Copper-mediated imine-nitrile coupling leading to unsymmetric 1,3,5-triazapentadienato complexes containing the incorporated iminoisoindolin-1-one moiety

Article abstract of DOI:10.1039/b805243c

The copper(ii)-mediated integration between various 3-iminoisoindolin-1- ones and neat organonitriles (which play a dual role of solvent and reactant), under heating for ca. 12 h, and without requiring any base, accomplishes the release of the solid (1,3,5-triazapentadienato)Cu^II complexes [Cu{HN=C(R)N=C(C₆R₁R₂R₃R ₄CO)N}₂] (1-11) bearing the incorporated iminoisoindolin-1-one fragment. These compounds were isolated in moderate to good yields (44-78%) and do not require further purification. The iminoisoindolinone-nitrile coupling is Cu^II-mediated and has a general character insofar as it can be efficiently applied for both unsubstituted (R¹-R⁴ = H) and substituted iminoisoindolin-1-ones (R¹, R³, R⁴ = H, R ² = Me; R¹, R⁴ = H, R², R ³ = Cl; R¹-R⁴ = F), and a wide range of nitriles (R = Me, Et, Prⁿ, Prⁱ, C₆H ₁₁, CH₂Ph). Complexes 1-11 were characterized by elemental analyses (C, H, N), FAB⁺-MS, IR spectroscopy, and additionally compounds 1, 2 and 4 by single-crystal X-ray diffraction. The Royal Society of Chemistry 2008.

Full text of DOI:10.1039/b805243c

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Copper-mediated imine–nitrile coupling leading to unsymmetric
1,3,5-triazapentadienato complexes containing the incorporated
iminoisoindolin-1-one moiety†
Maximilian N. Kopylovich,a Konstantin V. Luzyanin,a Matti Haukka,b Armando J. L. Pombeiro*a and
Vadim Yu. Kukushkin*c,d
Received 28th March 2008, Accepted 19th June 2008
First published as an Advance Article on the web 18th August 2008
DOI: 10.1039/b805243c
The copper(II)-mediated integration between various 3-iminoisoindolin-1-ones and neat organonitriles
(which play a dual role of solvent and reactant), under heating for ca. 12 h, and without requiring any
base, accomplishes the release of the solid (1,3,5-triazapentadienato)CuII complexes [Cu{HN=
=
C(R)N C(C6R1R2R3R4CO)N}2] (1–11) bearing the incorporated iminoisoindolin-1-one fragment.
These compounds were isolated in moderate to good yields (44–78%) and do not require further
purification. The iminoisoindolinone–nitrile coupling is CuII-mediated and has a general character
insofar as it can be efficiently applied for both unsubstituted (R1–R4 = H) and substituted
iminoisoindolin-1-ones (R1, R3, R4 = H, R2 = Me; R1, R4 = H, R2, R3 = Cl; R1–R4 = F), and a wide
range of nitriles (R = Me, Et, Prn, Pri, C6H11, CH2Ph). Complexes 1–11 were characterized by elemental
analyses (C, H, N), FAB+-MS, IR spectroscopy, and additionally compounds 1, 2 and 4 by
single-crystal X-ray diffraction.
Introduction
Despite their discovery more than a hundred years ago,1 the
chemistry of 1,3,5-triazapentadienes, which comprise the class
of nitrogen analogues of b-diketones (Scheme 1), is much less
developed as compared to the related oxygen-containing species.2,3
Unlike the other N-derivatives of b-diketones, such as b-
iminoketones and b-diimines (Fig. 1), 1,3,5-triazapentadienes bear
one additional donor site at the central N atom, and recent
DFT calculations2 indicated that 1,3,5-triazapentadienes possess
an even greater potential for sequestering various metal centers
(e.g., CuII, ZnII and PdII) than the related b-diketones.2
Among the 1,3,5-triazapentadiene/ato transition metal com-
plexes, our attention has recently been focused on synthetic
routes leading to copper(II) species. Until now, the experimental
approaches to (1,3,5-triazapentadiene/ato)CuII complexes were
poorly developed, in spite of the fact that some representatives
of this family are known to exhibit intrinsic ferromagnetic
properties.4–7 This can be explained, first of all, by the low
stability of free 1,3,5-triazapentadienes, especially unsubstituted
at the terminal N atoms or monosubstituted species (Fig. 1).
