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Bis(1 4 7-trithiacyclononane)gold Dication A Paramagnetic Mononuclear AuII Complex.

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1 H: 3-H). 5.47 (d. 1 H; 1-H). GC-MS (70eV): m / z 328 ( M a , 0.5%), 313 ( M CH,, 22). 282(3), 255(4), 195(12), 167(10), 113(60), lOO(100). [a];" = -77.8
(c = 1.24 in CHCI,). 3h: 'H NMR (300 MHz, CDCI,): 6 = 0.8 (t. ' J = 6.6 Hz,
3 H; 12-H). 1.19-1.70 (m, 24H), 3.07 (m, 1 H ; 5-H), 3.81 (dd, J3,4 = 5.4,
J 4 , 5 = 9.6 Hz, 1 H: 4-H), 4.14 (d, J , , 2 = 2.5 Hz, 1 H ; 2-H), 4.43 (d, 1 H; 3-H),
5.14 (d, 1 H ; I-H). GC-MS (70eV) as for 3g. [a];' = - 50.2 (c = 0.96 in
CHCI,).
Received: September 19, 1989 [Z 3555 IE]
German version: A n g w . Chem. 102 (1990) 228
111 a ) L. Eberson, J. H. P. Utley in M. M. Baizer (Ed.): Organic Electrochemi s t r y 2nd ed., Dekker, New York 1983, p. 435; b) H. J. Schifer, AnZen..
Chem. 93 (1981) 978; Angew. Chem. Int. Ed. EngI. 20 (1981) 911; c) H. J.
Schifer, Top. Curr. Chem. 152 (1990) 91.
[2] S . Torii: Eleclroorganic Syntheses, Methods and Applications, P I . 1 : Oxidations. VCH, Weinheim 1985.
131 a) M Yoshikdwa, T. Kamigauchi, Y. Ikeda, I. Kitagawa, Chem. Pharm.
Bull 29(1981)2571,2582;Heterocyc~estS(1981)349;b)P.G . M. Wuts,C.
Sutherland. Tetrahedron Lett. 23 (1982) 3987.
[4] a) P. Seiler, P. M. Robertson, Chimiu 36 (1982) 305; b) R. Schneider, H. J.
Schifer, unpublished.
[5] H J. Schifer, Kontakte (Dnrmstadt) 1987, No. 2, p. 17.
T, L
/\jIP'/
Fig. 1. ESR spectrum of [A~([9]aneS,),]~' in CH,CN at 77 K.
chemistry, although in this case the tetragonal elongation is
less than in the Au" analogue (Cu-S1 2.419(3), Cu-S4
2.426(3), Cu-S7 2.459(3) A[']).
Bis( 1,4,7-trithiacyclononane)gold Dication :
A Paramagnetic, Mononuclear Au" Complex **
By Alexander J. Blake, John A . Greig, Alan J: Holder,
Timothy I. Hyde, Anne Taylor, and Martin Schroder *
We have shown previously that the potentially six-electron
donor macrocycle [9]aneS, (1,4,7-trithiacyclononane),
which prefers to bind metal ions facially,".21 is capable of
modifying its coordination to accommodate a range of transition-metal stereochemistrie~.~~~
As part of a study of thirdrow transition-metal complexes of [9]aneS3,[3b1 we report
herein the preparation of [Au([9]aneS,)JZ@, the first structurally characterized mononuclear Au" complex.
Reaction of KAuCI, with two molar equivalents of
[9]aneS, in refluxing aqueous HBF,(40 %)/MeOH affords a
reddish brown solution, which was extracted with CH,NO,
after addition of water. The CH,NO, solution was filtered,
the solvent removed in vacuo, and the residue taken up
in CH,CN. Vapor diffusion with diethyl ether afforded
the complex [Au([9]aneS3),J(BF,), in 50% yield. [Au([9]aneS,),]2@ shows characteristic UVjVIS absorption bands
at A,,, = 398(e = 7990),234nm(~= 1 5 0 0 0 ~ - cm-')and
'
a strong signal in the ESR spectrum at g,, = 2.010 (77 K).
