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An Unusual Polyoxovanadium Organophosphonate Anion [H8(VO2)16(CH3PO3)8]8.

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Crystals of 3 b are orthorhombic, space group Pbca, a = 18.944(6),
~,0,(OCH3),,(C,0,)]2e[21
and the C6H,COZe group in
b = 19.061(6),~=7.219(3)A;2=8;p,,~,=
1.31(1),pca,c= 1 . 2 9 0 g ~ m - ~ .
the [V606(p-O)4(p-0,CC,H,)]6e[81anion. Here we describe
Data were collected to a maximum 2t?(L,.,0.Ke)= 48". Full matrix leastthe synthesis and structure of 1, a new heteropolyoxovanasquares refinement of positional and anisotropic thermal parameters for
date based on VO, square pyramids and R-PO, tetrahedra
all atoms (fixed H atoms, except for H attached to 0 5 , total parameters = 167); R = 0.072 and R, = 0.075, 1354 data for which I > 1.96 o(l).
with p, and p3 connections.
Further details of the crystal structure investigation are available on request from the Director of the Cambridge Crystallographic Data Centre,
[N(CH,)418[H6(Vo,),,(CH3PO~)*l ' 11 HZO
1
University Chemical Laboratory, Lensfield Road, GB-Cambridge CB21
1EW (UK) on quoting the full journal citation.
X-ray structrual analysi~[~l
of 1 revealed the presence of
a) J. B. Lando, H. Morawetz, J. Polym. Sci. Part C 4 (1964) 789; b) J. B.
Lando, J. Semen, J. Polym. Sci. Polym. Chem. Ed. 10 (1972) 3003; c) Y. V.
discrete Me,N@ ions and water of crystallization in the latKissin in J. I. Kroschwitz (Ed.): Concise Encyclopedia of Polymer Science,
tice, as well as [H6(V0,),6(CH3P0,),]~oanions (Figure 1)
Wiley. New York 1990, pp. 1087-1107.
which each contain a single Me,N@ cation at their center.
H. Morawetz, 1. D. Rubin, J. Poiym. Sci. 57 (1962) 669.
The formulation of the anion is based on the results of the
F. M. Costachuk, D. F. R. Gilson, L. E. St. Pierre, Macromolecules 3
(1970) 393; ibid. 4(1971) 16; b) J. H. O'Donnell, R. D. Sothman, J. Macroredox titration["] which indicates that two of the total of
mol. Sci. Chem. A 1 4 (1980) 879.
sixteen
vanadium atoms are Vv and fourteen are VIV. The
G. Adler, Trans. Am. Crystallogr. Assoc. 7 (1971) 55, and references
therein.
For solid acenaphthylene, a dose of 100 Mrad y-radiation yields 2.1 % of
trans-cyclodimer: A Chapiro, G. Lozach, Inr. J. Radiat. Phys. Chem. 4
(1972) 285.
Polymerization behavior: a) M . L. Miller, J. Skogman, J. Polym. Sci. Part
A 2 (1964) 4551; b)T. Kitano, T. Fujimoto, M. Nagasawa, Macromolecules 7 (1974) 719; c) Y Muroga, M. Nagasawa, Polym. J. 18 (1986)
15.
Dimerization: a) 0. C. Bockman, C. Schuerch, J. Polym. Sci. Part B 1
(1963) 145; b) H. V. Pechmann, Ber. Dtsch. Chem. Ges. 33 (1900) 3323;
c) M. Ikeda, T. Hirano, T.Tsuruta, Tetrahedron 30(1974) 2217; d) T. SaeI
Chem. Soc. Chem. Commun. 1968.
gusa, Y. Ito, S . Kobayashi, S. Tomita, .
273;e) T. Saegusa, Y Ito, S. Tomita, H. Kinoshita, J. Org. Chem. 35 (1970)
03e'
670.
(141 Under conditions of high temperature and pressure, solution trimerization
of methyl acrylate has been observed in 17% yield: J. 0. Metzger, P. KOII,
Makromol. Chem. 184 (1983) 63.
1151 Certain butadiene derivatives are a notable exception: B. Tieke, G. Chapuis, ,4401. Cryst. Liq. Cryst. 137 (1986) 101.
