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Nonacarbonylbis(3-fluoromethylidyne)triiron Formation of a Biscarbyne Cluster from Carbonyliron and Tribromofluoromethane.

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about 9 p m from the best plane defined by them. The
Ago, groups are linked via common 0-atoms to give a
three-dimensional network structure. From the empirical
formula it essentially follows that 01 and 0 2 thus perform
different topological functions: 0 I with the coordination
number (C.N.) 3 and 0 2 with C.N. 2 referred to silver. The
slight deviations of the Ago4 polyhedron (cf. Fig. 1) from
the ideal D4hpoint symmetry are chiefly due to the different coordinative demands on the oxygen atoms. Consistent
with this, the Ag-02 distance is the shortest, with a value
of 197.6 pm. The average Ag-0 distance of 202 pm is conspicuously close to the corresponding value in the isotypic
AuZ03 (201 pm)I6]. The differences in the bond lengths
within the Ago, group are qualitatively in agreement with
those in Au203. However, the trans-effect discussed in the
case of Auz03 is not noticeable in Agz03.
Nonacarbonylbis(p3-fluoromethylidyne)triiron :
Formation of a Biscarbyne Cluster from
Carbonyliron and Tribromofluoromethane
By Dieter Lentz*, Irene Briidgam, and Hans Hartl
Bismethylidyne complexes, in particular those of cobalt
and of rhodium, have been the subject of intensive investigations in recent years"], not least because of their importance in acetylene cleavage, acetylene metathesis, and the
Fischer-Tropsch process. [(p,-CF)(Co(CO),},J, its derivatives'", and the hetero-clusters obtainable therefrom by
metal exchanger3],were hitherto the only fluoromethylidyne
complexes known. According to the 18-electron rule or the
Wade rules[41a further C F ligand can be incorporated in
the analogous Fe-cluster, which should lead to a trigonalbipyramidal iron-carbon cluster. In contrast to numerous
compounds containing the Co3(CR)' system [Fe3(C0)~(p3CCH3)(k3-COCH,)J was the only known compound containing an Fe3(CR)* moiety['].
Reaction of Fe(CO), or Fe2(C0)9 with CFBr, leads to
formation of 1 (yield 2-3%) as the major component of
the reaction products that are soluble in hexane.
Fe2(C0)9or Fe(CO),
Fig. I . Projection of the Agoa moiety on the best plane defined by oxygen
with bond lengths [pm] and angles ["I.Symmetry-equivalent atoms are indicated in small Roman letters. The Ag-01-Agb angle is 108.7". The shortest
Ag-Ag distance is 304 pm. Maximum standard deviations: 3 pm (bond
lengths) and 0.8" (bond angles).
The existence of Ag203strikingly contrasts with the previously mentioned lack of ternary oxides containing higher
valency silver and emphatically underscores our opinion
that in principle no obstacles, for instance in the chemical
nature of silver, stand in the way of formation of such oxides.
* [Fe3(C0)9(p3-CF)2]1
The trace amounts of byproducts soluble in hexane can be
readily separated by preparative thin-layer chromatography (silica gel, Merck 0.5 mm, hexane). According to its
spectroscopic datar6] 1 is a bis(fluoromethy1idyne) complex. The presence of the isomeric difluoroacetylene complex could be ruled out, in particular by the extreme downfield shift of the I3C-NMR resonance of the carbyne carbon atom (6=365.8, 'JCF=452 Hz). The very large I9F-l3C
coupling constant is indicative of a strong s-part in the C F
bond. The resonance of the CF-group lies at 6=69.5 in a
region unusual for CF-compounds and clearly demonstrates the influence of the metal array on the CF-bond.
According to the X-ray structure analysis"' the two CFligands and the three iron atoms form a trigonal bipyramid
with the CF-ligands in the axial positions (Fig. 1). Three of
the carbonyl ligands are in the Fe3-plane. The remaining
Received: June 25, 1984;
revised: July 20, 1984 [Z 898 IE]
German version: Angew. Chem. 97 (1985) 114
Publication delayed at authors' request
CAS Registry number:
Ag,O,, 12002-97-0.
[I] R. Hoppe, R. Homann, Naturwissenschaften 53 (1966) 501; R.-H. Odenthal, R. Hoppe, ibid. 57 (1970) 305.
[2] In certain cases it has been possible to stabilize higher valence silver in
oxidic systems by complexation; cf., e.g., K5Ag(I050H)2.8H 2 0 : R.
Masse, A. Simon, J . Solid State Chem. 44 (1982) 201.
131 For a survey of the literature on binary silver oxides of the composition
Ag,O, I see: Grnelins Handbuch der anorganischen Chemie, Silber B I ,
Verlag Chemie, Weinheim 1971, p. 102.
[4]I. Naray-Szabo, K. Popp, Z . Anorg. Allg. Chem. 322 (1963) 286; C. H.
