1.62. ΛM (Ω-1 cm2 mol-1):
107. IR (cm-1): ν(CtC), 2125 (w). 1H NMR: δ 4.27 (s, 4H,
CH2). 13C{1H} NMR: δ 34.24 (s, CH2), 95.70 (s, CCH2), 130.68
(s, CAu). 5: Yield 84%. Mp: 120 °C (dec). Anal. Calcd for
Unless otherwise stated, NMR spectra were recorded in
CDCl3 in a Varian Unity 300 at room temperature. Chemical
shifts are referred to TMS (1H, 13C) or H3PO4 (31P). All of the
anionic complexes show, with very small differences, IR
absorptions at 1581 (m), 1320-1220 (s, br), 544 (s), 527 (s),
1
and 491 (s) cm-1 and H NMR resonances at 7.3-7.7 (m) and
1
13C{1H} NMR resonances at 127 (dd of an AA′ system, J CP
)
4
108 Hz, J CP ) 0.8 Hz, ipso-C), 130 (m, o-C), 132 (m, m-C),
and 134 (m, p-C) assignable to the [(PPh3)2N] cation and are
not given below. Molar conductivities are measured in acetone
solutions (1-6 × 10-4 mol L-1). Unless otherwise stated, the
neutral complexes show molar conductivities (ΛM) in the range
0-2 Ω-1 cm2 mol-1. The synthesis, spectroscopic and analyti-
cal data, and the crystal structure of 24 were preliminarly
reported by us.42
C42
H34AuBr2NP2: C, 51.93; H, 3.53; N, 1.44. Found: C, 51.54;
H, 3.37; N, 1.45. ΛM (Ω-1 cm2 mol-1): 134. IR (cm-1): ν(CtC),
2120 (w). 1H NMR (200 MHz): δ 4.136 (s, 4H, CH2). 13C{1H}
NMR: δ 20.35 (s, CH2), 114.10 (s, CCH2). 6: Yield 83%. Mp:
143 °C (dec). Anal. Calcd for C42H36AuNO2P2: C, 59.65; H,
4.29; N, 1.66. Found: C, 59.76; H, 4.31; N, 1.69. ΛM (Ω-1 cm2
mol-1): 80. IR (cm-1): ν(O-H), 3416 (m); ν(CtC), 2110 (m).
1H NMR: δ 4.27 (s, 4H, CH2). 13C{1H} NMR: δ 52.41 (s, CH2),
100.13 (s, CCH2), 127.29 (s, CAu). Single crystals of 6 were
obtained by slow diffusion of diethyl ether into a solution of 6
in dichloromethane.
t
[(P P h 3)2N][Au (CtCR)2] (R ) H (1), Bu (2), SiMe3 (3),
CH2Cl (4), CH2Br (5), CH2OH (6)). Complexes 1-6 were
(21) Cross, R. J .; Davidson, M. F. J . Chem. Soc., Dalton Trans. 1986,
411.
(22) Werner, H.; Otto, H.; Ngo-Kha, T.; Burschka, C. J . Organomet.
Chem. 1984, 262, 123.
[(P P h 3)2N][Au (CtCH)X] (X ) Cl (7), Br (8), I (9)).
Complexes 7-9 were obtained by reacting equimolar amounts
of 1 (ca. 0.2 mmol) and the corresponding [(PPh3)2N][AuX2]
complexes in dichloromethane for 1 h. The resulting solutions
were filtered through Celite and concentrated (ca. 3 mL), and
diethyl ether (20 mL) was added to precipitate white solids,
which were recrystallized from dichloromethane/diethyl ether.
7: Yield 86%. Mp: 192 °C. Anal. Calcd for C38H31AuClNP2:
C, 57.37; H, 3.93; N, 1.76. Found: C, 56.91; H, 3.91; N, 1.78.
(23) Payne, N. C.; Puddephatt, R. J .; Ravindranath, R.; Treurnicht,
I. Can. J . Chem. 1988, 66, 3167.
(24) Bruce, M. I.; Liddell, M. J . J . Organomet. Chem. 1992, 427,
263.
(25) Mitchell, C. M.; Stone, F. G. A. J . Chem. Soc., Dalton Trans.
1972, 102.
(26) J ohnson, A.; Puddephatt, R. J . J . Chem. Soc., Dalton Trans.
1977, 1384.
(27) Cross, R. J .; Davidson, M. F.; McLennan, A. J . J . Organomet.
Chem. 1984, 265, C37.
(28) Muller, T. E.; Mingos, D. M. P.; Williams, D. J . J . Chem. Soc.,
Chem. Commun. 1994, 1787.
(29) Yam, V. W.-W.; Choi, S. W.-K.; Cheung, K.-K. Organometallics
1996, 15, 1734.
(30) Payne, N. C.; Ramachandran, R.; Puddephatt, R. J . Can. J .
Chem. 1995, 73, 6.
(31) J ia, G.; Puddephatt, R. J .; Scott, J . D.; Vittal, J . J . Organome-
tallics 1993, 12, 3565.
(32) Nast, R. Angew. Chem. 1965, 77, 352.
(33) Nast, R.; Kirner, U. Z. Anorg. Allg. Chem. 1964, 330, 311.
(34) J ia, G.; Payne, N. C.; Puddephat, R. J . Organometallics 1993,
12, 4771.
(35) Bruce, M. I.; Horn, E.; Matisons, J . G.; Snow, M. R. Aust. J .
Chem. 1984, 37, 1163.
(36) Carriedo, G. A.; Riera, V.; Solans, X.; Solans, J . Acta Crystal-
logr., Sect. C 1988, 44, 978.
(37) Irwin, M. J .; Manojlovic-Muir, L.; Muir, K. W.; Puddephatt, R.
J .; Yufit, D. S.; Hussain, M. S.; Schlemper, E. O. Chem. Commun. 1997,
219.
(38) J ia, G.; Puddephatt, R. J .; Vittal, J . J .; Payne, N. C. Organo-
metallics 1993, 12, 263.
(39) Yau, J .; Mingos, D. M. P. J . Chem. Soc., Dalton Trans. 1997,
1103.
(40) Aguirre, C. J .; Gimeno, M. C.; Laguna, A.; Laguna, M.; Lo´pez
de Luzuriaga, J . M.; Puente, F. Inorg. Chim. Acta 1993, 208, 31.
(41) Vicente, J .; Chicote, M. T.; Abrisqueta, M. D. J . Chem. Soc.,
Dalton Trans. 1995, 497.
Λ
M (Ω-1 cm2 mol-1): 116. IR (cm-1): ν(CH), 3270 (vw); ν(CtC),
1982 (w). 1H NMR (200 MHz): δ 1.63 (s, 1H, CH). 13C{1H}
NMR: δ 83.75 (s, CH). 8: Yield 93%. Mp: 186 °C. Anal.
Calcd for C38H31AuBrNP2: C, 54.30; H, 3.72; N, 1.67. Found:
C, 54.29; H, 3.74; N, 1.71. ΛM (Ω-1 cm2 mol-1): 139. IR (cm-1):
ν(CH), 3266 (vw); ν(CtC), 1980 (w). 1H NMR: δ 1.65 (s, 1H,
CH). 13C{1H} NMR (50 MHz): δ 83.37 (s, CH). 9: Yield 85%.
Mp: 185 °C. Anal. Calcd for C38H31AuINP2: C, 51.43; H, 3.53;
N, 1.58. Found: C, 51.75; H, 3.53; N, 1.63. ΛM (Ω-1 cm2
mol-1): 131. IR (cm-1): ν(CH), 3268 (vw); ν(CtC), 1964 (w).
1H NMR (200 MHz): δ 1.63 (s, 1H, CH). 13C{1H} NMR: δ
82.20 (s, CH).
t
[Au (CtCR)(NHEt2)] (R ) SiMe3 (10), Bu (11)). [AuCl-
(tht)] (tht ) tetrahydrothiophene) (ca. 1 mmol) was treated
with an equimolar amount of the corresponding alkyne in
diethylamine (15 mL) for 30 min. The resulting suspensions
were filtered to remove (NH2Et2)Cl, and the solutions were
concentrated (ca. 2 mL) and cooled at -10 °C for 2 h to give
white solids, which were filtered off and dried in the air. 10:
Yield 73%. Mp: 20 °C (dec). Anal. Calcd for C9H20AuNSi:
C, 29.43; H, 5.49; N, 3.81. Found: C, 29.41; H, 5.42; N, 3.70.