Fig. 1 b-diketones and some of their nitrogen-containing derivatives
(upper row) and 1,3,5-triazapentadienes (bottom row).
Indeed, the reported methods for the preparation of the free
1,3,5-triazapentadienes for further complexation (viz. to a CuII
center) were described mostly for the mono and disubstituted
1,3,5-triazapentadienes containing bulky groups at the terminal
nitrogen atoms and strong electron acceptor and/or sterically
demanded functionalities at the C atoms.1–3,8,9 The known routes
for in situ generation of 1,3,5-triazapentadienes in the course of
template CuII-mediated reactions are not general and include
the hydrolytic conversion of triazine (or 1,3,5-tris(2-pyridyl)-
2,4,6-triazine),10–13 nucleophilic addition of pyrazole to the cyano
group of a dicyanoamidate,14 methanolysis of dicyanamide,15 and
addition of 2-amino-5,5-diphenylimidazolin-4-one to the nitrile
group.16 It is worthwhile noticing that, apart from the latter case, all
examples of (1,3,5-triazapentadiene/ato)CuII complexes obtained
via in situ generation of 1,3,5-triazapentadienes so far documented
include species with exclusively symmetric chelating ligands.
In the framework of our ongoing project on reactions of
metal-activated nitriles17–19 and being interested in the chemistry
aCentro de Qu´ımica Estrutural, Complexo I, Instituto Superior Te´cnico, TU
Lisbon, Av., Rovisco Pais, 1049-001 Lisbon, Portugal. E-mail: pombeiro@
ist.utl.pt
bDepartment of Chemistry, University of Joensuu, Department of Chemistry,
P.O. Box 111, FI-80101, Joensuu, Finland
cSt.Petersburg State University, 198504 Stary Petergof, Russian Federation.
E-mail: kukushkin@VK2100.spb.edu
dInstitute of Macromolecular Compounds of the Russian Academy of
Sciences, V. O. Bolshoi Pr. 31, 199004 St.Petersburg, Russian Federation
† Electronic supplementary information (ESI) available: Characterization
details for compounds 3 and 5–11. CCDC reference numbers 682535–
682537 (1, 2·H2O and 4, respectively). For ESI and crystallographic data
in CIF or other electronic format see DOI: 10.1039/b805243c
5220 | Dalton Trans., 2008, 5220–5224
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Scheme 1 Stepwise versus single-pot approaches for the preparation of the unsymmetric 1,3,5-triazapentadienato complexes.
of 1,3,5-triazapentadiene/ato transition metal complexes derived
from nitrile species,20–25 we recently demonstrated that the prepa-
ration of unsymmetric (1,3,5-triazapentadienato)NiII complexes
might be achieved by either single-pot23 or stepwise25 approaches
(Scheme 1). In the former method,23 3-iminoisoindolin-1-one,
which is generated in situ by an oxime-mediated conversion of
phthalonitrile, interplays with a nitrile at a NiII center, accomplish-
ing the target (1,3,5-triazapentadienato)NiII complexes containing
an incorporated iminoisoindolin-1-one fragment (Scheme 1).
However, we observed that this technique is more specific than
general. Thus, on one hand, it proceeds exclusively at a NiII center,
and all our attempts to expand this single-pot procedure to other
metal centers, in particular to CuII centers, were unsuccessful. On
the other hand, the single-pot route, even in the case of a NiII
center, is limited exclusively to the unsubstituted phthalonitrile
reagent.23
In order to check the generality of the stepwise approach for
the preparation of unsymmetric 1,3,5-triazapentadienato metal
complexes, we attempted to extend the iminoisoindolin-1-one–
nitrile coupling to another metal center, namely to CuII, and report
herein the first example of the preparation of unsymmetric (1,3,5-
triazapentadienato)CuII complexes of a novel type. This study also
shed additional light on the mechanism of the single-pot synthesis
and all these data will be considered in this article.
