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Na10{Li2[MnO4]4} a Compound in Which LiO4 and MnO4 Tetrahedra Form Chains Consisting of Six- and Eight-Membered Rings.

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Na,,(Li,[MnO,],), a Compound in Which LiO,
and MnO, Tetrahedra Form Chains Consisting
of Six- and Eight-Membered Rings **
By Dieter Fischer and Rudolf Hoppe *
2
Little is known about the structure of oxides of the type
A,[MO,] with A = K, Rb, Cs and M = Pv, AsV,Vv, CrV,
MnV.In all single crystals so far obtained, the [MO,] structural unit exhibits disorder. This situation abruptly changes
when derivatives such as K,(Li[VO,]) [‘I and Cs,{Li[VO,]}
are synthesized. In these “lithovanadates”, the linkage
of [MO,] and [LiO,] groups ensures an ordered structure. An especially important example of this kind is
K, 1{Li[OMn0,],),[31 which contains an anion not found so
far for pentaphosphates, for example. Upon attempting
to prepare Na,{Li[Mn0,]),f41 we surprisingly obtained
Na,,{ Li,[MnO,],), which has an unexpected structure.
The structure determination [51 afforded the motifs of mutual adj~nction[’~
and distances given in Table 1. Included
are the “naive” coordination numbers (C. N.) and the effective coordination numbers ( E C O N ) . -~ 91
~
Table 1. Na,,{Li,[MnO,],}:
Atom
101
Fig. 1. Section of the Li-Mn-0 chains along [OlOl in Na,,{Li,[MnO,],}; the
oxygen atoms are drawn as thermal ellipsoids (ORTEP at 50% probability).
consist of alternating six- and eight-membered rings. The
lie
eight-membered rings, {Li[0,,2Mn(0,,,)Ol,,J,Li),
roughly parallel to (001). The six-membered rings,
{ Li[O lizMn(02,1)0
1,2][0
,,,(MnO,, ,)]Li}, are oriented parallel to (100). The chains are linked through Na+ ions.
The structure of the chainlike anion {Li,[MnO,],} l o - ,
formed from two kinds of rings, is even more bizarre than
motifs of mutual adjunction. distances [pm], naive coordination numbers (C. N.), and effective coordination numbers (ECoN).
202
203
104
205
206
2 01
10 8
209
1010
C.N.
ECoN
[a. c1
2 Li
112
191.4
111
191.0
111
195.6
1 Mnl
211
169.4
ill
110.2
2 Mn2
1 Mn3
111
168.4
2 Nal
2 Na2
2 Na3
112
236.4
1 Na4
2 Na5
111
305.1
252.8
111
255.1
111
242.2
111
234.1
211
241.4
211
261.5
111
241.4
1 Na6
111
236.1
C N.
ECoN [b, c]
6
5.0
111
229.0
111
259.7
111
230.2
111
291.6
111
246.0
5
4.1
5
4.1
4
4.0
4
4.0
6
S f l
6
5.0
6
5.8
I
6.2
1i2
244.4
7
5.5
211
283.1
111
230.3
5
3 f 2
3.7
5
4.4
6
4.8
111
248.9
1:2
264.4
Ti1
231.5
111
111
262.5 286.5
6
4.6
5
4.5
112
289.6
111
231.6
112
244.4
131
236.2
6
5.6
4.0
111
168.9
211
170.0
111
241.3
111
241.4
111
215.3
4
111
170.9
111
170.5
111
234.8
Ill
111
241.1 210.3
111
241.4
4.0
193.2
111
170.1
111
172.2
1/1
110.4
4
111
5
4.1
6
5.5
50
~~~~~
[a] Cations/XO. [b] OjX cations. [c] Starting values for the ionic radii: ionic radii with r ( 0 2 e ) = 140 pm were derived from the averaged distances weighted according
to the ECoN concept.
Primary structure: Lithium and manganese are surrounded in a tetrahedral fashion by 0 (distances: Li-0, 191.0195.6 pm; Mn-0, 168.4-172.2 pm). The coordination
spheres of the N a + ions are irregular; the naive coordination
numbers are 5-7.
