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Bis(-cyclopentadienyliron- -thiadiborolene)ironЧStructure of a -C5H5 Tetradecker Sandwich Complex.

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a structure the long-range order of which is disrupted, these
sub-unit cell fragments still possess the basic attribute that
confers upon them their exchange capacity and catalytic activity.
Clearly h. r. e. m. can play a useful role in the characterization of microcrystalline and amorphous zeolites, more so perhaps than other solids since the individual units (in this case
the cubo-octahedra) are more readily discernible, and hence
the interpretation of image detail more straightforward.
Received: June 13, 1980 [Z 566 IE]
German version: Angew. Chem. 92, 755 (1980)
CAS Registry numbers:
N o compounds indexed
[ I ] L. A. Bursill, E. A . Lodge, J. M . Thomas, Nature 286, 1 1 1 (1980); J . M. Thomas, G.R. Millward, L. A . Burs;//, Phil. Trans. Roy. Soc., in press; L. A. Burs;//, €. A. Lodge, J. M . Thomas, J . Chem. Soc. Chem. Commun., in press.
[2] J. M. Cowky, Diffraction Physics. North-Holland, Amsterdam 1975.
[3] D.A . Jefferson, G R. Millward, J. M. Thomas, Acta Cryst. A 32, 823 (1976);
J. M. Thomas, D.A. Jefferson, Endeavour (New Series) 2. 127 (1978).
141 R. M. Bower, Zeolites and Clay Minerals as Sorbents and Catalysts. Academic Press, New York 1978.
Bis(rl-cyclopentadienyliron-~,q-thiadiborolene)ironStructure of a q-C5H5Tetradecker Sandwich
By Walter Siebert, Christian Bohle, and Carl Kriiger[*l
the compound [(C5HS)Fe(C8H,2)]2Zn,
recently described by
Jonas et
with 1,2,5-thiadiborolene to give the trinuclear
complex (1) (58% yield) we have now found a route for the
synthesis of the long-sought sandwich anion (2)f41.We report
tetrahere on the first 9-cyclopentadienyl-p-thiadiborolene
decker sandwich complexes (4) and (5) which we obtained in
53 and 42% yield, respectively, from the anion (2) and FeC12
and CoCl2.
Direct reaction of ( I ) with C0C12 leads, as a result of ligand exchanges, to (C5Hs)Co(C2B2S)(83%), (C5H&Fe (70%)
and traces of (3). Reaction of (1) with FeCI2 in boiling tetrahydrofuran (THF) affords besides (3) and (4) (19%) the hydride complex [(C,H,)Fe(H) (C2B2S)], which contains a
3z/2e bond [6"B(CS2)=0.3 (br. s, I), 34.7 (s, l)].
This compound is also obtained on reaction of ( I ) with HClgas; the isomeric hydride complex [(C5H5)(C2B2S)Fe-H]
[G1'B(CS2)=25.3(s, 1), 38.7 (s, 1); 6'H(CS2)= -7.4 (Fe-H)]
is formed initially and is then converted thermally into the
compound with the Fe-H-B
The constitution of (4) follows from the spectroscopic data
[6'H(CS2)=3.52 (s, lo), 3.1 (m, 4), 1.9 (rn,4), 1.79 (s, 12),
1.22 (t, 12); 6"B(CS2)= 19.2; MS: m/e=630 ( M + , 100%)(70
eV)]. The "B signal indicates four equivalent boron atoms as
well as bifacial coordination of the thiadiborolene ligands.
The B-CH3 signal is consistent with a trans arrangement of
the p-ligands, which, as for the trinuclear complexes
and [(C2B2S)Co(C2B2S)]2Fe1'1,
confirmed by the crystal structure analysis['] (Fig. 1).
Dedicated to Professor Karl Dimroth on the occasion of
his 70th birthday
Triple-decker complexes with terminal carbon monoxide
or thiaborolene ligands are cleaved by cyclopentadienide
into anionic mononuclear compounds which form tetradecker complexes with transition-metal halides'']. An analogous
cleavage of the q-cyclopentadienyl triple-decker sandwich
(3)l2] fails because of its short Fe.. .Fe distance. By reacting
9 -B,
Fig I . Molecular structure of the complex (4) in the crystal
[*] Prof. Dr W. Siebert, Dr. C. Bohle
Fachbereich Chemie der Universitat
Hans-Meerwein-Strasse, D-3550 Marburg 1 (Germany)
Present addressAnorganisch-Chemisches Institut der Universitat
Im Neuenheimer Feld 270
D-6900 Heidelberg 1 (Germany)
Priv.-Doz. Dr C. Kruger
Max-Planck-lnstitut fur Kohlenforschung
Lembkestrasse 5 . D-4330 Mulheim-Ruhr 1 (Germany)
[**I Tetradecker Complexes, Part 3. This work was supported by the Deutsche
Forschungsgemeinschaft and the Fonds der Chemischen Industrk-Part 2: [r].
