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Incorporation of Olefin and Nitric Oxide into Organocobalt Compounds.

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oxidation maximum and a similar reduction maximum ;
the charge and discharge polarization is very small.
Further, the areas are identical and correspond to the
amount of charge contained in the substance. Hence,
quinone can be used in the present solid form completely
reversibly to the extent of 100%. The cyclic currentvoltage curve is stationary; the capacity and the resistance
of the electrode change, if at all, only after a long time.
The cyclic current-voltage curve measured in zinc chloride
solution shons the same behavior (Fig. 1).The rest potential
is ca. 400mV, corresponding to a pH of 4.8. However,
in ammonium chloride solution (pH -4.5) the rest potential
is ca. 100 mV less than the redox potential calculated on
the basis of the theoretical pH-dependence. Further, the
current maxima of the cyclic potentiodynamic currentvoltage curves are split (Fig. 1); on charge and discharge
two maxima are obtained that are separated by ca. 70 mV;
these maxima are assigned to the two electron transfer
reactions quinone/semiquinone and semiquinone/hydroquinone-since chloranil does not form a quinhydronef6!
it must be assumed that the intermediate product is the
semiquinone which is stabilized by the ammonium
ions and reacts further only at higher (or lower) potential.
The discharge curves, measured galvanostatically in dilute
sulfuric acid, are almost horizontal at medium current
density, at least up to 90% discharge, and the polarization
on discharge amounts to only 20 to 60mV with respect
to the rest potential (Fig. 2). Further it can be seen from the
Discharge 1%1
Quinone cathodes in aqueous electrolytes can be
regenerated by air. Normally hydroquinones are not
oxidized by oxygen, but the capacity of chloranil or
duroquinone in contact with catalytically active charcoal
was regenerated quantitatively after discharge in dilute
sulfuric acid or ammonium chloride solution provided
that air is supplied by use of a hydrophobic electrode[81.
Since the active mass was hydrophilic, oxidation of the
hydroquinone occurs by an electrochemical mechanism.
At the redox potential of the quinone the oxygen is cathodically reduced and the hydroquinone anodically oxidized
simultaneously at the same electrode. Regeneration can
also be achieved by hydrogen peroxide.
Received: March 29. 1971: Extended: April 20,1971 [Z427 IE]
German version: Angew. Chem. 83.502 (1971)
[l] K J . Verter, Z. Elektrochem. 56, 797 (1952); J K . Dohrmann and
K . J . Vetter, ibid. 73, 1068 (1969).
[2] E. Voss, Chem.-1ng.-Techn. 42, 199 (1970).
[3] W Heisrich. Brennstoffelemente. Verlag Chemie, Weinheim 1965.
[4] H . Binder, A. Kdhling, and G . Sandsrede. Angew. Chem. 79, 903
(1967); Angew. Chem. internat. Edit. 6, 884 (1967); Chem-1ng.-Techn.
40, 543 (1968).
[ 5 ] Measured against a reference electrode: in 2~ H,SO, an
autogenous hydrogen electrode was used, and in the salt solutions a
calomel electrode. The potential values given were recalculated I‘.%
the normal hydrogen electrode
[6] W M . Clark: Oxidation-reduction potentials of organic 5 ) \iLiii>
Williams & Wilkens, Baltimore 1960; J B. Conanr and L. F . Firwr.
J. Amer. Chem. SOC.45, 2194 (1923).
[7] A discharge rate of 1 C denotes that discharge is at a current
strength such that the total charge capacity (in Ah) of the electrode is
consumed in 1 h. The quantity thus has the dimensions [total amount
ofchargejh]; a discharge rate of2 C corresponds to discharge at double
the current strength, i. e. to a discharge time of 0.5 h.
[8] H. Alt, H. Binder, A. Kdhling, and G . Sandstede. Paper read at
Conference of Comite international de Thermodynamique et de
Cinetique Electrochimiques. Prague. Sept. 1970: extended abstract.
p. 319; Electrochimica Acta, in press.
Incorporation of Olefin and Nitric Oxide into
Organocobalt Compounds[**][
Fig. 2. Discharge curves of a chloranil cathode. 184 mg of chloranil
mixed with graphite. Electrode surface, 1 cm’; 3N H,SO,; 25°C.
