Oxidative dehydrogenation in complexes of transition metals (Cu(II), Co(II), Ni(II)) with N,N′-di(2-hydroxybenzyl)diamines

Article abstract of DOI:10.1023/A:1011389632581

Potentially tetradentate ligands N,N′-di(2-hydroxybenzyl)ethylenediamine (L¹) and N,N′-di(2-hydroxybenzyl)o-phenylenediamine (L²) and complexes of Cu(II), Co(II), and Ni(II) with L¹ and L² were synthesized. The

Full text of DOI:10.1023/A:1011389632581

Russian Journal of Coordination Chemistry, Vol. 27, No. 7, 2001, pp. 486–492. Translated from Koordinatsionnaya Khimiya, Vol. 27, No. 7, 2001, pp. 521–527.
Original Russian Text Copyright © 2001 by Aidyn, Medzhidov, Fatullaeva, Tashchioglu, Yalchin, Saiyn.
Oxidative Dehydrogenation in Complexes of Transition Metals
(Cu(II), Co(II), Ni(II)) with N,N'-Di(2-Hydroxybenzyl)diamines
A. Aidyn, A. A. Medzhidov, P. A. Fatullaeva, S. Tashchioglu, B. Yalchin, and S. Saiyn
Science and Art Department, Marmara University, Istanbul, Turkey
Institute of Inorganic and Physical Chemistry, Academy of Sciences of Azerbaijan, Baku
Received February 11, 2000
Abstract—Potentially tetradentate ligands N,N'-di(2-hydroxybenzyl)ethylenediamine (L1) and N,N'-di(2-
hydroxybenzyl)Ó-phenylenediamine (L2) and complexes of Cu(II), Co(II), and Ni(II) with L1 and L2 were syn-
thesized. The EPR and electronic spectroscopy methods were used to reveal the octahedral structure of the
Cu(II) complex with L1 in the solid state. In water–alcohol solutions, the Cu(II) and Ni(II) complexes with both
ligands have distorted octahedral structures. The Co(II) complexes form dioxygen adduct with L1. In the pres-
ence of oxygen, the ligands in the obtained complex compounds can undergo oxidative dehydrogenation with
selective formation of the respective disalicylaldimines. In the case of L2, the oxidative dehydrogenation is
observed for the complexes of all studied metals in comparatively mild conditions (T = 30°C, methanol and
other solvents), while in the case of L1, it occurs only with the Co(II) complexes in the presence of pyridine.
The reactions of oxidative dehydrogenation of coor- hydroxybenzyl)diamines (ethylele- and Ó-phenylenedi-
dinated ligands are well known in the literature [1–4].
There are some publications on dehydrogenation of
coordinated primary amines which convert them into
nitriles [5–11], of diamines into diimines [12–19], as
well as on dehydrogenation of the macrocyclic [20–29]
and of other ligands [29–34].
amine), we established that their ligands are also dehy-
drogenated to give the corresponding diimines.
This paper describes the synthesis, structure, and
oxidative dehydrogenation of the Co(II), Ni(II), and
Cu(II) complexes with N,N'-di(2-hydroxybenzyl)ethyl-
enediamine (H2DBED) and N,N'-di(2-hydroxyben-
While studying the properties of the previously
unknown transition-metal complexes with N,N'-(2- zyl)Ó-phenylenediamine (H2DBOPD).
NH
NH
NH
NH
CH2
CH2
O
CH2
CH2
O
M
M
O
O
M(DBED) · nH2O
M(DBOPD) · nH2O
EXPERIMENTAL
buret connected to a thermostatically controlled reac-
tor. Samples of solid complexes or a mixture of a solid
acetate of the corresponding metal and a ligand were
place in a reactor connected to a calibrated gas buret
and a separatory funnel with a pressure leveling. The
system was evacuated, while the reactor was filled with
oxygen and then with a solvent.