0 Verlag Chemie, GmbH, 6940 Weinherm, 1980
The distances between the ring atoms in the fi-ligands
are C-C= 1.461(3), B-C= 1.564(3), 1.556(3) and
1.913(2) A, and in the 9-ligands
C-C= 1.405(4)-1.417(4) A. Fel ocFupies an inversion center, the Fel-Fe2 distance (3.272(1) A) is only slightly longer
than in (3) (3.236(1) A).
The distances between the metal atoms and the best
planes of
the ligands (D) [Fe-D(C,H,) = 1.67,
Fe-D(C,B,S) = 1.63, and Fel-D(C,B,S) = 1.64 A] are similar. I? contrast, strongly deviating distances (1.69, 1.60, and
1.93 A) were found in the tetradecker sandwich complex
Angew. Chem. Int Ed. Engl 19 (1980) No. 9
[(C2B2S)Co(CZBzS)JzFe(6)f’I.The different influence of
the d7 fragments (C5H5)Fe and (C2B2S)Co on the
(C2B2S)Fe(CzBzS)unit is manifested in the expansion of the
central sandwich from 3.28 in (4)to 3.86 A in (6); the expansion reflects the enhanced acceptor character of the terminal
thiadiborolene ligands. Consequently, there are no drastic
changes in the ligand/metal bonding relationships on incorporation of the 12-valence-electron “stack” [(C,B2S)Fe] into
the tripledecker (3) to give the tetradecker (4).Therefore
complexes with n > 2 should
also be stable.
(4),with a (4 x m6+ 3 x d6) arrangement, is the parent
member of the series of tetradecker sandwich complexes (42
to 48 valence electrons). The cobalt compound (5) with a total of 43 valence electrons is accordingly paramagnetic and
has an 8-line ESR spectrum ((g) =2.087, u(59C0)=45, 2G).
(1): A mixture of [(C5H5)Fe(COD)],Znf3](1.9 g, 3.63
mmol) and 3,4-diethyl-2,5-dimethyl-1,2,5-thiadiborolene
(1.9 g, 11.4 mmol) in n-hexane (25 ml) is heated under reflux
for 1 h. After filtration through a frit the solution is concentrated by evaporation to 10 ml and cooled to -78 “C. The
red crystals which are formed are washed with ether and
dried in a high vacuum. Yield 1.35 g (1) (58%); m.p. 182184°C; 6”B(CS2)=14.6; MS: m/e=639 ( M + , 15%).
(4):A solution of (1) (0.95 g, 1.49 mmol) in THF (25 ml) is
allowed to react with mirror potassium (0.22 g, 5.64 mmol)
for 64 h. Excess potassium is separated off and the solution
treated with 0.4 g (1.49 mmol) FeClZ.2THF.After 16 hours’
stirring and removal of THF, the residue is taken up in toluene (20 ml), filtered, evaporated down to 5 ml, and allowed
to stand for 16 h at -78°C. Yield 0.5 g (53%) (4) as black
needles, m.p. 209-211 “ C (dec.). (5) is obtained analogously
(0.4 g, 42%): m.p. 218 “ C (dec.).
Received April 18, 1980 [ Z 567 IE]
German version. Angew Chem 92, 758 (1980)
[ I ] W. Siebert, W. Roihermel, C. Bohle. C Kniger, Y.-H. Tsay, D. J. Brauer, Angew. Chem. 91, 1014 (1979); Angew. Chern. Int. Ed. Engl. 18, 949 (1979).
121 W. Rothermel, Dissertation, Universitat Marburg 1979.
131 K. Jonas, L. Schieferstein, Angew. Chern. 91, 590 (1979); Angew. Chem. In!.
Ed. Engl. 18, 549 (1979); K. Jonas, L. Schieferssrein, C. Kriiger, Y:H. Tsay.
ibid. 91, 590 (1979) and 18, 550 (1979).
[4] C. Bohle, Dissertation, Universitat Marburg 1980.
IS] W Siebert. C. Bohle. C. Kriiger. Y.-H. Tsay. Angew. Chem. 90, 558 (1978):
Angew. Chem. Int. Ed. Engl. 17, 527 (1978).
[6] Crystallographic data:
c = 10.973(1)
a=95.978(6), p=97.938(6), y = 112.674(8)”. Space group Pi. Z = 1, 4076 reflections, 457 unobserved (2u); R=0.034 (R,=0.040).
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tetradecker, complex, thiadiborolene, ironчstructure, bis, sandwich, cyclopentadienyl, c5h5
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