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Anion Structure of Tetrabutylammonium Octamolybdate [N(C4H9)4]4Mo8O26.

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Fig. I . Anion structure of tetrabutylammonium hydrogen tetravanadate
[ N ( C ~ H ~ ) ~ ] ~ H2 . V ~ O I
The distances between the bridging 0 atoms and vanadium
have an average value of 1.80A and those between vanadium
and the terminal 0 atoms, except 0(9), 1.62A. The oxygen
atom O(9) is conspicuous for its high temper?ture factor and
its significantly longer V-0 distance (1.86A); it apparently
exists (preferentially)in protonated form. The nitrogen atoms
of the cations assume an approximately octahedral arrangement around the polyanion. ’H-NMR measurements in deuteriochloroform show the OH proton to undergo extremely
ready exchange (signal at - 3.99 ppm).
The Raman spectrum of the tetrabutylammonium salt
resembles the spectrum of an alkali metal vanadate solution
that has acidified up to the “metavanadate” level ( Z = I), thus
indicating that such solutions also contain the cyclic tetravanadate ion. The polarized bands correspond to totally symmetric
vibrations of terminal (947cm- ’) and bridging (477 cm- ’)
oxygen atoms and of the vanadium atoms (325cm-I). The
bands at 920 and 628 cm- are assigned to asymmetric vibrations of terminal and bridging oxygen atoms. The symmetrical
VOV stretching vibration is expectedly split in the solid state
spectrum (512 and 471 cm-’); the angles V(l)-O(l)-V(2)
and V(1)-0(4)-V(4)
are 132”, the angles V(2)-0(2)-V(3)
and V(3)-0(3)-V(4)
146”.The Raman spectrum of a sodium
“metavanadate” solution remains unchanged even at high
dilutions (up to 4 x
M in V); there is no evidence for
a concentration-dependent equilibrium between tetravanadate
and trivanadate ions”].
date [N(C4H9)4]2M06019in acetone leads to crystallization
of the octamolybdate [N(C4H9)4]4M08C2 6 . The same compound is obtainable in finely crystallint form on treatment
of a slightly acidified aqueous solution of sodium molybdate
with tetrabutylammonium bromide.
We have solved the structure by X-ray methods on the
basis of 3295 nonequivalent reflections measured with a Syntex
four-circle diffractometer and refined it to an R value of 5.5 %.
In the monoclinic arrangement P21/n the compound has the
lattice paramete:s
a = 15.086z O.OO3, b = 15.997 & 0.003,
c=18.528+0.003A; /?=91.31 +C.Ol”; Z=2.
The centrosymmetric anion consists of a ring made up
of six M o o 6 octahedra (as in T~Mo,O$;[’~)linked to one
M o o 4 tetrahedron above, ant another below, its octahedral
cavity (Fig. 1a). However, in view of the widely varying molybdenum-oxygen distances it can also be viewed as a loose
addition compound between two MOO:- units and a (neutral)
Mo6OI8 ring made up of distorted M o o 4 tetrahedra. The
distances between the Mo atoms and the termi!al
oxygen
atoms O(7) to O(13) range from 1.667 to 1.692A, and the
distances to the bridging atoms O(4) to O(6) from 1.881 to
1.917A. The distances of the tricoordinated atoms 0(1) to
O(3) (Fig. 2) of the MOO:- inits to the Mo atoms of the
ring are unusual (2.35 to 2.53A) and correspond to bond
orders of 0.35 to 0.2r21.Mo( 1) is in an almost ideal tetrahedral
coordination with the 0-Mo(1)-0
angles between 108.1
and 110.6”.The distances between adjacent Mo atoms within
the ring are 3.378 to 3.409A the distances between these
atoms and Mo(1) 3.770 to 3.8 6A, and the distance Mc$l)Mo(1’) 3.697A. The standard deviations are <O.OOl A for
the Mo-Mo distances and <0.01 A for the Mo-0 distances.
’
Received: January 12, 1976 [Z 444a IE]
German version: Angew. Chem. 88, 385 (1976)
Publication delayed at authors’ request
&
-
Fig. 1. Polyhedral structural model of MosO:;
salt (a) and in the ammonium salt (b)
in the tetrabutylammonium
CAS Registry number:
[N(C4H9)4]3HV4012, 59005-33-3
[l] a) Gmelins Handbuch der Anorganischen Chemie, Syst.-No. 48, Vol.
1, pp. 149ff.’(1967).b) Z is the ratio of reacted H + ions to the number
of HVOa- originally present. At Z = 1 , H2VO; is formally present
which is formally converted into VO; by elimination of H Z O(formation
of “meta-acid”).
[2] H . 7: Eaans, Jr., Z. Kristallogr. 114, 257 (1960).
[3] P . Sedlaczek and K . Dornberger-Schifi Acta Crystallogr. 18, 407 (1965).
[4] J . Fuchs, S. Mahjour, and R . Palm, Z. Naturforsch, in press.