IR (cm-1): ν(N-H), 3156 (m); ν(CtC), 2054 (m). 1H NMR (200
MHz): δ 0.07 (s, 9H, SiMe3), 1.39 (m, 6H, CH2Me), 2.92 (m,
4H, CH2), 4.87 (s, 1H, NH). 13C{1H} NMR: δ 0.87 (s, SiMe3),
(42) Vicente, J .; Chicote, M.-T.; Abrisqueta, M.-D.; Guerrero, R.;
J ones, P. G. Angew. Chem., Int. Ed. Engl. 1997, 36, 1203.
(43) Vicente, J .; Chicote, M. T.; Saura-Llamas, I.; Lagunas, M. C.
J . Chem. Soc., Chem. Commun. 1992, 915.

5630 Organometallics, Vol. 16, No. 26, 1997
Vicente et al.
14.70 (s, CH2Me), 48.67 (s, CH2), 108.85 (s, CSi), 126.56 (s,
CAu). 11: Yield 48%. Mp: 65 °C (dec). Anal. Calcd for
stirring, the resulting suspension was filtered to remove the
insoluble (NH2Et2)Cl. The solution was concentrated (ca. 1
mL), and n-hexane (20 mL) was added to precipitate white
solids, which were filtered off, washed with n-hexane (2 mL),
and air dried. 17: Yield 87%. Mp: 149 °C. Anal. Calcd for
C23H24AuPSi: C, 49.64; H, 4.21. Found: C, 49.84; H, 4.34. IR
(cm-1), ν(CtC), 2060 (s). 1H NMR (200 MHz): δ 0.17 (s, 9 H,
SiMe3), 7.38-7.46 (m, 15 H, Ph). 13C{1H} NMR (50 MHz): δ
C
10H20AuN: C, 34.20; H, 5.74; N, 3.99. Found: C, 33.64; H,
5.55; N, 3.72. IR (cm-1): ν(N-H), 3154 (w). 1H NMR (200
t
MHz): δ 1.25 (s, 9H, Bu), 1.45 (m, 6H, CH2Me), 2.98 (m, 4H,
CH2), 4.99 (s, 1H, NH). 13C{1H} NMR: δ 14.64 (s, CH2Me),
28.40 (s, CMe3), 32.24 (s, Me), 48.76 (s, CH2), 90.46 (s, CtBu),
112.96 (s, CAu).
3
0.75 (s, SiMe3), 109.47 (d, CSiMe3, J CP ) 19.8 Hz), 128.91 (d,
[Au (CtCH)(P P h 3)] (12). To a solution of [Au(PPh3)2]ClO4
(205 mg, 0.25 mmol) in acetone (20 mL) was added 1 (196 mg,
0.25 mmol), and the reaction mixture was stirred for 24 h. 12
(132 mg, 0.27 mmol) precipitated as a white solid, which was
filtered off, washed with n-hexane (5 mL), and air dried. The
solution was concentrated to dryness, and the residue was
extracted 3 times with a mixture of acetone (5 mL) and Et2O
(20 mL) to give insoluble [(PPh3)2N]ClO4 (130 mg, 0.20 mmol)
and a solution which, upon concentration (2 mL) and addition
of n-hexane (20 mL), gave a second crop of 12 (63 mg, 0.13
3
1
Ph, J CP ) 11.2 Hz), 129.39 (d, Ph, J CP ) 55.4 Hz), 131.39 (d,
4
2
Ph, J CP ) 2.4 Hz), 134.00 (d, Ph, J CP ) 13.7 Hz), 149.77 (d,
CAu, J CP ) 131.6 Hz). 31P{1H}, 41.29 (s). 18: Yield 77%.
2
Mp: 115 °C. Anal. Calcd for C23H42AuPSi: C, 48.08; H, 7.37.
Found: C, 48.35; H, 7.58. IR (cm-1), ν(CtC), 2056 (s). 1H
NMR: δ 0.13 (s, 9 H, SiMe3), 1.18-1.92 (m, 33 H, Cy). 13C-
{1H} NMR (50 MHz): 0.83 (s, SiMe3), 25.70 (s, Cy), 26.95 (d,
2
1
Cy, J CP ) 11.7 Hz), 30.43 (s, Cy), 32.95 (d, Cy, J CP ) 27.6
3
2
Hz), 108.16 (d, CSiMe3, J CP ) 19.9 Hz), 154.48 (d, CAu, J CP
) 122 Hz). 31P{1H} NMR: δ 55.20 (s). 19: Yield 80%. Mp:
193 °C (lit.35 181-2 °C). Anal. Calcd for C24H24AuP: C, 53.34;
H, 4.48. Found: C, 52.98; H, 4.48. IR (cm-1): ν(CtC), 2118
mmol). Yield: 80%. Mp: 168 °C. Anal. Calcd for C20H16
-
AuP: C, 49.60; H, 3.33. Found: C, 49.70; H, 3.25. IR (cm-1):
ν(CH), 3272 (vw); ν(CtC), 1981 (w). 1H NMR: δ 1.83 (s, 1H,
CH), 7.4-7.6 (m, 15H, PPh3). 13C{1H} NMR (50 MHz): δ 90.06
(d, CH, 3J CP ) 10 Hz), 129.20 (d, PPh3, 3J CP ) 11.4 Hz), 129.59
(d, PPh3, 1J CP ) 56 Hz), 131.66 (d, PPh3, 4J CP ) 2.5 Hz), 134.30
(w) (lit.35 2140). 1H NMR: δ 1.33 (s, 9 H, Bu), 7.42-7.53 (m,
t
15 H, Ph). 13C{1H} NMR: δ 28.12 (s, CMe3), 32.23 (s, Me),
114.50 (d, CtBu, J CP ) 25.7 Hz), 116.41 (d, CAu, J CP )141
3
2
3
1
2
(d, PPh3, J CP ) 14.1 Hz). 31P{1H} NMR: δ 42.43 (s).
Hz), 128.91 (d, Ph, J CP ) 11.0 Hz), 129.86 (d, Ph, J CP ) 55.4
4
2
Hz), 131.32 (d, Ph, J CP ) 2.6 Hz), 134.18 (d, Ph, J CP ) 14.1
Hz). 31P{1H}, 42.09 (s). 20: Yield 54%. Mp: 195 °C. Anal.
Calcd for C24H42AuP: C, 51.61; H, 7.58. Found: C, 51.20; H,
7.80. IR (cm-1): ν(CtC), 2109 (vw). 1H NMR (200 MHz): δ
1.20-1.90 (m, 33 H, Cy), 1.25 (s, 9 H, tBu). 13C{1H} NMR (50
[Au (CtCR)(P R′3)] (R ) H, R′ ) C6H4OMe-4 (13); R′ )
Cy, R ) CH2Cl (14), CH2Br (15), CH2OH (16)). A solution
of [Au(acac)(PR′3)] (ca. 0.5 mmol) in CH2Cl2 (15 mL) was slowly
added to a solution of the corresponding alkyne (molar ratio
1:1.1) in dichloromethane (5 mL) under a nitrogen atmosphere.
For the synthesis of 13, a saturated solution of acetylene in
degassed dichloromethane (20 mL) was used and bubbling of
acetylene was continued during the reaction. After 3 (13-
15) or 4.5 h (16) of stirring, the resulting suspensions were
filtered through anhydrous MgSO4, the solutions were con-
centrated (1 mL), and n-hexane (20 mL) was added to
precipitate white solids, which were filtered off and air dried.
13: Yield 70%. Mp: 123 °C. Anal. Calcd for C23H22AuO3P:
C, 48.10; H, 3.86. Found: C, 48.07; H, 3.76. IR (cm-1): ν-
(CH), 3268 (vw); ν(CtC), 1971 (w). 1H NMR: δ 1.81 (d, 1H,
2
MHz): 25.83 (s, Cy), 27.09 (d, Cy, J CP ) 11.7 Hz), 28.08 (d,
4
CMe3, J CP ) 1.7 Hz), 30.52 (s, Cy), 32.33 (s, Me), 33.11 (d,
1
3
Cy, J CP ) 27.6 Hz), 113.46 (d, CtBu, J CP ) 23.9 Hz), 120.89
(d, CAu, J CP ) 131.2 Hz). 31P{1H}, 55.30 (s). Single crystals
2
of 17 and 19 were obtained by slow evaporation of n-hexane
solutions.