Secondary and tertiary structure: The structure is characterized by unusual chains along [OlO] (Fig. 1). The chains
Prof. Dr. R. Hoppe, Dip1.-Chem. D. Fischer
Institut fur Anorgdnische und Analytische Chemie I der Universitat
Heinrich-Buff-Ring 58, D-6300 Giessen (FRG)
[**I Taken from the Dissertation of D. Fischer, Universitat Giessen. This work
was supported by the Deutsche Forschungsgemeinschaft and the Fonds
der Chemischen Industrie.
[*]
800
XJ
VCH Verlagsge.se~lschu~
mhH, 0-6940 Weinheim, 1990
those of the many other intriguing anions we have so far
obtained during the synthesis of new oxides of alkali metals.
We have found mono- and multinuclear anions such as
those in K,[O-Ni-O][’o] (analogous to XeF,[“l), in
K,[Zn03],[’2r and in Na,[FeO,],[’ 31 with structural units
analogous to C0:O. Furthermore, we have found compounds containing two-tetrahedra units, for example,
K,[0,Fe02Fe0,],[’41 three-octahedra units, for example,
K,Li,,[M,O,,] with M = Pb,[‘51 Zr,[161 Tb,[I7] and fourtriangle units (Nalo[Co,09]).r181 Ring-shaped anions are
present in oxides such as K,[Cu,O,],
Na,[Ag,0,],[’91
and CS,[AU,O,],[~~~zigzag chains in CS[CUO,/,],[~’~
“Zweier-Einfach-Tetraederketten”,
for
example
in
K2Na,[(Fe03)2J>221
“Vierer-Einfachketten” of this kind in
0570-0833/90/0707-0800 8 03.50+.25/0
Angew. Chem. Int. Ed. Engl. 29 (1990) No. 7
[26] D. Schuld, R. Hoppe. 2. Anorg. A / & . Chem., in press.
C S , N ~ , ~ [ ( G ~ O , ) , ] ,and
[ ' ~ ~mixed chains consisting of tetra[27] R. Hoppe, J. Birx, 2. Anorg. Allg Chem. 557 (1988) 171
hedra and squares in Rb5[0,,,Si0,Li0,Si0,Ni0,,,] .Iz4] A
1281 H.-P. Miiller, R. Hoppe, 2. Anorg. Allg. Chem. 569 (1989) 16.
unique kind of chain is present in K,Be,O,, in which planar
[29] G. Brachtel, R. Hoppe, Nulurwi.ysenschu/ien 64 (1977) 271.
triple coordination and tetrahedral coordination alternate
[30] G . Brachtel, R. Hoppe, Angew. Chem. 8 9 (1977) 45: Angew. Chem. lnt. Ed.
according to the formula ~[0,,2Be[310Be[310,,2Be131];[251Engl. 16 (1977) 43.
1311 R. Hoppe, Angew. Chem. 78 (1966) 52: Angen,. Chem. I n t . Ed. Engl. 5
that is, the "butterfly motif" of oxides such as
(1966) 95; ibid. 82 (1970) 7 and 9 (1970) 25.
K,Na,[O,MOMO,] with M = Be,[261CO>'~]and Fe[281(in
[32] J. Kissel, R. Hoppe. Z . Anorg. AIIg. Chem., in press.
Cs,K,[Fe,O,]) is combined with BeO, tetrahedra. In addition, there are layer structures (Na,[Fe,05][291) and framework structures such as KGaO, .123J
However, chains consisting of rings are rare for such oxides. So far, we have found only one other example,
Na,,[Fe,O,,], in which twelve- and eight-membered rings
Highly Selective Synthesis of (E)-Alkene Isosteric
made up of Fe and 0 alternate.[301{Li,[MnO,],}'o-, conDipeptides With High OpticaI Purity via
sisting of alternating cyclohexane- and cyclooctane-like
RCu(CN)Li BF, Mediated
rings, is much more complicated, since [Mn0,I3- groups are
Reaction **
involved in the structure.