The elemental analysis of the obtained compounds
(see the table) was performed by the combustion (car-
bon and hydrogen) and Dumas (nitrogen) methods.
IR spectra (KBr pellets) were recorded on a Specord
M80 (Carl Zeiss) or Mattson 1000 FTIR (Perkin–
Elmer) spectrophotometer. The electronic absorption
spectra were recorded on a Specord M40 and on a UV-
240 (Shimadzu) spectrophotometer. The EPR spectra
were registered on a RE 1306 and on a Radiopan
(Poland) radiospectrometer. Derivatographic measure-
ments were performed on a MOM (Hungary) derivato-
graph.
The oxygen absorption measurements were carried
H2DBED. Ethylene-N,N'-disalicylaldimine (26.8 g,
out with the aid of a thermostatically controlled gas 0.1 mol) was suspended in 40 ml of methanol, and
1070-3284/01/2707-0486$25.00 © 2001 åÄIä “Nauka /Interperiodica”

OXIDATIVE DEHYDROGENATION IN COMPLEXES OF TRANSITION METALS
487
Elemental analysis data for N,N'-di(2-hydroxybenzyl)diamines and their complexes
Content (found/calcd.), %
Compound
Empirical formula
mp, °C
C
H
N
H2DBED
C16H20N2O2
70.33/70.56
52.83/52.48
54.50/54.61
50.58/50.66
52.25/52.35
74.82/74.98
60.02/60.07
58.08/58.15
7.35/7.35
6.03/5.87
5.68/5.72
5.22/5.31
6.52/6.58
6.18/6.29
5.01/5.04
5.25/5.37
10.63/10.29
6.65/6.80
7.82/7.96
7.25/7.38
7.59/7.63
8.64/8.74
6.95/7.00
6.73/6.78
123
179.5–181
201
Cu(DBED)(CH3COO) · H2O
Cu(DBED) · H2O
C18H24N2O5Cu
C16H20N2O3Cu
C16H20N2O5Co
C16H22N2O4Ni
C20H20N2O2
Co(DBED) · O2 · H2O
Ni(DBED) · 2H2O
H2DBOPD
209.5–211
222
110.5
192
Cu(DBOPD) · H2O
Ni(DBOPD) · 2H2O
C20H20N2O3Cu
C20H22N2O4Ni
227
sodium borohydride (5.7 g, 0.15 mol) was added to it mixture (7 : 1) was supplied through a separating fun-
with intensive stirring in small portions. Once all the nel, after which a homogeneous light violet solution of
NaBH4 had been added, stirring was continued for
another 0.5 h, and then the colorless solution was
diluted with a threefold amount of water and acidified
with a 10% HCl solution to pH ~ 7.5. The precipitated
compound was separated on a porous filter, washed
with water, dried, recrystallized from a mixture of eth-
anol–water (1 : 1), and dried in vacuum.
the cobalt complex was formed. When the reactor was
filled with oxygen, the solution color changed to brown
and oxygen absorption was observed to be almost com-
plete in 15–20 min. Heating with simultaneous stirring
was continued for another 1 h. The total absorption of
O2 was ~23 ml. The reaction mixture was evaporated to
1/3 of its volume, and the obtained brown precipitate was
separated and dried in vacuum at 100°ë. The IR spectrum
of the compound formed is fully identical to that of
Co(II) ethylene-N,N'-disalicylaldiminate (Fig. 1).
Cu(DBED)(CH3COO) · H2O. N,N'-di(2-hydroxy-
benzyl)ethylenediamine (H2DBED) (0.272 g, 1 mmol)
was dissolved in 20 ml of methanol, and a solution of
Cu(CH3COO)2 · H2O (0.199 g, 1mmol) in 5 ml of water
was added to it. After several hours, a finely crystalline
precipitate of green color formed which was separated,
washed with water on a filter, and dried in vacuum.