[S] D. A . Koster and A . J . Wagner, J. Chem. SOC.1970, 435; H . M . Ondik,
Acta Crystallogr. 17, 1139 (1964).
[6] M! Hilmer, Acta Crystallogr. 17, 1063 (1964).
[7] F . Briro, N . lngri, and L. G . Sill&: Acta Chem. Scand. 18, 1557 (1964);
P. H . Rieger, Aust. J. Chem. 26, 1173 (1973).
Anion Structure of Tetrabutylammonium
Octamolybdate [N(C4H9)4]4M~S026
By Joachim Fuchs and Hans H a r d ’ ]
Addition of an alcoholic solution of tetrabutylammonium
hydroxide to a solution of tetrabutylammonium hexamolyb[*I Prof. Dr. J . Fuchs and Prof. Dr. H. Hart1
Institut fur Anorganische Chemie FB21-WE1 der Freien Universitat
Fabeckstrasse 34-36, lo00 Berlin 33 (Germany)
Angew. Chem. lnt. Ed. Engl. J Vol. 15 ( 1 9 7 6 ) No. 6
W
Fig. 2. Anion structure of tetrabuty ammonium octamolybdate; distances
in A.
This anion is an isomer of the anion occurring in ammonium
octamolybdate (NH4)4M08026.4H20[31which is made up
solely of MOO, octahedra (cf. Fig. 1). Thus the present struc-
375
tural elucidation provides the first proof of structural isomerism in discrete isopolyanions. In solution (e.g . in acetonitrile)
tetrabutylammonium octamolybdate readily transforms into
the hexamolybdate [N(C4H9)4]2M06019.The bonding situation suggests that the mere approach of a negative charge
to the oxygen atom O(13) can lead to the release of a MOO:unit. The structure provides an indication of the addition
and elimination mechanisms involved in the formation and
mutual interconversion of polyions.
Received: February 27, 1976 [Z 444b IE]
German version: Angew. Chem. 88, 385 (1976)
CAS Registry number:
[N(C4H9)4]4M08026, 59054-50-1
[l] H. T Evans Jr., J. Am. Chem. SOC.90, 3275 (1968).
[2] R. Allmann, Acta Crystallogr. B27, 1393 (1971).
[3] I. Lindqrist, Acta Crystallogr. 5 , 667 (1952); L. 0. Atomjan and 0.N .
Krasotschka, Zh. Strukt. Khim. 12, 342 (1971).
C12H1002and Thermolabile C1lHloO Ketones from
Bullvalene uia Carbonyliron Complexes[']
By Rudolf Aumannp]
In the past few years synthetic methods have been reported
in which highly reactive organic molecules (carbenes, cyclobutadiene, trimethylenemethane, norbornadienonec21)have been
initially stabilized by coordination to metal atom centers and
subsequently liberated from the complex by a change in the
oxidation state of the metal or displacement reactions and
induced to undergo reaction.
Such a process permitted preparation of the tetracyclic
diketone (8) and the thermolabile tricyclic monoketone ( 4 )
from bullvalene via the readily accessible carbonyliron complexes ( 1 ) and (7)c31. Compound ( 4 ) and the products of
its thermal isomerization ( 5 ) and (6) are new representatives
of the C1'HloO ketonesC4l, which possess theoretical interest.
m.p. 80°C; m/e=158; 'H-NMR (CDC13): 7=3.39 (dd, H-5,
H-11; J = 6 , SSHz), 4.06 (AAXX' system, H-2, H-3), 4.39
(dd, H-6, H-10; J = 8 , ~ S H Z )7.0
, ("t", H-7, H-9; J = 8 , ~ H z ) ,
7.3 (m, X part of an AA'XX' system, H-I, H-4); ',C-NMR
(CDC13): 6 ~ m
(>C=O)= 206.3 ppm; IR (KBr): v(>C=O)
1700cm - '3.
In contrast to the carbonyliron complex (2) of the ketone
( 4 ) , which slowly rearranges at 100°C to (3) [95% in 3 d ;
colorless crystals, m.p. 115-1 17"C ; m/e = 298 ; IR (hexane):
v(C=O) 2054, 1986cm-'; IR (KBr) v(>C=O) 1720cm-'],
free ( 4 ) already isomerizes slowly in solution at 25"C, and
quantitatively within 1 h at 55°C by Cope rearrangement
to give tricyclo[5.4.0.02~"]undeca-3,5,9-trien-8-one ( 5 )
[colorless crystals from hexane, m. p. 47°C; m/e= 158; 'HNMR (CDC13): 7 ~ 3 . 0 2(dd, H-10; J = 6 , lOHz), 3.56 (dd,
H-6, J = 8 , 11 Hz), 3.9-4.1 (m, H-4, H-5), 4.02 (d, H-9;
J=lOHz), 4.35 (dd, H-3; J=11, CU. 3HZ), 6.80 (dd, H-7;
J=7.5, ~ H z )7.66
, ("q", H-1; J=7.5, 7.5, 7.5Hz), 7.93 (ddd,
H-2; J=7.5, 8, ca. 3Hz), 8.46 (ddd, H-11; J = 6 , 7.5, 8Hz);
13C-NMR (CDC13): &,s(>C=O)= 196.5 ppm; IR (KBr):
v(>C=O) 1660 cm-'I.