Wong, T. H. Lu, C. N. Chen, T. I. Lee, J. Inorg. Nucl. Chem. 34 (1972)
[S] Fdd2; a = 1287.3(8), b = 1047.7(8), c=366.0(4) pm (calculation on 25
Guinier reflections); Z = 8; four-circle Siemens AED2 diffractometer;
M o K ~data
collection at - 2 5 ° C ; 194 independent structure factors 1168
R = 0.076, R , = 0.062. Further details of the crystal strucwith F > 3 ~(01;
ture investigation are available on request from the Fachinformationszentrum Energie Physik Mathematik, D-7514 Eggenstein-Leopoldshafen 2,
o n quoting the depository number CSD 51 151, the names of the authors,
and the full citation of the journal.
(61 P. G. Jones, H. Rumpel, E. Schwarzmann, G. M. Sheldrick, Acra Crystallogr. Secr. 8 3 5 (1979) 1435.
Angew. Chem. Inr. Ed. Engl. 24 (1985) No. 2
Fig. 1. Molecular structure of 1. Important bond lengths [pm] and angles ["I:
Fe-Fe 253.6-254.4(2). Fe-CF 189.4-194.9(4), C-F 135.4(4), Fe-C (in the
Fe3 plane) 178-179(2), Fe-C (above and below the Fe, plane) 182.5187.9(4), Fe. . . C 295-301(2), C - 0 104--116(2); Fe-CF-Fe 82.6-54.0(2),
C-Fe-C 93.0-99.7(3), Fe-C-0 165.0-174.0(10).
[*I Dr. D. Lentz, I. Briidgam, Prof. Dr. H. Hartl
Institut fur Anorganische und Analytische Chemie der Freien Universitat
Fabeckstr. 34-36, D-I000 Berlin 33
0 VCH Verlagsgesellschaji mbH. 0-6940 Weinheim, 1985
0570-0833/85/0202-0119 $ 02.50/0
1 19
CO-ligands are located in pairs above and below the Fe,plane, which forms a mirror plane of the molecule. The
symmetry of the molecule is approximately 3/m (C3h).
The nine CO-ligands are terminal ; carbonyl bridges d o
not occur. Each iron atom is coordinated by a distorted
square-pyramidal array of three CO- and two CF-ligands.
Further CO-ligands, which, because of their large Fe. . . C
distances can no longer be regarded as bound, extend
these arrays to distorted octahedra (Fig. 1). The three
Fe(CO),(CF)* octahedra are coupled via common faces
(inverse Csl 103-structure181)
to give the trinuclear cluster 1
with a common CF-CF edge.
The Fe-cluster occupies two different point positions,
each of population parameter 1/2 and linked via a mirror
plane (Fig. 2). The C O / C F molecular framework in both
arrangements is almost identical; only the positions of the
three carbonyl C-atoms in the Fe3-plane are so different
(distance between C-atom pairs: 52-64(2) pm) that they
can be refined as split atom sites. The two arrangements
are interconvertable by a slight cooperative shift of the Fe
atoms within the octahedron. A disorder of the Fe-triangle
by rotation, as was predicted for Fe3(CO),, on the basis of
solid-state 13C-NMR spectra['] would also appear possible
in this case. However, the small anisotropy of the temperature factors of the Fe atoms and the Mossbauer spectrurn'lo1 make a dynamic disorder below 300 K improbable
in this case. Whether the observed disorder is a random
disorder or concerns domain twins is still unclear.
and [Fe3(CO)12][121
have analogous structural features in the solid state: the Fe,-triangles are arranged statistically in two different positions without
changing the ligand sphere.
Russel in G. Wilkinson: Comprehensive Organometallic Chemistry. Vul.
5. Pergamon, Oxford 1982, p. 162ff, and references cited therein.
[2] W. T. Dent, L. A. Duncanson, R. G. Guy, H. W. Reed, B. L. Shaw, Proc.
Chem. Soc. London 1961. 169: B. R. Penfold, B. H. Robinson, Acc.
Chem. Res. 6 (1973) 73; P. A. Dawson, B. H. Robinson, J . Simpson, J .
Chem. Sue. Dalton Trans. 1979, 1762.
[31 H. Beurich, H. Vahrenkamp, Chem. Ber. 115 (1982) 2385; H. Beurich, R.
Blumhofer, H. Vdhrenkamp, ibrd. 115 (1982) 2409.
[4] K. Wade, Ada. Inorg. Radiochem. 18 (1976) 1.
[51 W:K. Wong, K. W. Chin, G. Wiikinson, A. M. R. Galas, M. ThorntonPett, M. B. Hursthouse, J . Chem. Soc. Dalton Trans. 7983, 1557.