H2DBOPD. O-phenylene-N,N'-di(salicylaldimine)
(6.32 g, 2 × 10–2 mol) (mp = 147°C) was mixed with
50 ml of isopropyl alcohol, and sodium borohydride
Cu(DBED) · H2O. H2DBED (0.544 g, 2 mmol) dis-
solved in 30 ml of ethanol was mixed with Cu(OH)2
prepared by precipitation of aqueous CuSO4 · 5H2O
(0.62 g, 2.5 mmol) with 5% NaOH. Some time later,
dark green fine crystals precipitated which were sepa-
rated and dried.
1
2
Co(DBED) · O2 · H2O was obtained similarly to the
copper complex from Co(CH3COO)2 · 4H2O and
H2DBED. A finely crystalline precipitate was formed
from the obtained solution after it was allowed to stand
in air, and the precipitate was separated and dried in
vacuum.
Ni(DBED)
·
2H2O was obtained from
Ni(CH3COO)2 ·2H2O and H2DBED by the procedure
described above for the Cu(II) and Co(II) complexes.
The obtained green solution was heated to boiling and
allowed to stand and crystallize. In 15–20 min, fine lus-
trous crystals of blue color precipitated which were
separated, washed with ethanol, and dried in vacuum.
Oxidative dehydrogenation of the Co(II) com-
plex with N,N'-di(2-hydroxybenzyl)ethylenedi-
amine. H2DBED (0.272 g, 1 mmol) and Co(CH3COO)2 ·
4H2O (0.25 g, 1 mmol) were placed in a constant-tem-
perature reactor (60°ë) connected to a gas buret and
filled with oxygen. Then, 40 ml of a dioxane–pyridine
–
2000
1500
1000 ν, cm–1
Fig. 1. IR spectra of the product of oxidative dehydrogena-
tion of (1) Co(DBED) complex and (2) Co(II) ethylene-
N,N'-di(salicylaldiminate).
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 27 No. 7 2001

488
AIDYN et al.
The IR and electronic absorption spectra of the
D
product of oxidative transformation of Cu(DBOPD) ·
H2O fully coincide with the spectrum of copper(II) Ó-
phenylene-N,N'-di(salicylaldiminate) (Fig. 2).
0.8
0.6
0.4
0.2
A similar procedure was used to carry out the oxida-
tion of Ni(DBOPD) · 2H2O in a temperature-controlled
reactor. The obtained crystal precipitate had mp >
250°C, and its spectrum completely coincided with the
spectrum of nickel (II) Ó-phenylene-N,N'-di(salicyla-
ldiminate).
3
2
Oxidative dehydrogenation of the Co(II) com-
plex with H2DBOPD was run similar to that of the
complex with H2DBED. The dark brown compound
obtained from the reaction mixture had mp > 250°C.
1
4
The IR spectrum of the product was identical with
that of Co(II) Ó-phenylene-N,N'-di(salicylaldiminate).
200 300 400 500 200 300 400 500
λ, nm
RESULTS AND DISCUSSION
Fig. 2. Electronic absorption spectra of the methanol solu-
Complexes with H2DBED
tions of the products of Cu(DBOPD) · H O conversion in
2
(1) dioxane, (2) tetrahydrofuran, (3) chloroform, and of
(4) copper(II) o-phenylene-N,N'-di(salicylaldiminate) (c =
10 mol/l).
The IR spectra of H2DBED contain a narrow intense
band ν(NH) at 3285 cm–1 and a broad intense band in
the range of 2500–2600 cm–1, which should be
assigned to the stretching vibrations of the amino group
participating in the formation of a hydrogen bond with
a phenol group. This is confirmed by the fact that the
PMR spectrum lacks the H2DBED signal at 5–6.5 ppm,
which is typical of a secondary amine proton.
–3
was added to the mixture in small portions until the
solution became colorless. The amount of NaBH4 spent
was 0.8–1.2 g. The reduced solution was diluted with a
fivefold quantity of water and acidified to pH ~ 8.0. The
obtained product (a nearly white precipitate) was sepa-
rated, washed with water, dried, and recrystallized from
benzene. Then, these white crystals were washed on a
porous filter with ether and were dried.
