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First Coupling of a Metal Atom with Four Ethene Molecules to give a Metallaspiroalkane.

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First Coupling of a Metal Atom with Four Ethene
Molecules to give a Metallaspiroalkane**
By Klaus Jonas,* Giinter Burkart, Christian Haselhojf;
Peter Betz, and Curl Kriiger
2 LiCp
+ I C,,H, + [Li(thf),][Mn(r14-Ci,H,)(PMe,),]
Dedicated to Professor Giinther Wilke on the occasion of his
65th birthday
Up to now, only a few examples of transition metal complexes with more than two ethene ligands are known. Tris(ethene)nickel(o),['' the first homoleptic transition-metalethene-complex, was reported in 1973, and two years later
Stone et al. described the analogous platinum compound
2.['1 There are only the iridium compound 313]and the alkali
metal-transition metal complexes 4 and 5 containing one
more ethene ligand. 4 and 5 are accessible from cobaltocene
and ferrocene, respectively, by reductive five-membered ring
ligand removal[41.
other two are occupied by an q4-coordinated naphthalene
We intended to convert complex 6, which is obtained in
THF solution according to equation (a), to a more thermally
stable manganate. Decisive for the success of the synthesis of
the novel potassium manganese compound 8 from 6, ethene
and pyridine [Eq. (c)] was the observation that the color of
the ethene-saturated THF solution of 6 changes from red to
brownish-yellow on warming to - 35 "C. Orange 8 is isolated if pyridine is added and the solution subsequently warmed
to room temperature (yield: 68 YO).
6 in T H F (ethene) .-
First findings on the reactivity of ethene towards low-valent manganese have already been briefly reported in a review article.[41In the case of the reaction of manganese(r1)
cyclopentadienide (Cp,Mn) with naphthalenepotassium
(molecular ratio 1 :3) in ethene-saturated tetrahydrofuran
(THF) mentioned therein, we have now found that exactly 3
moles of C,H, are taken up per mole of Mn at - 65 "C. All
the Cp precipitates as KCp, and the markedly therrnotabile
manganese compound 6, which must contain potassium and
manganese in the molar ratio 1 :1, remains in solution
[Eq. (a)]. As yet we have been unable to isolate and fully
characterize 6. Consequently, it is also still an open question
whether the manganese in 6 is present as manganese(-1) (with
three .n-bound ethene molecules) or whether the oxidation
state of the manganese increases with uptake of the ethene (6
as a metallacy~lopentane[~.
5l or as a hydridovinyl compound[61).
+ 3 K[C,,H,] + 3 C,H4
In the solid state, 8 contains two crystallographically independent ion pairs. Figure 1 shows both pairs in comparable
orientation. With almost identical bond lengths they differ in
-65 'C
Fig. 1. Structure of 8 in the crystal (two crystallographically independent ion
pairs. see text). P2,/a, a = 17.092(8), h = 15.482(6), c = 17.959(6)
/3=108.32(3)", V=45114A3, T = -173°C. 2 = 8 , ~,,,,,=1.31gcm~',
= 0.71069 A, p = 7.59cm-', R = 0.052. R , = 0.045. 13127 independent reflections, 8538 observed (0> 2a(l)), 505 refined parameters, residual electron
density 0.51 e k 3 . Hydrogen atoms localized, but not refined [13].
When Cp,Mn is reduced with naphthalenelithium (again
in the ratio 1:3) and the ethene is replaced by trimethylphosphane [Eq. (b)], then, after substitution of the tetrahydrofuran bound to lithium by tetramethylethylenediamine
(TMEDA), the novel manganese(-I) compound 7, which is
stable at room temperature, can be isolated (yield: 65%).
According to an X-ray structure analysis of the diamagnetic complex 7,")three coordination sites of the pentacoordinated manganese are occupied by PMe, ligands, while the
Prof. Dr. K. Jonas. Dr. G. Burkart, Dip1 -Chem C. Hiselhoff,
DJ P. Betz [+I, Pror. Dr C. Kruger 1'1
Max-Planck-Instltut fur Kohlenforschung
Kaiser-Wilhelm-Platz 1, D-4330 Miilheim a. d. Ruhr (FRG)
Crystal structure analysis.