Curve 1 : 600 mA/cm’= 10 C [7]. Curve 2: 300 mA/cm’ = 5 C. Curve 3:
120 mA/cmZ= 2 C. Curve 4: 60 mA/cm2 = 1 C. Curve 5 : 30 mA;cm’
=0.5 C. Curve 6: 3 mA/cmZ=0.05 C.
Figure that the quinone cathode can be particularly
heavily loaded. It is true that the practical capacity
decreases with increasing current density, but it still
amounts to 85% of the theoretical value at a discharge
rate of 2 Cr7].Even a load of 600 mA/cm2 does not lead to
voltage breakdown. The chloranil cathode, further, can
be heavily loaded even at low temperature; at 0°C polarization is only ca. 50 mV larger than at room temperature.
Also, the discharge characteristics in the salt solutions
mentioned are almost horizontal. Therefore, it would also
be possible to use quinone cathodes in primary cells having
greater load capacity for neutral electrolytes, for which
purpose zinc might, for example, be introduced as anode
material. Again, development of secondary cells would be
of interest, because higher energy densities (Wh/kg) can
be obtained than with lead accumulators. Our experiments
with a chloranil electrode in aprotic solvents have shown
that this electrode behaves reversibly also in organic
electrolytes, e.g., lithium perchlorate in acetonitrile or
propylene carbonate, and this makes it possible to develop
a high-energy battery with lithium anodes.
Angew. Chcm. mlernaf. Edit.J Vol. 10 (1971) J N o . 7
By Henri Brunner and Stephan Loskot“]
The system consisting of olefin, CO, and organocobalt
compound is of considerable technical importance, particularly for carbonylations‘21. We have studied the
system consisting of olefin, NO, and organocobalt compound and report here a synthesis starting from these
three components.
p] Prof. Dr. H. Brunner
Fachbereich Chemie der Universitat
84 Regensburg, Universitatsstrasse 31 (Germany)
Dip].-Chem. S. Loskot
Anorganisch-Chemisches Laboratorium der Technischen Universitat
8 Munchen 2, Arcisstrasse 21 (Germany)
This work was supported by the Deutsche Forschungsgerneinschaft.
C,H,Co(CO), reacts with NO to give [C,H,Co(NO)],
However, in the presence of norbornene the new
complex (2) is formed. The latter can also be obtained
from ( I ) , norbornene, and NO at room temperature and
atmospheric pressure in 90% yield.
Compound (2) forms dark crystals, stable in air and
soluble with an intense red color in organic solvents
except aliphatic hydrocarbons ;it is monomeric in benzene.
In its mass spectrum the molecular ion appears at m/e = 278;
fragmentation of the molecule (removal of the olefin,
followed by stepwise loss of the N O groups) indicates
coordination of the ligands through the NO groups to the
cobalt atom. The IR spectrum of (2) in KBr does not
contain any band in the region of NO ligands bound
terminally to metalr4];an intense band at 1357 cm-’ can be
ascribed to the NO stretching vibration weakened by
back donation.
The signal for olefinic protons in the ‘H-NMR spectrum of
norbornene lies at 7 =4.02r51.The corresponding protons of
(2) give rise to a doublet at ~ = 7 . 2 8with a coupling
constant of about 1 Hz. The signal for the bridgehead
protons is shifted from ~ = 7 . 1 6to ~ = 7 . 3 6by complex
formation. The signal for the n-bonded C,H, ring appears
at T = 5.04.
In order to elucidate the structure of the new type of
compound, derivatives were used containing substituted
cyclic olefins instead of norbornene. The double DielsAlder adduct from 2-bromofuran and dimethyl acetylenedicarboxylate yields the complex (3) in which both
olefinic double bonds have reacted.
atoms HA to H, were assigned by double resonance.
As was previously noted for (3),HA and H, do not couple
with one another in ( 4 ) . The constant of the long-range
coupling HA - H, amounts to 1.3 Hz.