The electronic absorption spectrum of the H2DBED
methanol solution exhibits two bands due to absorption
of a phenol group at 210 and 274 nm.
The H2BDED behavior in complexation with the
Cu(II) ion in water-methanol solutions is very much
similar to that of tripod ligands [35].
Cu(DBOPD) · H2O. H2DBOPD (0.32 g, 1 mmol)
was dissolved in 40 ml of methanol, and
Cu(CH3COO)2 · H2O in 5 ml of water was added to it.
A finely crystalline green precipitate immediately
formed which was then washed with water and dried in
vacuum at 100°ë. The yield was almost quantitative.
In complexation of H2DBED with copper(II) ace-
tate, two characteristic bands appear in the electronic
absorption spectrum: a band at 390 nm due to the
ligand–metal charge transfer and a d–d band at
~600 nm. These bands allow one to establish the com-
position of the complex in solution depending on the
pH of the medium. When the pH of the medium
changes from 4.1 to 8.0, the band of the d–d transition
shifts from 620 to 590 nm (Fig. 3). One can also
observe a somewhat smaller (as compared with the d−d
band) shift of the band due to the charge transfer from
388 to 379 nm. These shifts can be explained by a
change in the coordination surrounding of the metal
ion.
Ni(DBOPD) · 2H2O was obtained by a procedure
similar to that used to synthesize Cu(DBOPD) · H2O.
H2DBOPD (0.32 g, 1 mmol) was dissolved in 30 ml of
methanol and mixed with Ni(CH3COO)2 · 2H2O
(0.249 g, 1 mmol). The solution turned green. The
compound precipitated as fine blue crystals.
Self-oxidative
transformation
of
the
Cu(DBOPD) · H2O and Ni(DBOPD) · 2H2O com-
plexes. Cu(DBOPD) · H2O (0.4 g) in 50 ml of tetrahy-
drofuran (THF) was boiled with a reflux condenser for
3 h. A dark brown solution was filtered off and allowed
to stand for a long time, after which dark lustrous crys-
tals precipitated from it. The yield was 0.30 g. mp >
250°C.
Complexation of Cu(II) with H2DBED starts at
pH > 4.5. At these values of pH, a band appears due to
a charge transfer from the phenol oxygen to the metal
ion. An increase in pH is accompanied by an increase
in the intensity of this band, which attains its maximum
Similar results were obtained in the oxidation of a at pH ~ 8. The processes occurring in the reaction mix-
dioxane solution of Cu(DBOPD) · H2O with pure oxy- ture with increasing pH can be described by the follow-
gen in a temperature-constant reactor at 45°ë.
ing scheme:
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 27 No. 7 2001

OXIDATIVE DEHYDROGENATION IN COMPLEXES OF TRANSITION METALS
489
+
NH2 O–
NH OH
–H+
+H+
Cu(CH3COO)2
NH O
+ Cu(CH3COO)2
+
NH2 O–
NH OH
+
NH2 O
–H+
OOCCH3
OH2
OH2
OH2
Cu
Cu
NH
O
+H+
+
NH2 O–
NH O
–H2O
+H2O
+
NH2 O–
NH
NH
O
Cu
O
Like in the case with tripod complexes [35], the shift 20°C) point to a distorted octahedral coordination of
of the d–d band upon a change in pH is evidently asso- the central ion (evidently, an elongated octahedron).
ciated with the involvement of the nitrogen atoms into Freshly prepared lustrous blue crystals of the nickel
coordination. One can suggest that pH growth is complex become colorless with time, which is due to
accompanied by a gradual replacement of the oxygen the loss of water molecules. According to data of ther-
atoms in the environment of the metal ion by the nitro- mogravimetric analysis, the first water molecule in the
gen atoms, thus increasing the strength of the ligand Ni(BDED)· 2H2O complex is relatively weakly bound
field and shifting the bands to the region of higher ener- and removed at 120°ë, while the second molecule is
gies, which is experimentally observed.
more strongly bound and is removed at 170°ë.