This work was supported by the Deutsche Forschungsgemeinschaft
(stipendium for P.B.)
mhH. 0-6940 Wemheim. 1990
the orientation of the pyridine ligands, both at the distorted
square-pyramidally coordinated manganese atom as well as
at the potassium. In the unit cell the latter forms ion pair
contacts of unequal length to the butanediyl ligands of
adjacent anions (K-C, 3.09- 3.33 A). Correspondingly, the
arrangements of the pyridine ligands bound to potassium
(N-K(av) 2.787(3) A) are not linear; the N-K-N angle is
139.0(1) and 147.0(1)", respectively. The C-C bond lengths
and the angles of the C,H, ligands correspond within the
limits of error to the values expected for C(sp3)-C(sp3)
bonds. The average Mn-N distance is 2.354(2) A, while the
average Mn-C(sp3) distance is 2.128(10) A.
nS70-0R3319010303-3-0322S OZ.SOl0
Angen. Chem. Int. Ed Engl. 29 (1990) N o . 3
The synthesis and elucidation of the structure of 8 confirm
once again that ring closure reactions of metal atoms with
ethene to give metallacyclopentanes are to be expected, especially of the transition elements on the left of the 8th subgroup in the periodic
*] That butanediyl ligands
formed by the coupling of two ethene molecules can also
occupy bridge positions was first demonstrated with the dinuclear complex CpV(p-C,H,),VCp.[91 Here we report on
the new finding in metallacyclic chemistry['*. '1 that the ring
closure with ethene leading to formation of a five-membered
ring can also take place twice at a metal atom. The result is
a metallaspirononane in which the transition metal functions
as spiroatom.
A THF-solution of naphthalenelithium (prepared from lithium (0.6 g.
86.5 mmol). naphthalene (10.98 g, 85.7 mmol) and T H F (150 mL) at - 15 "C)
was treated with 10 mL (ca. 100 mmol) of PMe, a t -78 "C and then with 5.28 g
(28.5 mmol) of solid Cp,Mn. After 1.5 hours' stirring at -78 "C, the mixture
was allowed to warm to room temperature, and the raulting deep-red solution
was evaporated to dryness; uncomplexed naphthalene was then removed by
sublimation (20'C. high vacuum). The residue remaining was taken up in
250 mL of Et,O, filtered to remove LiCp, and the filtrate treated with 20 mL of
TMEDA. On cooling to -3O'C. dark-red crystals of 7 separated out; these
were washed with a little ether at - 78 "C and dried in vacuo (oil-pump) a t 20 "C
(yield 12.10 g, 65%). Correct elemental analysis.
8: A solution of naphthalene (18.25 g, 142.4 mmol) in T H F (400 mL) was
treated with 5.63 g (144.0 mmol) of potassium pellets [12] and the mixture
stirred for 1.5 h at - 15'C. Following subsequent cooling to -65°C. saturation with ethene, and addition of solid Cp,Mn (8.87 g, 47.9 mmol) the mixture
was stirred under a n atmosphere of ethene for a further 16 h and allowed to
warm to -35'C within 8 h. After a further 16 h at - 7 8 ° C the KCp that
separated out was removed by filtration, the filtrate treated with 15 mL
(186.2 mmol) of pyridine and the mixture warmed to 20 'C. After evaporation
to dryness, the naphthalene was removed a t 20 "C by sublimation in vacuo. The
residue was then taken up in 400 mL ofether, filtered, and the filtrate evaporated down in V ~ C U Ountil 8 began to separate. By warming to 30 "C. 8 was brought
into complete solution again and the solution stored at - 30 'C. 8 separated as
brownish-orange crystals. The crystals were washed with pentane and dried at
20°C in vacuo (oil-pump). Yield: 14.45 g, 68%; correct elemental analysis.
Received: August 31, 1989 [Z 3531 IE]
German version: Angen. Chem. 102 (1990) 291
CAS Registry numbers:
7, 125281-25-6; 8. 125281-27-8; Cp,Mn, 73138-26-8
[I] K . Fischer, K. Jonas, G. Wilke, Angen. Chem. RS (1973) 620; Angcw.
Chem. I n / . Ed. Engl. 12 (1973) 565.
121 M. Green, J. A. K. Howard, J. L. Spencer, F. G. A. Stone, J Chem. SJC.
Chem. Commun 1975, 3; Dalron Truns. 1977, 271.