Hyperfine coupling to lg7Au ( I = 3/2, 100%) is
observed clearly with A,, = 57.3 G (Fig. 1).
Crystals of [Au([9]aneS3),](BF,), . 2CH,CN suitable for
X-ray diffraction were grown from CH,CN/Et,O. The single-crystal X-ray structure[41of the complex (Fig. 2) confirms unequivocally its assignment as a genuine, mononuclear d9 Au" species: in the centrosymmetric cation, Au" is
bound to six thioether donors in a tetragonally elongated
stereochemistry (Au-S1 2.839(5), Au-S4 2.462(5), Au-S7
2.452(5 ) A). The two [9]aneS, macrocycles therefore encapsulate the d9 Au" center to give a Jahn-Teller-distorted octahedral stereochemistry. Interestingly, the related d9 complex
cation [Cu([9]aneS,),12@ also shows an octahedral stereo[*I
[**I
Dr. A. J. Blake, J. A. Greig, Dr. A. J. Holder, Dr. T. 1. Hyde, A. Taylor.
Dr. M. Schroder
Department of Chemistry, University of Edinburgh
West Mains Road, GB-Edinburgh EH9 355 (Scotland)
We thank the British Science and Engineering Research Council (SERC)
for support and Amersham International PIC and SERC for a CASE
Award to JAG
Angew Chrm. In!. Ed. EngI. 29 (1990) N o . 2
Fig. 2. Structure of the cation [Au([9]aneS,)JZs
[A~([9]aneS,),]~@
is air-stable in the solid state. It can be
reduced in MeOH or more slowly in CH,CN to a colorless
d" Au' species, [Au([9]aneS,),Je (Epc= +O.IOVvs Fc@/
Fc, Fc = ferrocene), and can be oxidized to the corresponding d8 Au"' complex [A~([9]aneS,),]~~
(E, = + 0.46 V vs
=
F C ~ / F C ) . When
[ ~ ~ ' the oxidation of Au" to Au"' (lrnSx
3 3 4 ( ~= 19 765), 246 nm (E= 20265 M-' cm-')) is monitored by UVjVIS spectroscopy, isosbestic points (&, = 372,
208nm) are observed. The chemical synthesis of
[A~([9]aneS~)~]'@
depends on control of these redox reactions. Isolation of the Au" species from electrosynthesis experiments is hampered by problems associated with removing the base electrolyte and purifying the complex.
Very few examples of mononuclear Au" species have been
reported in the literature. Most of these examples are transient or intermediate species or involve significant charge delocalization onto the ligands (e.g., [Au(mnt),Ize, mnt = 2,3dimercapt0-2-butanedinitrile~~~).
The ligand [9]aneS, is redox-inactive up to + 0.99 V (vs Fc@/Fc),['] suggesting that
delocalization of the positive charge in [A~([9]aneS,),]~@
onto the thioether donors will be limited. The coordination
about the Au center in [A~(I9]aneS,),]~@
is fully consistent
with that of a d9 transition-metal center and reflects the
ability of [9]aneS, to encapsulate and stabilize an otherwise
highly reactive metal radical center. Interestingly, we have
found that the hexathia ligand [ISIaneS, is also capable
c.VCH Verlagsgesellschafi mbH. 0.6940
Weinheim. 1990
OS70-0833/90/0202-0197$OZ.SO/O
197
of stabilizing Au’, Au” and Au”’ centers in the complexes
[Au([l 8]aneS,)]@’20’30,respectively.
Received: September 4, 1989 [ Z 3536 IE]
German version: Angen. Chem. 102 (1990) 203
[I] R. S. Glass, W. N. Setzer, C. A. Ogle, G. S. Wilson, Inorg. Chem. 22(1983)
266.
121 K. Wieghardt, H:J. Kuppers, J. Weiss, Inorg. Chem. 24 (1985) 3067; H.-J.
Kuppers, A. Neves, C. Pomp, D. Ventur, K. Wieghardt, B. Nuber, J Weiss,
ibid. 25 (1986) 2400.