The copper complex with H2DBED separated in the
crystalline state at pH ~ 7.5 has the composition
Cu(DBED) · H2O, and its IR and electronic spectra
fully coincide with the spectra of the complex obtained
from Cu(OH)2. At the same time, the complex pro-
duced upon reacting copper acetate with H2DBED in a
water–methanol mixture (1 : 5) has a mixed-ligand
composition Cu(CH3COO) · HDBED · H2O.
Interaction of the Co(II) Complex with H2DBED
with Oxygen
Solutions of the Co(II) complex, which are prepared
from the metal salt and H2DBED in dioxane or in a
mixture with pyridine, can absorb oxygen; this capabil-
ity depends on the sequence of introduction of oxygen
The EPR spectrum of a polycrystalline sample of
the Cu(DBED) · H2O complex obtained at room tem-
perature exhibits an intense, nearly symmetric, single
band with ∆H = 150 Gs and g 2.107. This fact can sug-
gest an octahedral environment of the Cu2+ ion in the
solid state due to additional coordination by a central
ion of two oxygen atoms (or nitrogen) from neighbor-
ing molecules.
Transmission, %
60
The EPR spectrum of the Cu(DBED) solution in
THF frozen at 84 K is typical of the distorted octahedral
Cu(II) complexes and has the following parameters:
g|| = 2.21, g = 2.04, and A|| = 195 Gs.
1
40
2
4
3
Cu(DBED) · H2O poorly dissolved in common sol-
vents, however, when a small amount of acetic acid was
added, it dissolved in CHCl3 (CHCl3 : CH3COOH ≈ 15 :
1). The EPR isotropic signal of the complex solution in
this mixture of solvents (Aiso = 75 Gs, giso = 2.113) fully
corresponds to the isotropic EPR spectrum of the
Cu(II) complex obtained from copper acetate and
H2DBED in methanol.
3
4
20
1
2
30 28 26 24 22 20 18 16
–
ν × 10–3, cm–1
The nickel ions and H2DBED form the Ni(DBED) ·
2H2O complex. The electronic absorption spectrum of
this complex in water–alcohol (1 : 1) mixture (the
bands at 340, 420 and 610 nm) and the value of the
magnetic moment of this complex (µeff = 2.86 µB at
Fig. 3. Electronic absorption spectra of an aqueous solution
–3
of a mixture of Cu(CH COO) · H O (10 mol/l) and
3
2
2
–3
H DBED (10 mol/l) at pH = (1) 4.8, (2) 5.8, (3) 6.7, and
2
(4) 7.5.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 27 No. 7 2001

490
AIDYN et al.
and solvent into the reactor. When the system is first changed from light violet-pink to dark brown and oxy-
filled with oxygen and then the solvent is introduced gen absorption occurred in time. The total amount of
after absorption of a small volume of oxygen, no fur- absorbed oxygen corresponded to a molar ratio of
ther absorption is observed. The most probable expla- Co(DBED) : O2 = 1 : 1. Subsequent heating of the solu-
nation of this phenomenon is the formation of nonac- tion at 60°ë resulted in a complete conversion of the
tive Co(III) complexes or stable binuclear peroxide initial Co(DBED) to the respective Co(II) ethylene-
complexes.
In typical experiments, 5 × 10–4 mol of metal acetate
N,N'-di(salicylaldiminate).
The reaction of H2DBED and of cobalt acetate with
and of the ligand were placed in a reactor connected to oxygen in the methanol–water mixture at room temper-
a gas buret, the system was evacuated, and a dioxane– ature yields the oxygen adduct CoDBED · O2 · H2O.