[3] A L. Onderdelinden, A. van der Ent. Inorg. Chim. Acru 6 (1972) 420.
141 K. Jonas, Angew. Chem. 97 (1985) 292, Angerv. Chem. In[. Ed. EngI. 24
(1985) 295, and references cited therein.
[5] G. Erker, U . Dorf, A. L. Rheingold, Orgunome/allics 7 (1988) 138, and
references cited therein.
[6] C. K. Ghosh, J. K. Hoyano, R. Krentz. W. A. G. Graham, J Am. Chem.
Soc. l l f (1989) 5480, and references cited therein.
[7] Disorder in the region of the TMEDA moiety of the cation precluded a
detailed discussion of the molecular geometry of 7. P2,/c, u = 9.249(2),
h = 27.715(8), c = 15.311(3) A, [j = 101.84(1)". Z = 4. R = 0.094.
R , = 0.089. 8623 independent reflections [13].
[8] M. L. Steigerwald, W. A. Goddard 111, J. Am. Chem. SOC.107(1985) 5027.
[9] K. Jonas, W. Russeler, C. Kriiger, E. Raabe, Angew. Chem. YX (1986) 902;
Angew. Chrm. Inr. Ed. Engl. 25 (1986) 925.
[lo] a) G. Wilke, Angen. Chem. 100 (1988) 189; Angen. Chem. In/. Ed. EngI. 27
(1988) 185. and references cited therein. b) G. Wilke, Pure Appl. Chun SO
(1978) 677, and references cited therein.
[ I l l S . D. Chapell, D. J. Cole-Hamilton, Polyhedron I (1982) 739.
[12] K . Jonas, E. Deffense. D. Habermann, Angeir.. Chem. 95 (1983) 729;
Angen. Chem. In?. Ed. EngI. 22 (1983) 716; Angew. Chem. Suppl. 19x3.
[13] Further details of the crystal structure analyses are available on request
from the Fachinformationszentrum Karlsruhe. Gesellschaft fur wissenschaftlich-technische Information mbH, D-7514 Eggenstein-Leopoldshafen 2 (FRG), on quoting the depository number CSD-54065, the names
of the authors, and the journal citation.
Supramolekulare Chemie. By E Vogtle. Teubner, Stuttgart
1989. 447 pp., paperback, DM 42.00. - ISBN 3-51903502-2
This book meets a need arising from the growth of interest
in supramolecular chemistry, especially since the award of a
Nobel Prize to Pedersen, Lehn and Cram for their work in the
area. The twelve chapters (whose lengths vary from six to
135 pages) describe both older and more recent aspects of
supramolecular chemistry. Molecular recognition mechanisms of a purely biochemical nature are not included, nor
Angeu. Chrm. I n [ . Ed. EngI. 29 (1990) No. 3
are membrane and polymer chemistry. Instead the book concentrates mainly on the now almost classical chemistry of the
complexation of charged and uncharged guest molecules by
host molecules of widely differing structures. In addition,
however, it contains separate chapters on liquid crystals and
inclusion complexes in the solid state. These are followed by
chapters on organic switches, organic conductors, molecular
electronics and the light-induced decomposition of water,
which indicate future perspectives in supramolecular chemistry.
Following an introductory chapter, host molecules for
cations and anions are described (Chapter 2). Here, after a
thorough treatment of bipyridyl-containing molecules, Section 2.2 discusses in detail the differences and common features of various open-chain podands, macrocyclic coronands
and macrobicyclic cryptands, and describes the wide variety
of molecules and applications (e.g., in phase transfer catalysis or in analysis). In the chapter on podands, however, it is
surprising that the EDTA molecule is not included. After a
detailed treatment of iron-complexing siderophores and descriptions of some cyclophane complexes (metal ion complexes; the neutral complexes of cyclophanes are treated in
Chapter 4), this chapter concludes with the catenanes.
The separation of Chapters 3 and 4, on bioinorganic and
bioorganic model compounds, from Chapter 2 seems rather
arbitrary. In these two chapters host-guest complexes are
VCH Yerlagsgesellschafi mbH. 0-6940 Weinheim. f 990
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ethene, first, metali, couplings, atom, four, molecules, give, metallaspiroalkane
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