[(Au P P h 3)2{µ-CtC(CH2)5CtC}] (21). HCtC(CH2)5CtCH
(31 µL, 0.21 mmol) was added to a suspension of [AuCl(PPh3)]
(207 mg, 0.42 mmol) in HNEt2 (15 mL), and the reaction
mixture was stirred for 24 h. The resulting suspension was
filtered, and the solid residue was washed with distilled water
(2 × 5 mL) and dissolved in CH2Cl2 (10 mL). This solution
was filtered through MgSO4 and concentrated to 1 mL.
Addition of n-hexane (15 mL) gave 21 as a white solid. Yield:
52%. Mp: 82 °C. Anal. Calcd for C45H40Au2P2: C, 52.14; H,
3.89. Found: C, 52.04; H, 3.96. 1H NMR: δ 1.58-1.65 (m,
4
CH, J HP ) 4.8 Hz), 3.82 (s, 9H, Me), 6.94 (m, 6H, Ph), 7.43
(m, 6H, Ph). 13C{1H} NMR: δ 55.42 (s, Me), 90.48 (d, CH,
3
3J CP ) 26.2 Hz), 114.67 (d, Ph, J CP ) 12.6 Hz), 121.3 (d, Ph,
2
1J CP ) 61.5 Hz), 126.3 (d, CAu, J CP ) 140 Hz), 135.6 (d, Ph,
2J CP ) 15.1 Hz), 162.0 (d, Ph, 4J CP ) 2 Hz). 31P{1H}, 37.93 (s).
14: Yield 57%. Mp: 142 °C. Anal. Calcd for C21H35AuClP:
C, 45.78; H, 6.40. Found: C, 45.49; H, 6.44. IR (cm-1): ν-
(CtC), 2132 (w). 1H NMR: δ 1.20-2.05 (m, 33 H, Cy), 4.29
(d, 2 H, CH2, 4J HP ) 1.5 Hz). 13C{1H} NMR (50 MHz): δ 25.81
3
6H, CH2), 2.38 (t, 4 H, CH2, J HH ) 6.9 Hz), 7.39-7.55 (m, 30
H, PPh3). 13C{1H} NMR: δ 19.87 (s, CH2), 28.92 (s, CH2), 29.85
(s, CH2), 105.71 (d, tC-CH2, 3J CP ) 25.7 Hz), 119.28 (d, CAu,
3
2J CP ) 142 Hz), 128.99 (d, Ph, J CP ) 11.1 Hz), 129.78 (d, Ph,
2
(s, Cy), 27.05 (d, Cy, J CP ) 11.9 Hz), 30.65 (s, Cy), 32.50 (s,
2
1J CP ) 55.9 Hz), 131.37 (s, Ph), 134.25 (d, Ph, J CP ) 14.1 Hz)
1
3
CH2), 32.60 (d, Cy, J CP ) 28.1 Hz), 97.47 (d, tCCH2, J CP
)
31P{1H}, 41.96 (s).
24.3 Hz), 133.77 (d, CAu, J CP ) 130.9 Hz). 31P{1H} NMR: δ
55.63 (s). 15: Yield 54%. Mp: 140 °C. Anal. Calcd for
2
[Au (CtCR)(P R′3)] (R′ ) C6H4OMe-4; R ) SiMe3 (22), tBu
(23)). To yellow solutions of 10 or 11 (ca. 1 mmol) in
dichloromethane (10 mL) was added an equimolar amount of
solid P(C6H4OMe-4)3. The solutions were stirred for 15 min
and concentrated to 1 mL, and n-hexane (20 mL) was added
to give white solids, which were filtered off and air dried. 22:
Yield 78%. Mp: 116 °C. Anal. Calcd for C26H30AuO3PSi: C,
48.30; H, 4.68. Found: C, 48.38; H, 4.66. IR (cm-1): ν(CtC),
2056 (s). 1H NMR: δ 0.20 (s, 9 H, SiMe3), 3.81 (s, 9 H, OMe),
6.91 (m, 6 H, C6H4), 7.40 (m, 6 H, C6H4). 13C{1H} NMR: δ
0.90 (s, SiMe3), 55.35 (s, OMe), 109.71 (d, CSiMe3, 3J CP ) 21.6
C
21H35AuBrP: C, 42.37; H, 5.92. Found: C, 42.58; H, 6.15.
IR (cm-1): ν(CtC), 2128 (w). 1H NMR (200 MHz): δ 1.26-
2.05 (m, 33 H, Cy), 4.10 (d, 2 H, tCCH2, J HP ) 1.2 Hz). 13C-
4
{1H} NMR (50 MHz): δ 17.45 (d, tCCH2, 4J CP ) 2.5 Hz), 25.81
2
(s, Cy), 27.05 (d, Cy, J CP ) 11.8 Hz), 30.67 (s, Cy), 33.15 (d,
Cy, J CP ) 27.4 Hz). 31P{1H} NMR: δ 55.58 (s). 16: Yield
1
72%. Mp: 147 °C. Anal. Calcd for C21H36AuOP: C, 47.37;
H, 6.81. Found: C, 47.32; H, 6.97. IR (cm-1): ν(O-H), 3470
(vw); ν(CtC), 2126 (w). 1H NMR: δ 1.23-2.01 (m, 33 H, Cy),
4
4.36 (d, 2 H, tCCH2, J HP ) 6 Hz). 13C{1H} NMR (50 MHz):
2
3
1
δ 25.69 (s, Cy), 26.91 (d, Cy, J CP ) 11.7 Hz), 30.52 (s, Cy),
Hz), 114.58 (d, C6H4, J CP ) 12.6 Hz), 121.42 (d, C6H4, J CP
)
1
2
32.91 (d, Cy, J CP ) 27.9 Hz), 51.73 (s, tCCH2), 101.78 (d,
60.9 Hz), 135.62 (d, C6H4, J CP ) 15.1 Hz), 150.36 (d, CAu,
3
2
2J CP ) 131.9 Hz), 161.96 (d, C6H4, 4J CP ) 2 Hz). 31P{1H}, 37.86
tCCH2, J CP ) 23.3 Hz), 130.89 (d, CAu, J CP ) 128.5 Hz).
31P{1H} NMR: δ 55.81 (s). Single crystals of 14 and 15 were
obtained by slow evaporation of n-hexane solutions.
(s). 23: Yield 83%. Mp: 172 °C. Anal. Calcd for C27H30
-
AuO3P: C, 51.44; H, 4.80. Found: C, 51.45; H, 4.83. IR
[Au (CtCR)(P R′3)] (R ) SiMe3, R′ ) P h (17), Cy (18); R
(cm-1): ν(CtC), 2112 (vw). 1H NMR (200 MHz): δ 1.33 (s, 9
t
t
) Bu , R′ ) P h (19), Cy (20)). To a suspension of [AuCl-
H, Bu), 3.82 (s, 9 H, OMe), 6.91 (m, 6 H, C6H4), 7.43 (m, 6 H,
(PR′3)] (ca. 1 mmol) in diethylamine (10 mL) was added the
C6H4). 13C{1H} NMR (50 MHz): δ 28.19 (s, CMe3), 32.31 (s,
CMe3), 55.32 (s, OMe), 102.41 (d, CtBu, 3J CP ) 21.4 Hz), 114.46
corresponding alkyne in a 1:1.05 molar ratio. After 24 h of

Neutral and Anionic Alkynylgold(I) Complexes
Organometallics, Vol. 16, No. 26, 1997 5631
3
2
3
(d, C6H4, J CP ) 12.3 Hz), 116.78 (d, CAu, J CP ) 141.6 Hz),
NMR (200 MHz): δ 1.16 (t, 3 H, MeCH2, J HH ) 7.3 Hz), 1.25
1
2
3
121.7 (d, C6H4, J CP ) 60.6 Hz), 135.64 (d, C6H4, J CP ) 15.4
(t, 3 H, MeCH2, J HH ) 7.2 Hz), 1.61 (s, 18 H, CMe3), 2.36 (t,
Hz), 161.84 (d, C6H4, J CP ) 1.7 Hz). 31P{1H} NMR: δ 38.39
4 H, CH2, J HH ) 7.6 Hz), 3.23 (q, 4 H, NCH2, J HH ) 7.3 Hz),
4
3
3
3
(s).