[16] K. Naruchi, Chiba University, personal communication.
[17] J. E. Willard in Farhataziz, M. A. J. Rogers (Eds.): Radiation Chemistry,
Principles and Applications, VCH, Weinheim 1987, pp. 395-434.
An Unusual Polyoxovanadium Organophosphonate
Anion, [H,(V0,),,(CH,P0,),]8e **
By Guohe Huan,* Allan J. Jacobson, and Victor W Day
Although the chemistry of polyoxovanadates is very diverse, a few structural motifs are commonly observed.[']
Vanadium atoms are usually square pyramidally coordinated by oxygen atoms. The VO, square pyramids are then condensed by sharing edges to form dimers as observed in
VOSO, . 3H,0L2]or larger units, for example, the ring of
eight edge-shared square pyramids [V,O,,] found in the anand [V12032]40.[3b1
The
ions [V,0,(OCH3),6(C,o,)]2e[3a1
basketlike shape of the [V,,03,]4e anion is completed by
condensation with four additional VO, square pyramids
through formation of p3-0 connections. In the closo anion
~ , , 0 3 6 ] 5the
0 , shared
[ 4 1 oxygen atoms are either p, or p3
connected, whereas in the [V,,O,,(X)]"o (X = H,O, VO,,
SO,, Br, and
anions they are all of the p3 type. Other
molecular units may also be used to complete the connectivity in polyoxovanadates, for example, the oxalate ion in
[*I Dr. G. Huan, Dr. A. J. Jacobson
Exxon Research & Engineering Company
Annandale, NJ 08801 (USA)
Dr. V. W. Day
Crystalytics Company
Lincoln, NB 68501 (USA)
[**I We thank D.P. Goshorn for magnetic measurements and M . A. Greaney
for help with the cyclic voltammetry.
422
Q VCH Verlagsgesellschaft mbH, W-6940 Weinheim, 1991
Figure 1. Perspective plots ofanion 1 in the crystal structure. Top: View perpendicular to the crystallographic C4-axis at 1/4.1/4, z in the unit cell; hydrogen
bonds are indicated by dashed lines. Atoms labeled ', ",or * are related to atoms
without one ofthose labels by the symmetry operationsy, ~ / ~ - xz,; I / ~ - X , +y,
z; and l/z-y, x, z , respectively. Below: View down the C,-axis; V, green, P blue,
0 red, C gray, H white. Bond distances [A] and angles I"] of interest: V-Ox.,,
1.580(4)-1.607(4), V-(p3-O) 1.925(4)-1.938(4), V-(p2-O(H)) 1.966(4)-1.990(4),
V-(pZ-O) 1.964(4)-1.979(4), Vw,,,,-Vwaj,,= 2.932(1), V,,;,-V,,,,
3.060(lt
3.066(1), O-(pz-O(H))2.76(1)-2.82(1); 0,e,m-V-(p3-O)107.8 (2)-112.6(2), O,ermV-(pZ-O(H)) 105.9(2)-108.0(2), 0,e,m-V-(p2-O)
106.5(2)-109.8(2), (p3-O)-V-(p30) 80.9(2)-81.3(2), (p3-0)-V-(pyO(H)) 76.3(2)-77.1(2), (p3-O)-V-(p2-O)
88.3(2)-91.4(2), (p2-0)-V-(p2-O(H)) 87.3(2)-87.9(2), (p2-O)-V-(p2-O)84.3(2)8 5 3 2 ) ; Vw,,,t-(~3-O)-V,,,,, 98.3(2)-98.5(2), V,,,,,-(p3-O)-V,,,, 104.4(2)-105.2(2),
V,,,,,-(fi,-O)-V,,,
144.7(2)-146.1(2) ("Waist" designates atoms between the
rims of the tire, "ring" the atoms in the outer rings).
0570-0833/91/0404-0422$3.50+ .25/0
Angew. Chem. Inr. Ed. Engl. 30 (1991) No. 4
anion possesses rigorous crystallographic C, symmetry and
resembles a set of chains on a tire (recognized best when
Fig. 1 (top) is turned through 90”). It consists of four condensed (VO,), tetramers, which span the “tread” and are
covalently linked together along each “rim” by four P0,C
tetrahedra through corner-sharing oxygen atoms. The
H,.,V,O, unit arises when distorted VO, square pyramids
share an edge to form dimers which in turn share half of a
long dimer edge to form step-shaped tetramers (see Fig. 2).