[6] 1: Orange crystals, m.p. 143-144"C, soluble in organic solvents, sublimes at 60"C/10-2 mbar: MS (mass numbers referred to '6Fe): m/z 482
(Me). 454 (MO-CO), 426 (M8-ZCO), 398 (Me-3CO),
342 (MQ-5CO), 314 (Me-6CO), 286 (MO-7CO), 258
( M a - 8 C O ) , 230 (M"-YCO) and further smaller fragments: IR (KBr):
2057 (vs), 2009 (vs), 1989 (vs) (CO), 1166 (m), 1125 (m), 713 (s), 596 (m),
554 (s), 507 (w). 451 (w). 428 (w). 404 (w), 383 (vw) c m - ' ; 1R (n-hexane):
2061 (vs), 2041 (vs), 2004 (s) (CO) cm- ' ; Raman (solid): 98 (vs), I15 (vs),
192 (w). 242 (s), 252 (vs), 419 (s), 427 (m),507 (w), 1975 (w), 1988 (m),
2029 (s), 2038 (5). 2048 (w), 2102 (s) c m - ' ; "F-NMR (CH?CI,, CFCI;
ext.): 6=69.5; "C-NMR (CDCI,, TMS ext.): b'=206.3 (CO, 'J(CF)=5
Hz), 365.8 (CF. 'J(CF)=452 Hz).
[71 1: Cmcm,a= 1101.7(3), b = 1313.2(4), c = 1068.1(4) pm,Z=4:pC,,,=2.07
g c m - 3 ; R=0.031 (MoKn=71.06pm, 945 reflections, 798 with 1 > 2 ~ ( 1 ) ,
absorption correction (k= 29.0 cm I), anisotropic temperature factors,
17 1 refined parameters). Further details of the crystal structure investigation are available on request from the Fachinformationszentrum Energie Physik Mathematik, D-75 14 Eggenstein-Leopoldshafen 2, on quoting the depository number CSD 51 169, the names of the authors. and
full citation of the journal.
[XI A. Simon, E. Westerberg, Angew. Chem. 84 ( 1972) 1190; Anyew. Chem.
Inf.Ed. Engl. 11 (1972) 1105; Z. Anorg. Ally. Chem 428 (1977) 187.
191 H. Dorn, B. H. Hanson, E. Motell, Inurg. Chim. Acta 54 (1981) L71.
[lo] D. Lentz, B. Perscheid, unpublished results.
[ I l l L. T. J . Delbaere, L. J. Kruczynski, D. W. McBride, J . Chem. Soc. Dalton
Trans. 1973. 307.
[I21 C. H. Wei, L. F. Dahl, J. Am. Chem. Soc. 91 (1969) 1351.
Synthesis and structure of
By Giovanni Minghetti*, Albert0 Albinati,
Anna Laura Bandini, and Guido Banditelli
Fig. 2. Disordered structure of 1 ; projection on plane bc. The two partial
structures (dashed and full lines) are interconvertible through the mirror
plane in z = 114.
In the "C-NMR spectrum'61, the carbonyl carbon atoms
give rise to only one triplet, thus indicating that they are
equivalent on the N M R time scale. This is consistent with
a non-rigid structure in solution. Also according to IR
data[61there are no carbonyl bridges present in solution.
Because of the sparing solubility of the compound it was
impossible to carry out low-temperature ',C-NMR measurements for the elucidation of the exchange process.
Several binuclear platinum hydrides [pt,H3(L-L),],
where L-L is a chelating bisphosphane, have previously
been described[']. Complex 1 was shown by X-ray analysis
to contain one terminal and two bridging hydride ligands:
the Pt(p-H),Pt fragment was found by neutron diffraction
to be markedly unsymmetrical'21. The hydrides
[Pt,H,(L-L),]@ react with two-electron ligands such as CO
or C N R to give diplatinum(1) derivatives: in 2, both the
hydrogen atom and the carbonyl group are in bridging positions"].
Here we report the reaction of complex 1 with styrene in
the presence of hydrogen to give the binuclear species 3,
which, to our knowledge[41,is the first compound containing one hydride and one alkylidene ligand bridging two
platinum atoms:
[*] Prof. Dr. G. Minghetti
Received: August 13, 1984;
revised: December 13, 1984 [ Z 964 IE]
German version: Angew. Chem. 97 (1985) 115
[I] A. D. Clauss, J. R. Sharpley, C . N. Wilker, R. Hoffmann, Organome!allies 3 (1984) 619, and references cited therein: R. D. W. Kammitt, D. R.
0 VCH Verlagsgesellschafi mbH. 0-6940 Weinheim. 1985
Istituto di Chimica Analitica e Spettroscopia, Universita di Sassari
Via Vienna 2, 1-07100 Sassari (Italy)
Dr. A. Albinati
Istituto di Chimica Farmaceutica e Tossicologica, Universita di Milano
Viale Abruzri 42, 1-20 100 Milano (Italy)
Dr. A. L. Bandini, Dr. G. Banditelli
Dipartimento di Chimica [norganica e Metallorganica
Universita di Milano
Via Venezian 21, 1-20 133 Milano (Italy)
This work was partially supported by the Minister0 Pubblica lstruzione
0570-0833/85/0202-0120 S 02.50/0
Angew. Chem. Int. Ed. Engl. 24 (1985) Nu. 2
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clusters, formation, biscarbyne, fluoromethylidyne, triiron, tribromofluoromethane, carbonyliron, nonacarbonylbis
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