3.996 (q, 4 H, NCH2, J HH ) 7.2 Hz), 5.83 (s, 2 H, NH). 13C-
{1H} NMR: δ 11.79 (s, Me), 14.79 (s, Me), 20.35 (s, CH2), 29.18
(s, CH2), 30.17 (s, CH2), 31.88 (s, CMe3), 39.82 (s, NCH2), 53.77
(s, CMe3), 53.95 (s, NCH2), 106.53 (s, tC-CH2), 112.63 (s,
tCAu), 205.80 (s, CN2).
[Au (CtCtBu )(CNtBu )] (25). To a suspension of [Au-
Cl(CNtBu)] (316 mg, 1.00 mmol) in triethylamine (5 mL),
tBuCtCH was added (90 mg, 1.10 mmol). After 72 h, the
suspension was filtered, the solid washed with water (5 mL)
to remove (NHEt3)Cl dissolved in CH2Cl2 (10 mL), and the
solution filtered through MgSO4. Concentration of the solu-
tion (ca. 1 mL) and addition of n-hexane (20 mL) gave 25 as a
white solid. Yield: 221 mg, 61%. Mp: 82 °C. Anal. Calcd
for C11H18AuN: C, 36.57; H, 5.02; N, 3.88. Found: C, 36.57;
H, 5.02; N, 3.81. IR (cm-1): ν(CN), 2226 (s). 1H NMR (200
[Au Cl{C(NHtBu )(NEt2)}] (30). A solution of [AuCl(CN-
tBu)] (370 mg, 1.17 mmol) in diethylamine (5 mL) was stirred
for 5 h. The solvent was removed in vacuo, and the residue
was extracted with CH2Cl2 (10 mL) and filtered through
MgSO4. Addition of n-hexane (15 mL) to the solution gave an
oily material, which upon stirring for 1 h gave a white solid.
t
MHz): δ 1H, 1.18 (s, 9 H, C2 Bu), 1.46 (s, 9 H, CNtBu). 13C{1H}
Yield: 381 mg, 84%. Mp: 82 °C. Anal. Calcd for C9H20
-
NMR: δ 28.02 (s, CtBu), 29.76 (s, Me (CNtBu)), 32.17 (s, Me
AuClN2: C, 27.81; H, 5.19; N, 7.21. Found: C, 27.87; H, 5.18;
N, 7.08. IR (cm-1): ν(NH), 3360 (w); ν(CdN), 1538 (s); ν(Au-
t
(C2 Bu)), 58.32 (s, NCMe3), 106.52 (s, CtBu), 114.07 (s, AuCtC),
Cl), 328 (s). 1H NMR (200 MHz): δ 1.21 (t, 3 H, CH2Me, J HH
3
1
147.50 (t, AuCN, J CN ) 20 Hz).
3
[(Au CNtBu )2{µ-CtC(CH2)5CtC}] (26). To a suspension
of [AuCl(CNtBu)] (325 mg, 1.03 mmol) in NEt3 (10 mL) was
added HCtC(CH2)5CtCH (75 µL, 0.51 mmol). After 24 h of
stirring, the reaction mixture was worked up as described
above for 25, giving 26 as a white solid. Yield: 234 mg, 67%.
Mp: 117 °C (dec). Anal. Calcd for C19H28Au2N2: C, 33.64; H,
4.16; N, 4.13. Found: C, 33.76; H, 4.21; N, 4.54. IR (cm-1):
) 7.3 Hz), 1.29 (t, 3 H, CH2Me, J HH ) 7.0 Hz), 1.64 (s, 9 H,
tBu), 3.33 (q, 2 H, CH2, 3J HH ) 7.3 Hz), 3.98 (q, 2 H, CH2, 3J HH
) 7.0 Hz), 5.82 (s, 1 H, NH). 13C{1H} NMR: δ 11.75 (s,
CH2Me), 14.61 (s, CH2Me), 31.65 (s, Me (tBu)), 40.38 (s, CH2),
54.08 (s, CMe3), 54.99 (s, CH2), 188.95 (s, CAu).
[Au (CtCH){C(NHtBu )(NEt2)}] (31). To a solution of 30
(298 mg, 0.77 mmol) in acetone (20 mL), [Tl(acac)] (317 mg,
1.05 mmol) was added, and the resulting suspension was
stirred for 40 min and filtered through Celite. After C2H2 was
bubbled into the solution for 2 h, it was filtered through Celite
and concentrated (1 mL) and diethyl ether (20 mL) was added
to precipitate a white solid. Yield: 140 mg, 48%. Mp: 115
°C. Anal. Calcd for C11H21AuN2: C, 34.93; H, 5.59; N, 7.41.
Found: C, 34.82; H, 5.82; N, 7.44. ΛM (Ω-1 cm2 mol-1): 29.
IR (cm-1): ν(CH), 3266 (w); ν(NH), 3204 (m); ν(CtC), 1932
(w); ν(CdN), 1562 (m). 1H NMR (200 MHz): δ 1.18 (t, 3H,
ν(CN), 2224 (s). 1H NMR (200 MHz): δ H, 1.50-1.69 (m, 6
1
H, CH2), 1.56 (s, 18 H, tBu), 2.32 (t, 4 H, CH2). 13C{1H} NMR:
δ 19.81 (s, CH2), 28.64 (s, CH2), 29.71 (s, CH2), 29.78 (s, Me),
57.75 (s, CMe3), 104.80 (s, CtCAu), 109.55 (s, CAu).
[Au (CtCR ){C(NHt Bu )(NE t2)}] (R ) SiMe3 (27), t Bu
(28)). To a solution of [AuCl(CNtBu)] (1 mmol) in diethylamine
(10 mL) was added the corresponding alkyne (molar ratio of
1:1), and the mixture was stirred for 17 (27) or 24 (28) h. The
resulting suspension was filtered and washed with water (2
mL) to remove (NH2Et2)Cl. The remaining solid was treated
with dichloromethane (10 mL) and filtered through MgSO4.
The solution was concentrated (ca. 1 mL), and n-hexane (15
mL) was added to give white solids, which were filtered off,
washed with n-hexane (2 mL), and air dried. 27: Yield: 79%.
Mp: 143 °C. Anal. Calcd for C14H29AuN2Si: C, 37.33; H, 6.49;
N, 6.22. Found: C, 37.50; H, 6.50; N, 6.31. IR (cm-1): ν(N-
H), 3344 (m); ν(CtC), 2050 (s); ν(CdN), 1538 (s). 1H NMR
3
3
CH2Me, J HH ) 7.2 Hz), 1.25 (t, 3H, CH2Me, J HH ) 7.0 Hz),
t
3
1.58 (s, 1H, CH), 1.62 (s, 9H, Bu), 3.35 (q, 2H, CH2, J HH
)
7.2 Hz), 3.95 (q, 2H, CH2, J HH ) 7.0 Hz). 13C{1H} NMR: δ
11.76 (s, CH2Me), 14.93 (s, CH2Me), 31.86 (s, Me (tBu)), 40.41
(s, CH2), 53.81 (s, CMe3), 54.15 (s, CH2), 77.21 (s, HCtC),
142.64 (s, AuCtC), 199.31 (s, CN2).
3
X-Ra y Str u ctu r e Deter m in a tion s of Com p ou n d s 6, 14,
15, 17, a n d 19. Crystal data: See Table 1. Data collection
and reduction: Crystals were mounted on glass fibers in inert
oil and transferred to the cold gas stream of a Siemens R3
diffractometer. Data were registered in ω-scan mode to 2θmax
) 50° (Mo KR radiation). Cell constants were refined from
setting angles of ca. 65 reflections to 2θ ) 25°. Absorption
corrections were based on ψ-scans. Structure solution and
refinement: The structures were solved by the heavy-atom
method and refined anisotropically on F2 using the program
3
(200 MHz): δ 0.18 (s, 9 H, SiMe3), 1.16 (t, 3 H, CH2Me, J HH
3
) 7.3 Hz), 1.25 (t, 3 H, CH2Me, J HH ) 7.1 Hz), 1.61 (s, 9 H,
tBu), 3.24 (q, 2 H, CH2, J HH ) 7.3 Hz), 4.0 (q, 2 H, CH2,
3
3J HH ) 7.1 Hz), 5.84 (s, 1 H, NH). 13C{1H} NMR: δ 1.13 (s,
SiMe3), 11.80 (s, CH2Me), 14.82 (s, CH2Me), 31.92 (s, Me
(tBu)), 39.88 (s, CH2), 53.81 (s, CMe3), 54.01 (s, CH2), 110.24
(s, CSiMe3), 145.82 (s, CtCAu), 205.45 (s, CN2). 28: Yield:
83%. Mp: 116 °C. Anal. Calcd for C15H29AuN2: C, 41.48; H,
6.73; N, 6.45. Found: C, 41.24; H, 6.81; N, 6.48. IR (cm-1):
ν(N-H), 3350 (m); ν(CtC), 2106 (vw); ν(CdN), 1538 (s). 1H
SHELXL-93 (G. M. Sheldrick, University of Go¨ttingen).