The Madelung Part of Lattice Energy
was
By Toshiro Ibuka,* Hiromu Habashita, Susumu Funakoshi,
calculated and a value of MAPLE(Mn,O,) = 9694 kcdl
Nobutaka Fujii,* Yusaku Oguchi, Tadao Uyehara,
mol-' was obtained. This value is in good agreement
and Yoshinori Yamamoto *
(-0.2%) with the MAPLE values for Mn,O, from the
K , (Li[OMnO,],) structure determinati~n[~I
and for V,O,
The concept of replacing the scissile C-N unit of a peptide
from the orthovanadates(v) (A,LiVO, with A = K, Rb,
bond in enzyme substrates by suitable isosteric units that
C S " . ~and
] Rb,V,0,1321).
could provide potential protease inhibitors has drawn a lot
of attention in recent years."' Thus, it has been suggested
that replacement of the arnide bond (-CO-NH-) of a peptide
Received: January 26, 1990 [Z 3762 IEj
1 by an (E)-double bond might provide "(E)-CH=CH
German version: Angew. Chem. 102 (1990) 835
isosteres" 2 possessing high lipophilicity as well as enhanced
resistance to biodegradation.[']
-
J. Kissel. R. Hoppe, 2. Anorg. Allg. Chem. 750 (1989) 109-118.
J. Kissel, R. Hoppe, 2. Anorg. ANg. Chem. 751 (1989) 113-126.
D. Fischer, R. Hoppe, 2. Anorg. Allg. Chem., in press.
The preparation was carried out by annealing thoroughly mixed amounts
of Na,O, and LiMnO, (Na:Mn =2.8:1) in Ag bombs (SSOT, 30d).
Both the starting materials and the product were handled under dry argon.
[5] Crystal data: Na,,{Li,[MnO,],}
crystallizes orthorhombically, space
group Pnmu (No. 62) with a = 1048.1(7), b = 1518.4(9),c = 1044.4(6) pm
(diffractometer data), 2 = 16, p(MoK.) = 31.4cm-'. 2469 unique reflections (3" I 0 I 30") were measured (Siemens AED 2 four-circle diffractometer with Mo,, radiation, graphite monochromator); absorption correction. The structure was solved by the use of direct methods in
conjunction with difference Fourier syntheses (SHELX-76 and -86)[6].
The subsequent refinement of the parameters, carried out with "anisotropic" temperature factors (least-squares method), gave R = 8.6%, R, =
3.6% ( w = 0.5451 u-, (Fa)for 2450 reflections; goodness of fit = [Xw(F,~'),/(N"~~~""~-N~=
~ ~1.138.
* ~ ~ ,Further
= , ~ ) ] 'details
',
of the crystal structure investigation may be obtained from the Fachinformationszentrum
Karlsruhe, Gesellschaft fur wissenschaftlich-technischeInformation mbH,
D-7514 Eggenstein-Leopoldshafen 2 (FRG), on quoting the depository
number CSD-54425, the names of the authors, and the journal citation.
161 G. Sheldrick, SHELX-76 and SHELXS-86 Progrummsysrem, Cambridge
University, England, and Universitdt Gottingen, FRG.
[7] R. Hoppe, Angew. Ckem. 92 (1980) 106; Angew. Chem. I n l . Ed. Engl. 19
(1980) 110.
[8] G. Meyer, R. Hoppe, 2. Anorg. Allg. Chem. 420 (1976) 40.
191 R. Hoppe, %. Kristallogr. 150 (1979) 23.
[lo] H. Rieck, R. Hoppe, 2. Anorg. Allg. Chem. 400 (1973) 311
[ l l ] R. Hoppe. Angew. Chem. 76 (1964) 455; Angew. Ckem. Inr. Ed. EngI. 3
(1964) 532.
[12] R. Baier, R. Hoppe. 2. Anorg. Allg. Chem. 546 (1987) 122.