At 110°Ccompound ( 5 ) isomerizes cleanly via a vinylcyclopropane/cyclopentene rearrangement (ca.95 % in 1 h) to tricycIo[5.4.0.02~9]undeca-3,5,10-trien-8-one(6) [colorless crystals
from pentane, m.p. 40°C; m/e=158; 'H-NMR (CDC13):
r=3.12 (dd, H-11; 5 ~ 5 . 5 3.0Hz),
,
3.72 (dd, H-10) J 4 . 5 ,
3.5Hz), 3.7 to 4.3 (m, H-3, H-4, H-5, H-6), 6.55 ("s", H-7),
6.9-7.2 (m, H-2, H-9), 7.43 ("s", H-I); 13C-NMR (CDCI3):
B~~s(>C=O)=210.0ppm;IR (KBr): v(>C=O) 1735cm-'].
The tetracyclic diketone (8) [colorless crystalline needles,
m.p. 208°C; m/e=186; 'H-NMR (CDCI3): r=3.84 (dd, 2 H ;
J=8.0, 8.0Hz), 4.15 (dd, 2 H ; J=6.0, 8.0Hz), 6.55 (m, M
part of an AA'MM' system, 2H), 7.36 ("dd", 2H; 5=7.5,
8.0 Hz), 7.52 (A part of an AA'MM' system, 2 H); ' 3C-NMR
(CDC13): &MS(>C=O)=208.7ppm; IR (KBr): v(>C=O)
1735cm- '3 is obtainable in quantitative yield by carbonylation of (7)c31 (100atm of CO, S O T , 2d).
Received: November 17, 1975 [Z 358 IE]
German version: Angew. Chem. 88, 375 (1976)
Publication delayed at author's request
CAS Registry numbers:
(I), 35443-07-3; (2), 58312-76-8; (3), 58312-77-9; ( 4 ) , 58298-58-1; (5).
58298-59-2; (6), 58298-60-5; (7), 35443-09-5; (X), 58298-61-6; bullvalene,
1005-5 1 -2
[I]
123
[3]
[4]
[5]
(7)
(8)
Carbonylation of ( 1 ) (100atm of CO, 7 5 T , 24h) leads
to d i s p l a ~ e m e n t ~
of~ ]the n-allyl/o-bonded Fe(C0)3 group
affording the mononuclear carbonyliron complex (2) [SO % ;
yellow crystals, m. p. 100-102°C; m/e=298; IR (hexane):
v ( C S 0 ) 2039, 1977, 1966cm-'; IR (KBr): v(>C=O)
1710cm- '1. Oxidative decomposition of (2) with FeC13 in
ether (0"C, 10min) gives tricyclo[5.4.0.04~9]undeca-2,5,10trien-8-one ( 4 ) [SO % ;colorless crystals from benzene/hexane,
Na,NO,-Not
376
an Orthonitrite
By Martin Jansen ['I
exists
So far it has remained unclear whether Na,NO,['.
as a salt of"orthonitrous acid" or as an adduct Na,O . NaNO,;
cryoscopic investigations in molten LiNO, and in an LiNO,/
KNO, eutectic indicate existence of the anion NO:-"].
[*I
[*] Priv.-Doz. Dr. R. Aumann
Organisch-chemisches Institut der Universitat
Orltans-Ring 23, 4400 Miinster (Germany)
Part 3 of the series: Organic Syntheses with Transition Metal Complexes.
This work was supported by the Deutsche Forschungsgemeinschaft and
the Fonds der Chemischen 1ndustrie.-Part 2: ref. [ S b].
Cf., e.g., E. 0.Fischer, Angew. Chem. 86, 651 (1974); G. F. Emerson,
L. Watts,and R. Pettit, J. Am. Chem. SOC.87,131 (1965); J. M. Landesberg
and J . Sieczkowski, ibid. 91, 2120 (1969); G. F. Emerson, K . Ehrlich,
W P . Giering, and P. C . Lauterbur, ibid. 88, 31 72 (1966).
R. Aumann, Chem. Ber. 108, 1974 (1975).
M. J . Goldstein and S.-H. Dai, Tetrahedron Lett. 1974, 535; J . T Grows
and K . W Ma, J. Am. Chem. SOC.97,4435 (1975).
a) R . Victor, R. Ben-Shoshan, and S. Sarel, Tetrahedron Lett. 1970,
4253; b) R. Aumann and J. Knecht, Chem. Ber. 109, 174 (1976).
Dr. M. Jansen
Institut f i r Anorganische und Analytische Chemie der Universitat
Heinrich-Bum-Ring 58,
6300 Giessen (Germany)
Angen,. Chem. Int. Ed. Engl.
Vol. 1 5 (1976) NO. 6
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structure, 4mo8o26, anion, octamolybdate, tetrabutylammonium, c4h9
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