H
atoms were included using a riding model. Special features
of refinement: In compound 6, the hydroxyl H were not located;
one OH group is disordered (there are no short O‚‚‚O contacts
suggestive of H bonds). Compounds 14 and 15 are isostruc-
tural; the Br atom of 15 has a high U value. Residual electron
density near an inversion center in 19 was tentatively inter-
preted as a disordered molecule of NHEtCH2Cl.
3
NMR (200 MHz): δ 1.15 (t, 3 H, CH2Me, J HH ) 7.3 Hz), 1.24
3
(t, 3 H, CH2Me, J HH ) 7.4 Hz), 1.29 (s, 9 H, Me (CtC-
tBu)), 1.61 (s, 9 H, Me (NHtBu)), 3.22 (q, 2 H, CH2, J HH ) 7.3
3
Hz), 4.02 (q, 2 H, CH2, J HH ) 7.1 Hz), 5.81 (s, 1 H, NH). 13C-
3
{1H} NMR: δ 11.84 (s, CH2Me), 14.79 (s, CH2Me), 28.25 (s,
CtCCMe3), 31.95 (s, Me (NHtBu)), 32.61 (s, Me (CtCtBu)),
39.76 (s, CH2), 53.81 (s, NHCMe3), 54.05 (s, CH2), 109.72 (s,
CtCtBu), 115.40 (s, CtCAu), 206.09 (s, CN2).
Resu lts a n d Discu ssion
[{Au C(NHt Bu )(NE t2)}2{µ-CtC(CH2)5CtC}] (29). To a
solution of [AuCl(CNtBu)] (457 mg, 1.45 mmol) in diethylamine
(10 mL), HCtC(CH2)5CtCH (89 mg, 0.72 mmol) was added.
After 14 h of stirring, the resulting suspension was filtered
and the solid washed with water to remove (NH2Et2)Cl. The
residue was treated with dichloromethane (15 mL), the solu-
tion filtered through MgSO4 and concentrated (ca. 1 mL), and
n-hexane (20 mL) added to precipitate a white solid, which
was filtered off, washed with n-hexane (2 mL), and air dried.
Syn th esis. We have previously shown that acetyl-
acetonatogold(I) complexes are able to deprotonate
organic substrates containing even weakly acidic hy-
drogen atoms to give a variety of gold(I) complexes
containing ylide, thiolato, phosphide, bis(diphenylphos-
phino)methanide, alkyl (CHRR′ (R ) R′ ) CN, CO2Me;
R ) CN, R′ ) CO2Me)), or alkynyl ligands.41,43-50 The
extension of this method to the preparation of new
Yield: 332 mg, 56%. Mp: 90 °C. Anal. Calcd for C27H50
-
Au2N4: C, 39.32; H, 6.11; N, 6.79. Found: C, 39.59; H, 6.27;
(44) Vicente, J .; Chicote, M. T.; Lagunas, M. C. Inorg. Chem. 1993,
32, 3748.
N, 6.80. IR (cm-1): ν(N-H), 3338 (m); ν(CdN), 1538 (s). 1H

5632 Organometallics, Vol. 16, No. 26, 1997
Ta ble 1. Cr ysta l Da ta for Com p lexes 6, 14, 15, 17 a n d 19
Vicente et al.
6
14
15
17
19
molecular formula
mol wt
space group
a (Å)
b (Å)
c (Å)
R (deg)
â (deg)
γ (deg)
V (Å3)
C42H36AuNO2P2
845.62
P21/c
10.892(2)
21.823(2)
16.072(2)
90
108.413(10)
90
3624.8(9)
4
C21H35AuClP
550.88
P21/c
11.119(3)
16.732(3)
12.967(4)
90
114.92(2)
90
2187.8(10)
4
C21H35AuBrP
595.34
P21/c
11.314(2)
16.674(3)
12.959(2)
90
115.060(10)
90
2214.6(6)
4
C23H24AuPSi
556.45
P21/c
6.7192(10)
21.571(3)
15.962(2)
90
96.625(10)
90
2322.7(5)
4
C25.50H28AuCl0.50N0.50
587.15
C2/c
30.518(6)
8.601(2)
17.885(4)
90
93.61(2)
90
4686(2)
8
P
Z
T (K)
λ (Å)
173(2)
0.710 73
1.550
1680
4.183
6357
439
407
173(2)
0.710 73
1.672
1088
6.921
4984
217
39
173(2)
0.710 73
1.786
1160
8.520
3719
112
21
173(2)
0.710 73
1.591
1080
6.458
5335
247
87
173(2)
0.710 73
1.665
2296
6.415
4119
133
24
F
calc (Mg/m3)
F(000)
µ (mm-1
)
no. of indep reflns
no. of param
no. of restraints
R1a
0.0378
0.0580
0.819
0.0369
0.0870
0.942
0.0630
0.1788
1.037
0.0274
0.0446
0.831
0.0382
0.0923
0.915
wR2b
S(F2)
max ∆F (e Å-3
)
0.837
2.220
2.483
0.709
1.105
a
b
2
R1 ) ∑||Fo| - |Fc||/∑|Fo| for reflections with I > 2σI. wR2 ) [∑[w(Fo - Fc2)2]/Σ[w(Fo2)2]]0.5 for all reflections; w-1 ) σ2(F2) + (aP)2 +
bP, where P ) (2Fc + Fo2)/3 and a and b are constants set by the program.
2
only other [Au(CtCR)2]- complex known is that with
Sch em e 1
R ) Ph, prepared by Nast et al. by reacting [Au-
(CtCPh)]n with KCtCH in liquid ammonia.33,51
Alkynylhaloaurate(I) complexes [(PPh3)2N][Au-
(CtCH)X] (X ) Cl (7), Br (8), I (9)) were prepared in
high yield (84-95%) by reacting equimolar amounts of
1 and the corresponding [(PPh3)2N][AuX2] salts (see
Scheme 1). The only reported [Au(CtCR)X]- complexes
are those with R ) Ph and X ) Cl, Br, I obtained by
reacting [Au(CtCPh)]n with X-.9,52 However, no ex-
perimental details were reported.
We have attempted the synthesis of the mixed alkynyl
complex [(PPh3)2N][Au(CtCH)(CtCtBu)] by reacting
equimolar amounts of 1 and 2 in dichloromethane, but
1
bisalkynylaurate(I) complexes [(PPh3)2N][Au(CtCR)2]
(R ) H (1), Bu (2), SiMe3 (3), CH2Cl (4), CH2Br (5),
only a mixture of the starting complexes (by H NMR)
was recovered. The reaction of 1 with [(PPh3)2N][Au-
(SH)2]46 (1:1, dichloromethane) seems to produce an
equilibrium mixture (by 1H NMR) of the starting
complexes and, probably, [(PPh3)2N][Au(CtCH)(SH)],
which we could not separate. Scheme 1 summarizes the
reactions that lead to anionic alkynylgold(I) complexes
1-9.
t
CH2OH (6)) by reacting [(PPh3)2N][Au(acac)2] with the
corresponding alkyne provides a further example of the
synthetic utility of acetylacetonatogold(I) complexes (see
Scheme 1). The reactions were carried out using excess
alkyne (molar ratio ca. 1:40) in order to prevent the
formation of insoluble polymeric [Au(CtCR)]n species.