Py mixture (10 : 1) was introduced with stirring. Com- Taking this fact into account, one can suggest that the
plexation was complete within several minutes. When oxidative dehydrogenation in the presence of pyridine
oxygen was supplied, the solution color sharply follows the scheme given below:
O
NH 2 NH
Co
N
N
NH
NH
Co
Py
Co
+ O2
Py
O
O
O
O
O
O
The Cu(II) and Ni(II) Complexes with H2DBOPD
stand for several days. However, this transformation
does not take place in the absence of oxygen.
The electronic absorption spectrum of H2DBOPD
contains absorption bands (λ, nm (ε, mol–1 l cm–1)) due
to the substituted phenol at 225 (1.8 × 104), 273 (9 ×
102) and bands from the Ó-phenylenediamine fragment
at 252 (1.2 × 103), 295 (4.7 × 102). In complexation
with Cu(II) ion, all bands of the ligand undergo a slight
bathochromic shift. In addition, bands at 418 nm (due
to the charge transfer) and at 600 nm (due to the d–d
transition) appear.
In the IR spectrum of Cu(DBOPD) · H2O, the band
due to the stretching vibration of the NH group is very
broad and appears as a small peak in the region of
3208 cm–1, whereas in the H2DBOPD spectrum, it is
very intense and is located in the region of 3220 cm–1.
The Cu(DBOPD) · H2O composition is confirmed
by the data obtained from a thermogravimetric analy-
sis. A 4.5% mass loss is observed in the temperature
interval of 80–110°ë and corresponds to the detach-
ment of one water molecule (theoretical 4.5%).
The d–d band at 600 nm can point to a distorted
octahedral structure of this complex. The pattern of the
EPR spectrum of a polycrystalline Cu(DBOPD) · H2O
sample is typical of Cu(II) complexes with tetragonal
symmetry.
One can suggest that the oxidative transformation
occurs via the Ó-phenylenediamine fragment to yield a
Cu(II) complex containing a quinone diimine fragment.
Nevertheless, the analysis data and comparison of the
electronic and IR spectra showed that in this case, a
known complex, i.e., Cu(II) Ó-phenylele-N,N'-di(sali-
cylaldiminate), is formed, the reaction being selective
and having a yield close to the quantitative yield. It is
noteworthy that the oxidation of the ligand itself under
the same conditions gives a range of products and is
likely to occur through the Ó-phenylenediamine frag-
ment.
The selectivity discovered in the formation of Cu(II)
Ó-phenylene-N,N'-di(salicylaldiminate) indicates that
the oxidation reaction occurs in the coordinated
ligands. It is safe to say that the initial stage of the oxi-
dation reaction is the formation of an intermediate oxy-
gen adduct M(DBOPD) · O2. This can be indirectly
confirmed by the fact that in the case of Co(II), which
forms more stable oxygen adduct Co(DBED) · O2, no
Co(DBOPD) complex forms in the presence of oxygen.
In the IR spectrum of Ni(DBOPD) · 2H2O, the dou-
blet band due to the vibration ν(NH) of a secondary
amino group is at 3208 cm–1. The UV region of the
electronic absorption spectrum contains bands at 203,
240, and 280 nm and a low-intensity band at 450 nm;
µeff = 2.92 µB. These data point to a distorted octache-
dral structure of Ni(DBOPD) · 2H2O.
The anisotropic constants g|| = 2.2095, g = 2.053,
and A|| = 191.7 Gs were found from the EPR spectra of
the frozen complex solution in THF.
When the Cu(DBOPD) · H2O solution in CHCl3 is
heated in air, it gradually changes its color to dark
When this complex is heated in methanol in air, it
brown and, then, dark lustrous needle crystals of a new gradually converts into Ni(II) o-phenylene-N,N'-di(sal-
complex precipitate. Analogous transformations of this icylaldiminate), but at a considerably lower rate than in
complex were observed when it was dissolved in THF the case with the Cu(II) compound. The poor solubility
or dioxane and the obtained solutions were allowed to of the nickel complex does not make it possible to
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 27 No. 7 2001

OXIDATIVE DEHYDROGENATION IN COMPLEXES OF TRANSITION METALS
491
quantitatively compare the rates of these processes for
Cu(II) and Ni(II).