P
0
group decreases and that the vanadium oxidation state can
be controlled by varying reaction conditions.
Experimental Procedure
-
To 1.152 g (12 mmol) CH3P03H, (Alfa), 0.300 g (2 mmol) V,03 (Alfa), and
0.364 g (2 mmol) V,O, (Alfa) in a Teflon lined autoclave was added 2 mL of
distilled water followed by 6.4 g Me,NOH (25% in water, Aldrich). The autoclave was filled to 80% with distilled water and heated at 200 “C for 2 days. The
autoclave was then cooled to room temperature. The black, prismatic crystals
of the reaction product 1 (yield 0.60 g, 42% based on vanadium) were suction-filtered, washed several times with distilled water, and air-dried. Satisfac. Main absorption bands in the
tory elemental analysis for C,,H,,,N,V,,P,O,,
IR spectrum (KBr pellet): ;[cm-’] = 3399 (s), 3010 (m), 1625 (m), 1480 (s),
1410 (m), 1300 (s), 1110 (s), 1050 (s), 1000 (vs), 970 (vs), 935 (vs), 770 (m), 720
(s), 700 (s), 615 (s), 570 (s), 530 (s), 485 (s), 435 (m).
-
Received: August 20,1990
Revised: January 2, 1991 [Z 4141 IE]
German version: Angew. Chem. /03 (1991) 426
CAS Registry numbers:
1, 132698-13-6; 1 (without 11H,O), 132672-13-0; [H,(V0,),6(C,H,P03)8]132644-34-9; V,O,,
(Me,N),, 132672-15-2; [H,(V0,),6(C,H,P0,),](Me4N)9,
1314-34-7; V20,, 1314-62-1; CH3P03H,, 993-13-5; C,H,P03H,, 6779-09-5;
C,H,P03H,, 1571-33-1.
Figure 2. A projection of the tetramer and its covalently bonded CH,POze
groups viewed as in Figure 1 top.
Each organophosphonate group shares two of its oxygens
with one tetramer and its third oxygen with the adjacent
tetramer. This results in the formation of sixteen-membered
(-0-V-0-P), rings (whose atoms are coplanar within 0.20 A)
along each “rim of the tire”.
The six hydrogen atoms are disordered over eight sites in
the anion and are covalently bonded to a V-0,-V oxygen
atom. They form hydrogen bonds along the “tread” from
the covalently bonded 0, oxygens in one tetramer to “nonor 04=)
atoms in an adjacent terim” P-0,-V oxygen (03a
tramer. A total of six such hydrogen bonds are used to stabilize each [H6(V0,),6(CH,P0,),]8~ anion. The average
oxygen-to-oxygen distance across the 16-membered rings at
each “rim” is 6.68 8, and between the rings is 5.86 8,. If the
oxygen ionic radius is assumed to be 1.40 A, the free diameter of each 16-membered ring is estimated to be 4 A. The
eight-membered silicon (aluminum) oxygen atom ring in zeolite A has similar dimensions. The free diameter across the
“tire” midway between the two “rims” is much bigger
(10.13 A average oxygen-to-oxygen distance, free diameter
-7.5 A). The Me,N@ ion at the center of each “tire” is
disordered about the crystallographic C, axis which contains
the nitrogen and one methyl carbon atom.
1 is soluble in water and in a mixture of CH,OH/CH,CN.
In the presence of oxygen, aqueous solutions gradually
change color from dark to yellow indicating oxidation of V’”
to V”. Cyclic voltammetry measurements under anerobic
conditions in degassed water did not show reversible redox
behavior. When exposed to air, the crystals of 1 slowly degrade by losing the water of crystallization.
The ethyl and phenyl analogues have also been prepared
in similar hydrothermal syntheses from the corresponding
phosphonic acids. The ethyl compound precipitates as deep
blue prismatic crystals isostructural with 1 and contains the
The phenyl analogue
anion [H,(V0,),6(C,H,P0,),]8G.
forms black hexagonal prismatic crystals with space group
C2/c but contains a structurally similar anion
[H,(VO,), 6(C,H,P0,),]9e. Preliminary results indicate that
the solubility in water increases as the size of the organic
-
Angew. Chem. In[. Ed. Engl. 30 (1991) No. 4
[I] M. T. Pope, A. Miiller, Angew. Chem. 103 (1991) 56; Angew. Chem. Int. Ed.