The complexes were obtained in high yield (83-95%)
and the excess of alkyne and the byproduct (acacH) were
easily removed. K[Au(CtCH)2] was reported long ago
by Nast et al. as a compound of very low stability to
moisture and light. In contrast, complex 1 is stable to
moisture and daylight. Our method of synthesis is
much simpler than that used to prepare the potassium
salt, which involved three steps and the use of liquid
ammonia, acetylene, KCtCH, Au2(CtC)‚NH3, and K2-
[Au2(µ-CtC)(CtCH)2].33 As far as we are aware, the
For the syntheses of neutral [Au(CtCR)L] (L )
amine, phosphine, isocyanide, or carbene) complexes, we
have used a variety of synthetic procedures (see Schemes
2 and 3). Thus, moderate to high (48-73%) yields of
the alkynyl(diethylamine)gold(I) complexes [Au(CtCR)-
t
(NHEt2)] (R ) SiMe3 (10), Bu (11)) were achieved by
reacting equimolar amounts of [AuCl(tht)] (tht ) tet-
rahydrothiophene) and the corresponding alkyne in
diethylamine. The alkynyl ligand generated in situ (on
deprotonation of the alkyne by the amine) and the
amine itself replace both tht and chloro ligands, forming
the desired complexes along with (NH2Et2)Cl. This
ammonium salt is easily removed because of its insolu-
bility in diethylamine, and the corresponding complex
(45) Vicente, J .; Chicote, M. T.; J ones, P. G. Inorg. Chem. 1993, 32,
4960.
(46) Vicente, J .; Chicote, M. T.; Gonza´lez-Herrero, P.; J ones, P. G.;
Ahrens, B. Angew. Chem., Int. Ed. Engl. 1994, 33, 1852.
(47) Vicente, J .; Chicote, M. T.; Gonza´lez-Herrero, P.; J ones, P. G.
J . Chem. Soc., Dalton Trans. 1994, 3183.
(48) Vicente, J .; Chicote, M. T.; Gonza´lez-Herrero, P.; J ones, P. G.
J . Chem. Soc., Chem. Commun. 1995, 745.
(49) Vicente, J .; Chicote, M. T.; Guerrero, R.; J ones, P. G. J . Am.
Chem. Soc. 1996, 118, 699.
(51) Nast, R.; Schneller, P.; Hengefeld, A. J . Organomet. Chem.
1981, 214, 273.
(52) Abu-Salah, O. M.; Al-Ohaly, A. R.; Al-Showiman, S. S.; Al-
Najjar, I. M. Transition Met. Chem. 1985, 10, 207.
(50) Vicente, J .; Chicote, M. T.; Rubio, C. Chem. Ber. 1996, 129, 327.

Neutral and Anionic Alkynylgold(I) Complexes
Organometallics, Vol. 16, No. 26, 1997 5633
Sch em e 2
Sch em e 3
precipitates on cooling the solution. Complexes [Au-
amine, intended to produce [Au(CtCSiMe3)(AsPh3)],
gives 10 instead.
(CtCR)(L)] (R ) Ph, L ) NH3, iPrNH2, tBuNH2, C5H11
-
n
NH2, C8H15NH2, C9H17NH2, Bu2NH, piperidine, pyri-
Alkynylgold(I) complexes with phosphine ligands have
been prepared (see Scheme 2) by four different synthetic
methods, namely (i) the reaction between equimolar
amounts of 1 and [Au(PR3)2]ClO4 to give [Au(CtCH)-
(PR3)] (R ) Ph (12), C6H4OMe-4 (13)) and [(PPh3)2N]-
ClO4, which could be separated because of the insolu-
bility of the latter in diethyl ether; (ii) reaction of
terminal alkynes with [Au(acac)PR3] to give acacH and
complexes [Au(CtCR)(PR′3)] (R ) H, R′ ) Ph (12), C6H4-
OMe-4 (13); R′ ) Cy ) cyclohexyl, R ) CH2Cl (14), CH2-
Br (15), CH2OH (16)). A slight excess of the alkyne was
used, except in the case of acetylene, which was used
in large excess to prevent the formation of mixtures that
we attribute to the reaction 2[Au(CtCH)L] f [L-
AuCtCAuL] + C2H2. Although the synthesis of 12 has
been reported, it was not obtained in pure form.21 (iii)
The reaction of [AuCl(PR3)] complexes with terminal
alkynes in diethylamine to give complexes [Au(CtCR)-
(PR′3)] (R ) SiMe3, R′ ) Ph (17), Cy (18); R ) tBu, R′ )
Ph (19), Cy (20)) and [(AuPPh3)2{µ-CtC(CH2)5CtC}]
(21). In this case, the alkynyl ligand resulting from
deprotonation of the alkyne by the diethylamine solvent
coordinates to gold with concomitant formation of
insoluble (NH2Et2)Cl, and (iv) the displacement of the
NHEt2 ligand present in complexes 10 or 11 by P(C6H4-
OMe-4)3 to give complexes [Au(CtCR)(P(C6H4OMe-4)3)]
t
t
t
dine; R ) Bu, L ) BuNH2; R ) Bu, C6H4Me-4, L )
NH3 have been prepared by reacting [Au(CtCR)]n with
the corresponding ligand13,39 or the alkyne with [AuL2]+.39
We have not been able to prepare [Au(CtCH)-
(NHEt2)] because the reaction of [AuCl(tht)] with C2H2
in diethylamine or triethylamine gives instead a brown
complex that detonates after drying when touched by a
spatula. We believe this complex to be the same
reported long ago as Au2C2.53 If Na2CO3 is used instead
of the amine, metallic gold is obtained. The same
explosive compound was formed in the following reac-
tions: [(PPh3)2N][Au(CtCH)Cl] + [Au(acac)(PCy3)] (but
not with [Au(acac){P(C6H4OMe-4)3}]); [Au(CtCSiMe3)-
(NHEt2)] + C2H2; [(PPh3)2N][Au(CtCH)2] + [AuCl(tht)];
[(PPh3)2N][AuCl4] + C2H2 + HNEt2; [Au(CtCSiMe3)-
(PPh3)] + AgClO4. Because of the extreme instability
of this compound, we have not attempted to characterize
it. However, we have carried out limited investigations
on its reactivity. Thus, the product from the reaction
of [AuCl(tht)] with C2H2 in diethylamine reacts with
P(C6H4OMe-4)3 to give a complex mixture that we could
not separate. However, the 31P NMR spectrum of one
of the fractions showed the presence of 13 and [AuCl-
(P(C6H4OMe-4)3)]. The reaction with tBuNC gave a
t
mixture with two resonances in the Bu region of the
1H NMR. It does not react with [(PPh3)2N][AuCl2]. The
t
reaction of [AuCl(AsPh3)] with Me3SiCtCH in diethyl-
(R ) SiMe3 (22), Bu (23)) in high yield (78-83%).
These reactions must be favored by the low affinity of
(53) Mathews, J . A.; Watters, L. L. J . Am. Chem. Soc. 1900, 22, 108.
the soft-acid gold(I) for hard-base nitrogen donor

5634 Organometallics, Vol. 16, No. 26, 1997
Vicente et al.
ligands.54 All four methods generally give high yields
(70-87%) of the organometallic complexes except for
those partially soluble in n-hexane, such as 14, 15, 20,
and 21 (50-60%). Complexes [Au(CtCR)(PR′3)] (R′ )
i
n
t
Ph, R ) Ph, C6H4Me-4, Me, Et, Pr, Pr, Bu, Bu, CF3,
C6F5, CH2OH, (CH2)2OH, C6H10OH, CO2Me; R′ ) Me,
R ) Me, tBu; R′ ) iPr, R ) H, CO2Me; R ) Ph, R′ ) Me,
OPh, Et, R′3 ) Ph2{CH2(anthracenyl)}, Ph(OMe)2; R )
CF3, R′3 ) PhMe2) are among the best known alky-
nylgold(I) derivatives. They have been prepared by
reacting (i) [Au(CtCR)]n with the corresponding phos-
phine,8,13,35 (ii) [AuCl(L)] with LiCtCR13 or with
NaCtCR21,35 or KCtCR,35 (iii) the alkyne with [AuMe-
(L)]25,26 or with [Au(NR2)(L)] (HNR2 ) imidazole)55 or
[Au(C5R′′5)(L)] (R′′ ) H, Me),22 (iv) [AuCl(L)] with the
alkyne in NHEt2 in the presence of CuCl.35 In our
experience, this last method does not in fact require the
presence of CuCl as catalyst.