[3] a) M. Schroder, Pure Appl. Chem. 60 (1988) 517, and references therein;
M. N. Bell, A. J. Blake, R. 0.Gould, A. J. Holder, T. 1. Hyde, A. J. Lavery,
G. Reid, M. Schroder, J Inclusion Phenom. 5 (1987) 169; b) A. J. Blake,
R. 0 . Gould, J. A. Greig, A. J. Holder, T. I. Hyde, M. Schroder, J. Chem.
Soc. Chem Commun. 1989, 876.
[4] Structure determination of [Au([9]aneS3)J*@. 2BFy . 2CH,CN: An
orange-red column-shaped crystal (0.55 x 0.3 x 0.2 mm), bathed in mother
liquor, was sealed in a Lindemann capillary tube and cooled to 173k 0 . l K
on a Stoe STADI-4 four-circle diffractometer equipped with an Oxford
Cryosystems low-temperature device 161. M , = 813.28, orthorhombic,
space group Pcab, a = 8.6921(13), b = 14.823(3), c = 21.5687(23)A, V =
2779.0 A’ [from 2 0 values of 42 reflections measured at
w(20 =
24-26“,
E.=O.71073A)], T = 1 7 3 K , e,.,,d=l.944gcm-3,
Z=4,
~(Mo,, = 5.781 mm-’, T = 173 K, 0 - 2 0 scans, 2715 reflections measured (20,., = 45‘). 1586 unique (R,,, = 0.022). initial correction for absorption by means of scans, giving 1146 data with F 2 40(F). Intensity
statistics indicated the position of the Au atom on an inversion center and,
using this information, DIRDIF [7] located the S atoms. Iterative rounds of
least-squares refinement and difference Fourier synthesis [8] then located all
other non-H atoms. At isotropic convergence, final corrections for absorption were made using DIFABS [9]. Some disorder in the BFf anion required
modeling. H atoms were included in fixed, calculated positions IS]. At final
convergence, R,R, = 0.0663 and 0.0859, respectively, for 123 parameters,
S = 1.209. The maximum and minimum residues in the final AF syntheses
were + 1.50 and - 1.21 e k ’ respectively. Further details of the crystal
structure investigation are available on request from the Director of the
Cambridge Crystallographic Data Centre, University Chemical Laboratory, Lensfield Road, Cambridge CB2 1 EW (UK), on quoting the full
journal citation.
151 R. J. Puddephatt in G. Wilkinson, R. D. Gillard, J. A. McCleverty (Eds):
Comprehensive Coordination Chemistry, Vol. 5, Pergamon Press. Oxford
1987, chapter 54, p. 861; A. MacCragh, W. S. Koski, J. A m . Chem. Sor. 87
(1965) 2496; J. H. Waters, H. B. Gray, ibid. 87 (1965) 3534; I. F. Warren,
M. F. Hawthorne, ibid. 90 (1968) 4823, J. H. Waters, T. J. Bergendahl, S. R.
Lewis, J. Chem. Soc. Chem. Commun. 1971, 834; R. Kirmse, B. Lorenz, W.
Windsch, E. Hoyer, 2. Anorg. Allg. Chem. 384 (1971) 160; T. J. Bergendahl.
E. M. Bergendahl, Inorg. Chem. I f (1972) 638; R. L. Schlupp, A. H. Maki.
ibid. 13 (1974)44; J. G . M. Rens, M. P. A. Viegers, E. de Boer, Chem. Phys.
Lett. 28 (1974) 104; T. J. Bergendahl, J. H. Waters, Inorg. Chem. 14 (1975)
2556; W. S. Crane, H. Beall, Inorg. Chim. Acta 31 (1978) L469, and references therein.
[6] J. Cosier, A. M. Glazer, J Appl. Cryslallogr. 19 (1986) 105.
171 DIRDIF: P. T. Beurskens, W. P. Bosman, H. M. Doesbury, T. E. M. van
den Hark, P. A. J. Prick, J. H. Noordik, G. Beurskens, R. 0. Gould, V.
Parthasarathia, Applications of Direct Methods to Difference Structure Factors, University of Nijmegen, Netherlands, 1983.