[13] H.Rieck, R. Hoppe, Nufurwissenschuften 61 (1974) 126.
[14] H.Rieck, R. Hoppe, Angew. Ckem. 85 (1973) 589; Angew. Chem. Inl. Ed.
Engl. 12 (1973) 673.
I151 B. Braze], R. Hoppe, 2. Anorg. Allg. Ckem. 493 (1982) 93.
[16] R. Werthmann, R. Hoppe, 2. Anorg. ANg. Chem. in press.
[I71 R. Wolf, R. Hoppe, 2. Anorg. Allg. Chem. 539 (1985) 39.
[18] B. Burow, R. Hoppe, 2. Anorg. Allg. Chem. 467(1980) 158.
[19] W.Losert, R. Hoppe, 2.Anorg. Allg. Chem. 524 (1985) 7.
[20] H.D. Wasel-Nielen, R. Hoppe, 2. Anorg. Allg. Chem. 359 (1968) 36.
[21] H. Klassen, R. Hoppe, Z. Anorg. Allg. Chem. 497 (1983) 70.
[22] K. Mader, Diplomarbeif, Universitat Giessen 1990.
[23] H:P. Muller, Di.yserlation, Universitat Giessen 1990.
[24] R. Hofmann, R. Hoppe, Z . Anorg. Allg. Chem. S69 (1989) 31
[25] D. Schuld. R. Hoppe, 2. Anorg. Aflg. Chem., in press.
[l]
[2]
[3]
[4]
Angew. Chem. l n t . Ed. Engl. 29 (1990) No. 7
0 VCH
The (E)-CH=CH- bonding in 2 closely resembles the
three-dimensional shape (rigidity, bond angle, and bond
length) of the parent amide l.[,]Except in a few cases,I4I
however, published synthetic routes to such peptide mimics
give unsatisfactory results with regard to double bond geometry and/or stereochemistry at the a-position.IS1For example, the reaction of cr,&unsaturated esters with lithium diisopropylamide (LDA) followed by alkyl halides gave, as one
might expect, both a-alkylation isomers and a dialkylated
by-product.[61Clearly, development of an efficient synthetic
route to compounds of type 2 would be extremely valuable.
We now report another solution, based on the 1,3-chirality
transfer reaction of y-mesyloxy-a,p-enoates, to the problem
of controlling the double bond geometry at the P,y-position
and the stereochemistry of the chiral carbon center at the
a-position. The requisite y-mesyloxy-(E)-a,p-enoates (3, 5,
[*I Associate Prof. Dr. T. Ibuka, Prof. Dr. N. Fujii, H. Habashita, Associate
Prof. Dr. S. Funakoshi
Faculty of Pharmaceutical Sciences, Kyoto University
Kyoto 606 (Japan)
Prof. Dr. Y Yamamoto, Y. Oguchi, Associate Prof. Dr. T. Uyehdra
Department of Chemistry, Faculty of Science, Tohoku University,
Sendai 980 (Japan)
[**I We thank Dr. G. J. Hanson, Department of Medicinal Chemistry, G . D
Searle & Co., Skokie, Ill, USA., for sending us the 'H-NMR spectra of
authentic rert-butyl N-[(IS, 2S)-l-benzyl-2-hydroxy-3-butenylcarbonate
and its (lS, 2R)-isomer. We also thank Dr. P . Herold. Ciba-Geigy AG.
Zentrale Forschungslaboratorien, Basel, Switzerland, for providing us
with the 'H-NMR spectra ofauthentic tert-butyl(4S. 1'S)-4-(l-hydroxy-2propenyI-2,2-dimethyl-1,3-oxazo~idine-3-carboxylate
and its isomer. This
work was supported by the Sound Technology Promotion Foundation.
Verlagsgesellschajt mbH, 0-6940 Weinheim, 1990
0570-0833/90/0707-0801$ 0 3 S0+.25/0
801
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forma, consisting, compounds, chains, ring, eighth, six, tetrahedral, lio4, membered, mno4, li2, na10
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