[AuCl(CNtBu)] reacts with terminal alkynes in tri-
ethylamine to give moderate yields (36-67%) of the
corresponding alkynyl( isocyanide)gold(I) complexes
[Au(CtCR)(CNtBu)] (R ) SiMe3 (24),42 tBu (25)) and
[(AuCNtBu)2{µ-CtC(CH2)5CtC}] (26). The reactions
are similar to those described above for the syntheses
of complexes 17-21, except for the use of triethylamine
instead of diethylamine. It is well-known that primary
or secondary amines, and also alcohols, add to isocya-
nidegold(I) complexes to give the corresponding carbene
derivatives.56-59 Therefore, the use of diethylamine
must be avoided for the syntheses of isocyanide com-
plexes. In fact, when [AuCl(CNtBu)] and the same
alkynes that in triethylamine lead to isocyanide com-
plexes 24-26 are reacted in diethylamine, the corre-
sponding alkynyl(carbene)complexes [Au(CtCR){C(NH
F igu r e 1. Ellipsoid plot of compound 24 with labeling
scheme (50% probability levels). H atoms are omitted for
clarity. Selected bond distances (Å) and angles (deg): Au-
(1)-C(4) 1.95(5), Au(1)-C(1) 1.98(5), Au(1)-Au(2) 3.1244-
(10), Au(2)-C(7) 1.96(3), Au(2)-C(12) 2.02(2), N(1)-C(1)
1.17(5), N(2)-C(7) 1.15(3), C(4)-C(5) 1.18(6), C(12)-C(13)
1.21(3), C(4)-Au(1)-C(1) 180.00(2), C(7)-Au(2)-C(12)
177.9(10), Au(2)-Au(1)-Au(2′) 116.32(2).
NaOH or NaH was used as a base, total decomposition
to metallic gold occurred. Other attempts also failed.
For example, the reaction between [AuCl(tht)], C2H2/
Na2CO3, and CNBut gave [AuCl(CNBut)], whereas no
reaction took place between [AuCl(CNtBu)] and C2H2/
t
tBu)(NEt2)}] (R ) SiMe3 (27), Bu (28)) and [(Au{C-
t
Na2CO3 or 12 and BuNC. The ethynyl(carbene)gold(I)
(NHtBu)(NEt2)})2{µ-CtC(CH2)5CtC}] (29) are obtained
as the result of the double role of diethylamine as a
deprotonating agent toward the alkyne and as a nu-
cleophile adding to the isocyanide ligand. Similarly, the
isocyanide complex [AuCl(CNtBu)] reacts with diethy-
lamine to give the carbene complex [AuCl{C(NHtBu)-
(NEt2}] (30).
All attempts to prepare [Au(CtCH)(CNtBu)] failed.
Thus, from the reaction of [AuCl(CNtBu)] with acetylene
in triethylamine, the above-mentioned brown explosive
complex Au2C2 was obtained. The reaction of [Au-
Cl(CNtBu)] with Tl(acac) in dichloromethane gives
insoluble TlCl and a solution presumably containing
[Au(acac)(CNtBu)], which, however, could not be isolated
because of its oily nature. This complex was expected
to react with acetylene to give acacH and the ethynyl
complex, but unfortunately, on bubbling acetylene
through this solution, immediate partial decomposition
to metallic gold was observed and the resulting mixture
could not be separated. The same occurred when
acetylene was bubbled through a solution containing a
1:1 mixture of [AuCl(CNtBu)] and proton sponge. When
complex [Au(CtCH){C(NHtBu)(NEt2)}] (31) was ob-
tained by treating 30 with Tl(acac), removing TlCl, and
bubbling acetylene through the resulting solution.
Scheme 3 summarizes the reactions leading to isocya-
nide and carbene alkynylgold(I) complexes.
Gold(I) complexes containing alkynyl and isocyanide
ligands are of great interest because of their potential
applications as advanced materials (luminescent com-
pounds, liquid crystals, NLO, etc.). Compounds of the
family of 24 and 25, [Au(CtCR)(CNR′)] (R ) Ph, R′ )
nBu, C6H4Et-2, C6H4Me-4,13 C6H3Me2-2,5;60 R ) C6H4-
(CmH2m+1)-4 (m ) 6, 8, 10), R′ ) C6H4X-4 (X ) H,
OCnH2n+1 (n ) 2, 4, 6, 8, 10));1 R ) tBu, R′ ) C6H4CtCH,
C6H3(Me-2)(CtCH-4),34,38), or 26, [(AuCNR′)2{µ-CtC-
R-CtC}] (R ) C6H4, C6H4C6H4, C6H2Me2-2,5, CH2-
OC6H4C(Me2)C6H4OCH2, R′ ) C6H3Me2-2,62), have been
prepared by reacting [Au(CtCR)]n or [Au2{µ-CtC-R-
CtC}]n, respectively, with the corresponding isocyanide.
We are not aware of any report of alkynyl(carbene)gold
complexes such as 27-31.
Cr ysta l Str u ctu r es of com p lexes 6, 14, 15, 17, 19,
a n d 24. The crystal structure of 24 (see Figure 1) has
recently been reported by us.42 It shows a tetranuclear
loose cluster formed through a new aurophilic structural
motif: a central molecule (based on Au(1)) lying on a
crystallographic 3-fold axis, with three others (based on
the general Au(2)) connected to it by Au‚‚‚Au contacts
(54) Vicente, J .; Chicote, M. T.; Guerrero, R.; J ones, P. G. J . Chem.
Soc., Dalton Trans. 1995, 1251.
(55) Bonati, F.; Burini, A.; Pietroni, B. R.; Giorgini, E.; Bovio, B. J .
Organomet. Chem. 1988, 344, 119.
(56) Parks, J . E.; Balch, A. L. J . Organomet. Chem. 1974, 71, 453.
(57) Bonatti, F.; Minghetti, G. J . Organomet. Chem. 1973, 59, 403.
(58) Minghetti, G.; Baratto, L.; Bonatti, F. J . Organomet. Chem.
1975, 102, 397.
(59) McCleverty, J . A.; Da Mota, M. M. M. J . Chem. Soc., Dalton
Trans. 1973, 2571.
(60) Xiao, H.; Cheung, K.-K.; Che, C.-M. J . Chem. Soc., Dalton
Trans. 1996, 3699.

Neutral and Anionic Alkynylgold(I) Complexes
Organometallics, Vol. 16, No. 26, 1997 5635
F igu r e 2. Ellipsoid plot of the anion of compound 6 with
labeling scheme (50% probability levels). H atoms are
omitted for clarity. Selected bond lengths (Å) and angles
(deg): Au-C1 1.994(6), Au-C4 2.006(6), C1-C2 1.202(7),
C2-C3 1.471(7), C3-O1 1.397(6), C3-O1′ 1.449(11), C4-
C5 1.189(6), C5-C6 1.469(7), C6-O2 1.413(6), C1-Au-
C4 176.2(2), C2-C1-Au 174.1(6), C5-C4-Au 176.2(5).
F igu r e 4. Ellipsoid plot of compound 15 with labeling
scheme (50% probability levels). Selected bond lengths
(Å) and angles (deg): Au-C1 2.080(12), Au-P 2.285(4),
C1-C2 1.10(2), C1-Au-P 179.4(4), C(2)-C(1)-Au 179.1
(13).
F igu r e 3. Ellipsoid plot of compound 14 with labeling
scheme (50% probability levels). Selected bond lengths (Å)
and angles (deg): Au-C1 2.051(6), Au-P 2.292(2), C1-
C2 1.150(9), C1-Au-P 178.6(2), C(2)-C(1)-Au 177.8(5).
