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Dipicolinato(hydroxylamido-O N)(nitrosyl)aquavanadateЧA Nitrosyl Complex of Vanadium with Уside onФ Coordinated Hydroxylamine.

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C 0 M M U N I C AT10 N S
coordinated dipicolinato ligand (dipi~)'~]
and a strong band
at 1530cm-' which we assign to a v(N=O) vibration.
The structure of the anion (3) was determined by X-ray
spectroscopy (Fig. 1). Cs[V(dipic)(H2NO)(NO)(H20)]
'2 H2O
crystallizes in the orthorhombic space group DM-Pcmb with
a=839.4(3), b=884.3(2), c= 1936.1(6)pm, 2=8. Refinement
with structure factors of 1260 observed independent reflections
[I > 2.58 o(I)] converged to an unweighted R value of 5.9 %.
The positions of the H atoms could not be determined because
of the poor quality of the crystals (platelets).
Dipicolinato(hydroxylamido-O,N)(nitrosyl)aquavanadate-A Nitrosyl Complex of Vanadium with "side
on" Coordinated Hydroxylamine[**I
By Karl Wieghardt, Udo Quilitzsch, Bernhard Nuber, and
Johannes Weissp]
Vanadium(v) undergoes reduction with hydroxylamine in
alkaline or acidic aqueous solution; depending upon the reaction conditions N2, N 2 0 , and NO (as well as NH3) may
be formed[']. A vanadium(v)-hydroxylamine 1 : 1 complex has
been shown to exist in acidic solution[21but so far has not
been isolated.
Reaction of five-coordinated cis-dioxo(dipico1inato)vanawith hydroxylammonium chloride in weakly
date(v) ion
acidic solution (25 "C) affords a colorless neutral complex
( 2 ) , which on the basis of its analytical and IR spectroscopic
data can be formulated as p-0x0-bis[oxo(dipicolinato)(hydroxylamine-N)vanadium(v)].
Fig. 1. Structure of the complex anion (3) in Cs[V(dipic)(H,NO)(NO)( H 2 0 ) ] . 2 H 2 0 (without H atoms). Important bond lengths [pm] and angles
In alkaline solution (I) reacts quantitatively with hydroxylamine (1:2) without evolution of gas (!) to give deep-red
solutions. Addition of solid KCI or CsCl yields air stable
crystalline potassium and cesium salts, respectively. The IR
spectra of these salts show the characteristic bands of the
Prof. Dr. K. Wieghardt [+I, Dip].-Chem. U. Quilitzsch
Institut fur Anorganische Chemie der Technischen Universitat
Callinstrasse 9, D-3000 Hannover 1 (Germany)
Dr. B. Nuber, Prof. Dr. J. Weiss
Anorganisch-chemisches Institut der Universitat
Im Neuenheimer Feld 270, D-6900 Heidelberg 1 (Germany)
['I Author to whom correspondence should be addressed.
[**] This work was supported by the Deutsche Forschungsgemeinschaft
and the Fonds der Chemischen Industrie. We thank Prof. H. Hartkamp,
Gesamthochschule Wuppertal, for valuable discussions.
Angew. Chem. Int. Ed. Enyl. 17 (1978) No. 5
The central vanadium atom is surrounded by a distorted
pentagonal-bipyramidal array of tridentate dipicolinate
ligands, a bidentate hydroxylamido ligand and-in the axial
positions-a nitrosyl and an aqua ligand (the formal coordination number is 7) (Fig. 1). The hydroxylamido ligand is most
probably coordinated as H2N-O-[51. The nitrosyl group
is almost linearly coordinated, and the V-N2 bond length
is relatively short. Analogous bonding has been reported for
the [V(CN),NO]"- ion["]. The H2NO- ligand is coordinated
"side on" via the 0- and the N-atom, the N3-05 distance
corresponds to that of the usual N-0 single bond length.
The smooth reaction course in alkaline medium and the
lack of formation of gaseous reaction products are considered
to be indicative of an intramolecular transfer of two electrons
from N-coordinated hydroxylamine to Vv (formally, V"' and
NOe are formed). This is supported by the following experiment: Reaction of the V"'-complex ( 4 ) with hydroxylamine
in alkaline solution likewise affords (3):
3 H ~ N O H+ 2 OH-
(3) + NH3 + 5 HzO
ature to give products which were characterized as alkylidenediaziridines (I )I1].
However, in this case NH3 is also formed, for the NO'
ligand must now be formed by disproportionation of the
hydroxylamine to ammonia and hyponitrous acid.
(Z).H20: [H3NOH]CI (2.8g) is added in small amounts
to a solution of C ~ [ V ( O ) ~ ( d i p i c ) ] . H(8
~ og)~in
~ I100ml water
(25"C). A colorless, crystalline precipitate is formed, which
is separated by filtration and washed with alcohol and ether
(5.1 g).-The IR and Raman spectra show an intense v(V=O)
band at 980cm-'.