Unlike analogous complexes with H2DBED, the
Cu(II) and Ni(II) complexes with H2DBOPD more
readily undergo oxidative dehydrogenation when
exposed to oxygen. Thus, the oxidative dehydrogena-
tion in the case of H2DBED is only observed for the
Co(II) complexes and under very rigid conditions
(60°ë, pyridine), whereas for the Cu(II) and Ni(II)
complexes, dehydrogenation occurs under relatively
mild conditions (30°ë in a polar or weakly polar sol-
vent, such as CH3OH, CHCl3, and others).
The main reason underlying this phenomenon is that
the metal compounds with these ligands have different
capabilities of forming active forms of complexes with
oxygen. The presence of a redox-active Ó-phenylenedi-
amine fragment, which is known to easily donate elec-
trons, can favor the formation of active superoxide and
peroxide complexes even in the case of metals that can-
not give such forms with other ligands.
An attempt to obtain the cobalt complex with
H2DBOPD in air was a failure, and Co(II) Ó-phenylene-
di(salicylaldiminate) always precipitated from the reac-
tion mixture. In an inert atmosphere, Co(DBOPD) pre-
cipitated; however, it is vey difficult to obtain analyti-
cally pure samples because of its sensitivity to oxygen.
Interaction of the M(DBOPD) · 2H2O
Complexes with Oxygen
The Cu(DBOPD) · H2O and Ni(DBOPD) · 2H2O
complexes in the solid state are stable in air; however,
in solutions (methanol, dioxane, tetrahydrofuran), they
undergo oxidative dehydrogenation. For Cu(DBOPD) ·
H2O, the dehydrogenation with a selective formation of
the corresponding Cu(II) Ó-phenylene-N,N'-di(salicyl-
aldiminate) in an atmosphere of pure oxygen occurs at
The mechanism of oxidative dehydrogenation in
a noticeable rate already at 30°ë. The oxidation of the this case is evidently similar to that given above for the
nickel complex occurs at the same rate at a higher tem- Co(DBED) complex and should include the formation
perature (40–45°ë).
of dioxygen adduct:
O
2 NH
NH
NH
N
N
NH
M
M
M
+ O2
O
O
O
O
O
O
13. Mahoney, D.F. and Beattle, J.K., Inorg. Chem., 1973,
REFERENCES
1. Feigl, F. and Furth, M., Monatsh. Chem., 1927, vol. 48,
vol. 12, no. 11, p. 2561.
no. 3, p. 445.
14. Goedken, V.L., J. Chem. Soc., Chem. Commun., 1972,
no. 4, p. 207.
2. Nyholm, R.S., Chem. Rev., 1953, vol. 53, no. 2, p. 263.
3. Bardodej, Z., Collect. Czech. Chem. Commun., 1955,
15. Goto, M., Takeshita, M., and Sakai, T., Inorg. Chem.,
vol. 20, no. 1, p. 176.
1978, vol. 17, no. 2, p. 314.
4. Swartz, G. and Soderberg, R.H., Inorg. Chem., 1968,
16. Goto, M., Takeshita, M., and Sakai, T., Bull. Chem. Soc.
Jpn., 1981, vol. 54, no. 8, p. 2491.
vol. 7, no. 11, p. 2300.
5. McWhinnie, W.R., Miller, J.D., Watts, J.B., and Wad-
dan, D.Y., J. Chem. Soc., Chem. Commun., 1971, no. 12,
p. 629.
17. Goto, M., Takeshita, M., Kanda, N., and Goedken, V.L.,
Inorg. Chem., 1985, vol. 24, no. 4, p. 582.