[8] SHELX 76: G. M. Sheldrick, Program for Crystal Structure Delerminations, University o f Cambridge 1976.
[9] DIFABS: N. Walker, D. Stuart, Programfor Empirical Absorption Corrections, Acta Crysrallogr. Sect. A 39 (1983) 158.
in the Fischer-Tropsch reaction or the synthesis of methanol.[’] Since, as end products of such reactions they form
only moderately stable carbonylmetal complexes, they are
seldom investigated as ligands.[’] With the aim of also testing
the soundness of the cluster-surface analogy[31on them with
regard to structure and reactivity we turned our attention to
the cluster chemistry of organic OH-compounds. Here, some
important bond types are known, but also the observation
that one synthesizes Os,(CO),, in alcohol,[51and the comment about Ru,(CO),, , “the corresponding reactions with
alcohols are complex and will be reported later”.[61
Twenty years and one publication”’ later we now find that
the complexation of organic 0x0 compounds with carbonylruthenium compounds can be controlled on a preparative
scale. To demonstrate this, we present the title complex
[H,Ru,(CO),,(p-C,H,O)], which is formed in almost 30%
yield upon heating Ru,(CO),, and an excess of phenol in
boiling cyclohexane.[81
The structure analysis (cf. Fig. 1 [’I) gives a good indication of the course of the reaction: In the first step the oxida-
~
[H,RU,(CO),,(p-C,H,O)] : Binding Of
Five Metal Atoms to a Phenol Molecule””
By D.Scott Bohle, and Heinrich Vahrenkamp*
Alcohols, esters and similar compounds belong to the important products of metal-catalyzed CO hydrogenation, e.g.
[*I Prof. Dr. H. Vahrenkamp, Dr. D. S. Bohle
Institut fur Anorganische und Analytische Chemie der Universitat
Albertstrasse 21, D-7800 Freiburg (FRG)
[**I This work was supported by the Volkswagen Foundation, the Fonds der
Chemischen Industrie, and the Rechenzentrum der Universitat Freiburg.
198
cj VCH b+rlagsgesellschaftmhH, 0-6940 Wemheim, 1990
b
Fig. 1. Structure of [H,Ru,(CO),,(pC,H,O)]
in the crystal (schematic).
tive addition of the phenol could lead to a complex
[Ru,(CO),,(~-H)(~-OR)] which is still recognizable here
in the form of the Rul-Ru2-Ru3-0 unit. The second Ru,unit could then be attacked in the sense of an ortho-metalation at the @-Catom of the
opened by q6-coordination of the phenol ring to Ru4, and condensed to the first
Ru, unit via four new metal-metal bonds (Rul-Ru4, RulRu5, Ru2-Ru5, Ru2-Ru6). This results in a highly puckered
“raft” arrangement“’] of the ruthenium atoms, of which
only Ru3 is not coupled to the phen-yl-olate ligand. Alternatively, the C,H,O-Ru, fragment can be regarded as a doubly
C-metalated derivative of cyclohexadienone, even though
the uniformity of the C-C bond lengths in the ring [139144(1) pm] and the C-0 distance of 136(1) pm, which corresponds to that in the free phenol, do not support this. The
bridging Ru-0 and Ru-C bonds (Rul-0 217(1), Ru2-0
213(1), Ru5-C 234(1), Ru6-C 221(1)pm) of the phen-ylolate ligand lie in the known
however, the asymmetry of the Ru5-C-Ru6 bridge and the very long Ru5-C
distance are striking. The two hydride ligands are presumably over the two longest edges least shielded by CO
groups, namely Ru2-Ru3 (308 pm) and Ru2-Ru5 (31 1 pm);
the remaining Ru-Ru bonds have lengths of 277-304 pm.
The C,H,O ligand counts as a 10-electron donor (6e from
the aromatic x-system, 1 e from the orrho metalation and 3 e
0570-0833/90jl?202-0198 3 02.SO/O
Angen. Chem. Int. Ed. Engl. 29 (1990) No. 2
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complex, paramagnetic, auii, gold, trithiacyclononane, bis, mononuclear, dication
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