Engl. 30 (1991) 49.
121 M. Tachez, F. Theobald, Acta Crysrallogr. Sect. B 36 (1980) 2873.
[3] a) Q. Chen, S . Liu, J. Zubieta, Inorg. Chem. 28 (1989) 4433; b) V. W
. Day,
W. G. Klemperer, 0. M. Yaghi, 1 Am. Chem. Soc. 111 (1989) 5959.
[4] A. Miiller, E. Krickemeyer, H. Penk. H.-J. Walberg. M. Bogge, Angew.
Chem. 99 (1987) 1060; Angew. Chem. I n f . Ed. Engl. 26 (1987) 1045.
[5] G. K. Johnson, E. 0. Schlemper, 1 Am. Chem. Soc. 100 (1978) 3645.
(61 A. Miiller, J. Doring, H. Bogge, E. Krickemeyer, Chimia 42 (1988) 300.
[7] A. Miiller, M. Penk, R. Rohfling. E. Krickemeyer, J. Doring, Angew.
Chem. 102 (1990) 927; Angew. Chem. Inr. Ed. Engl. 29 (1990) 926.
[8] D. Rehder, W. Priebsch, M. von Oeynhausen, Angew. Chem. 101 (1989)
1295; Angew. Chem. In[. Ed. Engl. 28 (1989) 1221.
[9] 1: Tetragonal, space group W/ncc (No. 130) with a = 23.660(3), c =
22.708(3)A, V = 12.711(3)A3, and Z = 4 (pcalEd=1.399gc1K-l;
(Mo,,) = 1.25 mm-I), R = 0.041 for 3130 independent reflections having
28 < 48.3” and I > 3a(l); Nicolet P1 auto-diffractometer. graphitemonochromated Mo,, radiation. The structure was solved at Crystalytics
Company using “Direct Method” techniques with the Siemens Nicolet
SHELXTL-Plus software package. Further details of the crystal structure
investigation may be obtained from the Fachinformationszentrum Karlsruhe, Gesellschaft fur wissenschaftlich-technischeInformation mbH. W7514 Eggenstein-Leopoldshafen 2 (FRG), on quoting the depository number CSD-54969, the names of the authors, and the journal citation.
[lo] The vanadium oxidation states in I were determined by redox titration.
Samples were dissolved in 1 M sulfuric acid. A known excess of cerium(rv)
ammonium nitrate was added to the vanadium solutions to oxidize all the
vanadium ions to the pentavalent state. The total vanadium content and
the average vanadium oxidation state were determined by potentiometric
titration using a standard solution of ferrous ammonium sulfate. Redox
titrations of 1 gave an average vanadium oxidation state of 4.10 f 0.02.
Parabolic Growth of a Self-Replicating
Hexadeoxynucleotide Bearing
a 3’-5’-Phosphoamidate Linkage **
By Gunter von Kiedrowski,* Britta Wlotzka, Jorg Helbing,
Matthias Matzen, and Stephan Jordan
The search for minimal models of self-replicating systems
based on oligonucleotide constituents or related molecules is
of considerable interest within the context of early biochemical evolution (“RNA-world”).[ll In 1986 we showed that the
[*] Dr. G. von Kiedrowski, Dipl.-Chem. B. Wlotzka, Dr. J. Helbing, Dipl.-
Chem. M. Matzen, DipLChem. S . Jordan
Institute for Organic Chemistry of the University
Tammannstrasse 2, W-3400 Goettingen (FRG)
[**I This work was supported by the Deutsche Forschungsgemeinschaft and
the Fonds der Chemischen Industrie. The results were presented at the
symposium on “Molecular Biology and the Origin of Life” held in Berkeley, USA, July 15-21, 1990.
Q VCH Verlagsgesellschafi mbH, W-6940 Weinheim, 1991
+
0S70-0833/91/0404-0423S 3.50 .2Sj0
423
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