The long-range coupling between HA and H, in ( 4 ) as
well as the absence of coupling of HAand H, in ( 3 ) and ( 4 )
are considered as characteristic of endo-protons HA in
systems of the type (3) and ( 4 j r 6 ] .The exo-structure is
thus to be ascribed to the complexes (3) and ( 4 ) .
Similar complexes are formed from ethylene and cyclohexene but have not yet been obtained pure.
Received: April 27, 1971 [Z 425 IE]
German version: Angew. Chem 8.1 546 (1971)
[l] Part 11 of Nitroso-Metal Complexes. - Part 10: H . Brunner and
H.-D. Schindler, J. Organometal. Chem. 19,135 (1969).
[2] J . Falbe: Synthesen mit Kohlenmonoxid. Springer-Verlag, Berlin
1967; C.W Bird: Transition Metal Intermediates in Organic Synthesis.
Logos Press, Academic Press, London 1967, p. 117, 149, 205; A . J .
Chalk and J . F. Harrod: Advances in Organometallic Chemistry.
Academic Press, New York, London 1968, Vol. 6, p. 119.
[3] H . Brunner, J. Organometal. Chem. 12, 517 (1968).
[4] W P . G r i f f h : Advances in Organometallic Chemistry. Academic
Press, New York 1968, Vol. 7, p. 211.
[5] All ‘H-NMR spectra were measured for CDCI, solutions at
60 MHz.
[6] J . Meinwald and Y C . Meinwald, J. Amer. Chem. SOC.85, 2541
(1963); J . C . Dacis, Jr., and TK Van Auken, ibid. 87, 3900 (1965).
Phenylarsenic(v) Trichloride Azide and
Phenylarsenic(v) Chloride Nitride”]
By Volker Krieg and Johann Weidlein“]
(3). R = COOCH,
In the ‘H-NMR spectrum of (3) the protons HA and HA.
give rise to an AB system with resonances at ~ = 6 . 4 3and
r=6.80 and a coupling constant of 5.7 Hz. These two
protons thus occur in the “nitroso” structure (3) on
neighboring carbon atoms. The “oxime” structure, which
would be formed by shift of the protons H A and H,. on
to the oxygen atoms is thus excluded. The signal for the
bridgehead proton HE lies at t=4.49. HE does not couple
with HA and HA..
When the Diels-Alder adduct from cyclopentadiene
and dimethyl acetylenedicarboxylate reacts with
[C,H,Co(NO)], and NO, only the unsubstituted double
bond reacts, with formation of ( 4 ) . The ‘H-NMR spectrum
of ( 4 ) contains a doublet for HA at r=6.77 and a multiplet
Phenylarsenic dichloride dissolved in CCl, reacts with
gaseous chlorine aziderzlexothermally according to
Removal of solvent and unreacted starting materials under
reduced pressure leaves highly viscous, orange-red phenylarsenic(v) trichloride azide ( I ) . The compound is only
moderately soluble in benzene and is hydrolyzed by water
with evolution of considerable amounts of heat. On rapid
heating it decomposes, with black coloration, but not
explosively. Compound ( I ) is, however, also unstable at
room temperature and slowly gives off chlorine and
nitrogen ; thermal decomposition proceeds according to
and goes to completion only at about 100°C in a high
vacuum ; phenylarsenic(v) chloride nitride (2) is evolved.
Compound (2) is a slightly brownish glass at room temperature whose softening point lies at about 70°C. The
hygroscopic compound dissolves in organic solvents and
in weak alkalis. Cryoscopic molecular weight determinations in benzene show the substance to exist as the trimer.
(4), R = COOCH,
for HBat r=6.54. H, and H, form an AB system (H, at
T==7.84; H, at T = 8.20) with a coupling constant of 10 Hz.
Each line of the AB system shows additional fine structure.
The chemical shifts and coupling constants of the hydrogen
In the IR spectrum of ( I ) the characteristic absorption
bands of the azido group can be assigned unequivocally.
Dr. V. Krieg and Dr. J. Weidlein
Institut fur Anorganische Chemie der Universitat
7 Stuttgart 1, Schellingstrasse 26 (Germany)
Angew. Chem. internal. Edit.1 Vol. 10 (1971) 1 No. 7
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oxide, compounds, nitric, olefin, organocobalt, incorporation
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