6. McWhinnie, W.R., Miller, J.D., Watts, J.B., and Wad-
18. Kuroda, Y., Tanaka, N., Goto, M., and Sakai, T., Inorg.
Chem., 1989, vol. 28, no. 11, p. 2163.
dan, D.Y., Inorg. Chim. Acta, 1973, vol. 7, no. 3, p. 461.
7. Diamond, S.E., Tom, G.M., and Taube, H., J. Am. Chem.
Soc., 1975, vol. 97, no. 10, p. 2661.
19. Ferreira da Costa, A.M. and Tome, H.E., J. Chem. Soc.,
Dalton Trans., 1983, no. 9, p. 2051.
8. Brown, G.M., Weaver, T.R., Keene, F.R., and Meyer, T.J.,
Inorg. Chem., 1976, vol. 15, no. 1, p. 190.
20. Yatsimirskii, K.B., Teor. Eksp. Khim., 1986, vol. 22,
no. 3, p. 280.
9. Brown, G.M., Gallahan, R.W., and Meyer, T.J., Inorg.
Chem., 1975, vol. 14, no. 8, p. 1915.
10. Keene, F.R., Salmon, D.H., and Meyer, T.J., J. Am.
Chem. Soc., 1976, vol. 98, no. 7, p. 1884.
11. Yamaguchi, M., Machiguchi, K., Mori, T., et al., Inorg.
Chem., 1996, vol. 35, no. 1, p. 143.
21. Shenk, G.O., Neumuller, O.A., and Eisfeld, W., Ann.
Chem., 1958, vol. 618, no. 1, p. 202.
22. Curtis, N.G., J. Chem. Soc., Chem. Commun., 1966,
no. 23, p. 881.
12. Lane, B.C., Lester, J.E., and Basolo, F., J. Chem. Soc., 23. Vassion, E.G. and Murmann, R.K., Inorg. Chem., 1967,
Chem. Commun., 1971, no. 18, p. 1618. vol. 6, no. 11, p. 2043.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 27 No. 7 2001

492
AIDYN et al.
24. Goedeken, V.L. and Busch, D.H., J. Am. Chem. Soc., 30. Riley, D.P. and Busch, D.H., Inorg. Chem., 1983, vol. 22,
1972, vol. 94, no. 21, p. 7355. no. 26, p. 4141.
25. Goedeken, V.L., Peng, S.-M., and Park, Y.A., J. Chem. 31. Kanatomi, H., Bull. Chem. Soc. Jpn., 1983, vol. 56,
Soc., 1974, vol. 96, no. 1, p. 284. no. 1, p. 99.
26. Weiss, M.C. and Goedeken, V.L., J. Am. Chem. Soc., 32. Matsushita, T. and Shono, T., Bull. Chem. Soc. Jpn.,
1976, vol. 98, no. 11, p. 3389. 1983, vol. 56, no. 3, p. 727.
27. Barefield, E.K., Lovecchio, F.V., Tokel, N.E., et al., 33. Hoshina, G., Tsuchimoto, M., Ohba, Sh., et al., Inorg.
Inorg. Chem., 1972, vol. 11, no. 2, p. 283. Chem., 1998, vol. 37, no. 1, p. 142.
28. Durham, B., Anderson, T.J., Switzer, J.A., et al., Inorg. 34. Medzhidov, A.A., Kasumov, V.T., and Guseinova, M.K.,
Chem., 1977, vol. 16, no. 2, p. 271. Dokl. Akad. Nauk SSSR, 1981, vol. 259, no. 4, p. 866.
29. Dabrowiak, J.C. and Busch, D.H., Inorg. Chem., 1975, 35. Ashley, K.W., Orvig, S., and Orvig, C., J. Chem. Soc.,
vol. 14, no. 8, p. 1881.
Dalton Trans., 1998, no. 18, p. 3049.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 27 No. 7 2001