K(3).3H20: A solution of [H3NOH]C1 (1.2g) and KOH
(2.4g) in water (10ml) is added to a solution of K[V(0)2(dipic)]f31in water (30ml). The mixture becomes dark-red in
color on warming (40°C). After 15 h at 2°C orange-colored
crystals are filtered off and washed with alcohol and ether
(3g).-The cesium salt can be precipitated as red crystals
by treatment of an aqueous solution of the potassium salt
with solid CsCI.
(4)Cl.2HZO: An aqueous suspension (30ml) of pyridine2,6-dicarboxylic acid (3.5 g) and vanadium trichloride (3.1 g)
is treated with 15ml conc. HCI and heated to 50°C. Complete
dissolution of the violet suspension takes place, giving a dark
green solution. On cooling to 5 "C yellow crystals of the desired
product precipitate which are filtered off and washed with
alcohol and ether (5g).
All the complexes gave correct elemental analyses [V, C,
H, N (K, Cs, Cl)].
However, X-ray diffraction analysis of the product with
X=CH3 has shown that our compounds are in fact 4-arylimino-2,5,5-trimethy1-4,5-dihydro-l
( 2 ) (Fig. 1).
Received: February 9, 1978 [Z 936 IE]
German version: Angew. Chem. 90,381 (1978)
CAS Registry numbers:
Cs(l), 66225-05-6; K(1), 66225-00-1; (2), 66225-04-5; Cs(3).2H,O, 6622502-3; K(3), 66225-034; ( 4 ) C1,66225-01-2; [H3NOH]C1, 5470-71-1
C h m . 140. 301 (1924).
[t] A . Kurtenacker, F . Wengefeld, z. Anorg.
[ 2 ] C. Bengtson, Acta Chem. Scand. 27,2554 (1973).
[3] K . Wieghardt, Inorg. Chem. 17, 57 (1978); B. Nuber, J . Weiss, K .
Wieghardt, Z. Naturforsch. 336, 265 (1978).
[4] A. Muller, P . Werle, E. Diemann, P . J . Aymonino, Chem. Ber. 105, 2410
(1972); M . G . B. Drew, C. F. Pygall, Acta Crystallogr. 833, 2838 (1977).
I51 This has been demonstrated for a hYdrox~lamido(O,N ) complex of
uranium(v1) by a single-crystal neutron diffraction analysis: H . W W
Adrian, A. iim Tets, Acta Crystallogr. 833, 2997 (1977); ibid. B 3 4 , 88
Reactions of Methanesulfonyl Azide with Ketenimines
(a Revision)[**I
By Gerrit L'abbk, Chih-Chou Yu, Jean Paul Declercq, Gabriel
Germain, and Maurice Van Meerssche [*I
In a previous article, two of us reported that N-aryldimethylketenimines react with methanesulfonylazide at room temper-
p] Prof. Dr. G. L'abb.5,
Dr. C.-C. Yu
Department of Chemistry, University of Leuven
Celestijnenlaan 200F, B-3030 Heverlee (Belgium)
Dr. J.-P. Declercq, Dr. G. Germain, Prof. Dr. M. Van Meerssche
Laboratoire de Chimie Physique et de Cristallographie de I'Universite
de Louvain
Batiment Lavoisier, Place L. Pasteur, 1
9-1348 Louvain-la-Neuve (Belgium)
[**I J.-P. Declercq is indebted to the F.N.R.S. (Belgium) for a fellowship.
Financial support from the Ministry of National Education and from the
F.R.F.C. is gratefully acknowledged.
Fig. 1. Molecular structure of ( 2 6 ) with the important bond lengths [A]
and angles [degrees]. The oxathiazoline ring is planar. Compound (26)
crystallizes monoclinically in space group
with a = 32.057. b = 5.764.
. P2,/a
cL7.039A; 8=96.49"; Z = 4 . The structure was solved by the MULTAN
77 program [2a] and refined with the X RAY 72 system [2bl to R=0.043
for 1361 reflections (SYNTEX P2, diffractometer; MoKa radiation,
The spectroscopic properties of this unusual ring systeml3'
are compatible with structure (2) [IR (KBr): ca. 1640 (VC=N),
1290, 1160 and 1050cm-'; 'H-NMR (CDCI3): S=1.7 and
1.8 (2CH3 at C-5); '3C-NMR (CDC13) of ( 2 a ) : S=98 and
162 (C-5 and C-4 in the hetero ring), 149, 123, 124 (C-I, C-2,
and C-4 in the phenyl ringr41; MS [M-CH3S02]+ and
[CH3S02]+ as intense signals].
C' u'6Ila\(/l)
+ ('1135o?s:j
. / '<-si)2('l11 - v >
i 133 @ ~ c ' l j l l a ~ ( / ~ ~
YC ,,l14.\(/l)
" h
Mechanistically, the reaction probably involves triazoline
and the zwitterion (5). Although this mode of decomposition is known for acyl azides"], it is without precedent
for sulfonyl azidesL5I.The possible intermediacy of a nitrene
reaction 'Ondion the basis Of the
is completeb
tions (room temperature).
Angew. Chem. I n t . Ed. Engl. 17 (1978) No. 5
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onф, complex, dipicolinato, aquavanadateчa, coordinated, hydroxylamine, nitrosyl, vanadium, уside
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