F igu r e 5. Ellipsoid plot of compound 17 with labeling
scheme (50% probability levels). Selected bond lengths (Å)
and angles (deg): Au-C1 2.000(4), Au-P 2.2786(10), C1-
C2 1.196(5), C2-Si 1.836(4), C1-Au-P 178.20(11), C(2)-
C(1)-Au 176.8(4), C1-C2-Si 177.6(4).
of 3.1244(10) Å. The central gold atom lies 0.61 Å out
of the plane formed by the other three. The repulsion
t
between the bulky SiMe3 and Bu groups is avoided by
parameters are similar to those found for other crystal
structures of alkynylgold(I) complexes.10,11,28,34,61-65
IR Sp ectr oscop y. The band assignable to the νCtC
stretching mode appears as a weak (R ) H, tBu),
medium (R ) CH2X, X ) Cl, Br, OH), or strong (R )
SiMe3) absorption, slightly shifted with respect to that
in the corresponding free alkyne. For the same R, the
wavenumber of νCtC follows the order [Au(CtCR)(L)]
(2132-1932 cm-1) g HCtCR (R ) CH2Cl (2127 cm-1),
rotation of the peripheral molecules by 121° (angle
between the vectors C1‚‚‚C4 and C7‚‚‚C12) with respect
to the central one. The isolated “aurophilic three-
coordination” found at the central gold atom is unprec-
edented. In contrast, the crystal structures of 6, 14, 15,
17, and 19 (see Figures 2-6) show no intermolecular
Au‚‚‚Au interactions. The anionic nature of 6 and the
presence of the bulky phosphine ligand PPh3 and PCy3
in the other complexes are probably responsible for this.
The gold atoms are in essentially linear environments,
with CAuC or CAuP angles of 176.2(2)° (6), 178.6(2)°
(14), 179.4(4)° (15), 178.20(11)° (17), 178.0(2)° (19) and
180° (24). The AuC and AuP bond distances are in the
ranges 1.994(6)-2.080(12) and 2.271(2)-2.292(2) Å,
respectively, while the CtC bond distances, necessarily
imprecise, range from 1.10(2) to 1.21(3) Å. All of these
(61) Corfield, P. W. R.; Shearer, H. M. M. Acta Crystallogr. 1967,
C23, 156.
(62) Abu-Salah, O. M.; Al-Ohaly, A. R.; Knobler, C. B. J . Chem. Soc.,
Chem. Commun. 1985, 1502.
(63) Bruce, M. I.; Grundy, K. R.; Liddell, M. J .; Snow, M. R.; Tieknik,
E. R. T. J . Organomet. Chem. 1988, 344, C49.
(64) Bruce, M. I.; Duffy, D. N. Aust. J . Chem. 1986, 39, 1697.
(65) Muller, T. E.; Choi, S. W.-K.; Mingos, D. M. P.; Murphy, D.;
Williams, D. J . J . Organomet. Chem. 1994, 484, 209.

5636 Organometallics, Vol. 16, No. 26, 1997
Vicente et al.
implying that in our complexes the isocyanide ligand
acts preferentially as a σ donor.68 Complexes with
diethylamine (10, 11) or carbene ligands (27-31) show
the corresponding νNH bands in the 3154-3156 or 3204-
3360 cm-1 range, respectively. The carbene complexes
also show a strong band in the 1538-1562 cm-1 region,
assignable to asymmetric stretching of the N-C-N
moiety.
NMR Sp ectr oscop y. The electronic effect of the
AuPR3 group on the resonance of the acetylenic proton
in complexes 12 (1.83 ppm) and 13 (1.81 ppm) is similar
to that of H in C2H2 (1.80 ppm). Probably, the shielding
effect arising from the substitution of the proton by the
less electronegative AuPR3 group is compensated by the
π-acceptor ability of the AuPR3 group, which reduces
the paramagnetic anisotropy of the CtC bond. The
anionic nature of complex 1 is probably responsible for
the high-field shift of the proton (1.37 ppm). The δ(H)
in the anionic halocomplexes 7-9 (1.63-1.65 ppm) and
the neutral carbene complex 31 (1.58 ppm) are similar
and intermediate between 1 and 12, 13.
F igu r e 6. Ellipsoid plot of compound 19 with labeling
scheme (50% probability levels). Selected bond lengths (Å)
and angles (deg): Au-C1 1.997(8), Au-P 2.271(2), C1-
C2 1.187(11), C2-C3 1.509(13), C1-Au-P 178.0(2), C(2)-
C(1)-Au 175.0(8), C1-C2-C3 179.3(9).
The 13C resonance corresponding to the carbon bonded
to gold (CR) in RCtCAuL complexes depends mainly on
R, with δ(CR) values (in ppm) for Me3Si (154.48-126.56)
> H (142.64-126.3) > tBu (120.89) when L is the same
ligand. In the anionic complexes the order is ClCH2
(130.68) > HOCH2 (127.29) = H (127.09) > tBu (117.35).
The influence of L on the shielding of the CR nucleus is
t
CH2OH (2119 cm-1), CH2Br (2118 cm-1), Bu (2109
cm-1), SiMe3 (2036 cm-1), H (1974 cm-1, Raman)) g
[Au(CtCR)2]- (2125-1971 cm-1), except in the case of
the neutral complex 31 (R ) H and L ) C(NHtBu)-
(NEt2)) whose value (1932 cm-1) is lower than those of
the alkyne (1974 cm-1) and that of the anionic complex
1 (1962 cm-1). When the anionic complexes are ordered
according to νCtC, the same series observed for the free
t
less marked, the order of δ(CR) in the Bu, Me3Si, and
the dinuclear 1,5-nonadiyndiyl complexes being PCy3
t
> PAr3 > C(NHtBu)(NEt2) > BuNC > Et2NH. In the
case of the ethynyl complexes with L ) C(NHtBu)(NEt2)
(31) and P(C6H4OMe-4)3 (13), the order is reversed.
Therefore, it seems that shielding of CR is greater for a
“σ-only” donor ligand such as Et2NH than for π-acceptor
ligands such as PR3, carbene, and isocyanide, as ex-
pected.
t
alkynes is obtained (CH2X > Bu > SiMe3 > H). The
same occurs with the neutral complexes. In this case,
although the nature of the neutral ligand causes little
t
differences in νCtC (2-10 cm-1), the order BuNC > PR3
> NHEt2 > C(NHtBu)(NEt2) is observed. In the anionic
ethynyl complexes 1, and 7-9, νCtC decreases in the
The 13C resonance corresponding to the carbon in the
â position with respect to gold (Câ) is practically
independent of the nature of L in the neutral Me3SiCtC
derivatives (110-108), whereas in the case of neutral
tBuCtC derivatives, the values of δ(Câ) are in the range
114.5-102.41 for π-acceptor ligands while a high-field
shift is found for L ) Et2NH (90.46). In the ethynyl
complexes, the values of δ(Câ) follow the order PAr3 (90)
> C(NHtBu)(NEt2) (77).
series Cl (1982 cm-1) = Br (1980 cm-1) > I (1964 cm-1
)
= CtCH (1962 cm-1). A similar result was observed
in phenylethynylgold(I) complexes.52 All of these IR
data are difficult to rationalize because νCtC depends
on the force constants of the tC-X bonds, the mass of
the substituents, and potential pπ-dπ bonding.66,67 The
ethynyl complexes 1, 7-9, 12, 13, and 31 show one weak
νCH band in the 3266-3272 region in their IR spectra
and a medium band at around 300 cm-1 (except 1) (325
(7), 323 (8, 9), 298 (12), 297 (13)) that we tentatively
assign to some vibration mode of the Au-C bond. In
the case of 7, this band could also involve ν(Au-Cl). The
hydroxypropargyl complexes 6 and 16 show a medium
νOH band at 3416 and 3470 cm-1, respectively, which
in the free ligand is at 3444 cm-1. The CNtBu com-
plexes 24-26 show the νCN band in the 2224-2230 cm-1
region, intermediate between that of the free ligand at
Ack n ow led gm en t. We thank Direccio´n General de
Investigacio´n Cient´ıfica y Te´cnica (Grant No. PB92-
0982-C) and the Fonds der Chemischen Industrie for
financial support. M.-D. A. is grateful to the Ministerio
de Educacio´n y Cultura (Spain) for a grant.
Su p p or tin g In for m a tion Ava ila ble: X-ray crystallo-
graphic files, in CIF format, for compounds 6, 14, 15, 17, and
19 are available on the Internet only. Access information is
given on any current masthead page.
2143 cm-1 and that of [AuCl(CNtBu)] at 2252 cm-1
,
OM970725K
(66) Bellamy, L. J . The Infrared Spectra of Complex Molecules.
Advances in Infrared Group Frequencies; Chapman and Hall: New
York, 1980; Vol. 2.
(67) Maslowsky, E., J r. Vibrational Spectra of Organometallic
Compounds; J ohn Wiley and Sons: New York, 1977.
(68) Nakamoto, K. Infrared and Raman Spectra of Inorganic and
Coordination Compounds 4th ed.; J ohn Wiley and Sons: New York,
1986.