Fig. 2 Numbering and yields of the (1,3,5-triazapentadienato)CuII
complexes.
Compounds 1–11 were isolated from the reaction medium
by filtration as pale pink or pale brown crystalline solids, in
moderate to good yields (44–78%), and they do not require further
purification. It should be mentioned that the previously reported
stepwise synthesis of (1,3,5-triazapentadienato)NiII complexes25
should be carried out in the presence of triethanolamine as a
base/complexing agent, which plays a crucial role for the success
of the method. In the current study, we found that the synthesis of
(1,3,5-triazapentadienato)CuII species proceeds in a rather efficient
way without triethanolamine. Moreover, the addition of the amine
results in a loss of selectivity and only traces of the target (1,3,5-
triazapentadienato)CuII complexes were detected in a broad and
difficult-to-separate mixture. We anticipate that the CuII center
(behaving as a stronger Lewis acid) provides better electron drift
from the N-coordinated ligands than the NiII center and this makes
the central N site less basic. Hence, it undergoes deprotonation
under the reaction conditions even without requiring the addition
of a base for isolation of the complexes in the unprotonated
form.
Results and discussion
Generation of (1,3,5-triazapentadienato)CuII complexes by
imine–nitrile type coupling
For the preparation of (1,3,5-triazapentadienato)CuII complexes,
a modified stepwise approach reported previously for the
iminoisoindoline–nitrile integration at a NiII-center and yielding
(1,3,5-triazapentadienato)NiII complexes,25 was employed. Hence,
the reaction of 1 equiv. of Cu(OAc)2·H2O with 2 equiv. of the
corresponding unsubstituted or substituted 3-iminoisoindolin-1-
one in neat RCN (acting as both solvent and reactant) under
heating or refluxing for ca. 12 h produces the copper 1,3,5-
triazapentadienato complexes 1–11 (Scheme 1, Fig. 2).
In a blank experiment, a prolonged reflux (48 h) of a mixture
of 1 equiv. of propiononitrile and 2 equiv. of 3-iminoisoindolin-1-
one in CDCl3 showed no resonances in the 1H NMR spectra that
could originate from plausible addition products, and the only new
signals emerged in the spectra belong to phthalimide,26 which was
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Table 1 Crystallographic data for 1, 2·H2O, and 4
2·H2O
generated upon slow hydrolytic degradation of iminoisoindolin-
1-one.27 These observations indicate the CuII-mediated character
of the coupling. We also found that the coupling has a general
character insofar as it is not limited to only the unsubstituted
3-iminoisoindolin-1-one (as in the single-pot approach23), and
can be efficiently applied to iminoisoindolin-1-ones bearing
substituents with various donor/acceptor properties, e.g. 3-
imino-5-methylisoindolin-1-one, 5,6-dichloro-3-iminoisoindolin-
1-one, and 4,5,6,7-tetrafluoro-3-iminoisoindolin-1-one, and also
to a wide range of nitriles (R = Me, Et, Prn, Pri, C6H11, CH2Ph).
1
4
Empirical formula
Formula weight
Temperature/K
C20H16CuN6O2 C22H22CuN6O3 C24H24CuN6O2
435.93
120(2)
482.00
120(2)
492.03
120(2)
˚
l/A
0.71073
Monoclinic
P21/n
0.71073
Monoclinic
C2/c
0.71073
Monoclinic
P21/n
10.7199(7)
5.2390(3)
18.9373(10)
94.191(3)
1060.70(11)
2
1.541
1.066
14 215
2434
Crystal system
Space group
˚
a/A
11.9682(14)
3.8305(5)
19.416(3)
94.224(9)
887.7(2)
2
27.912(2)
4.9750(2)
17.4311(12)
124.989(2)
1983.0(2)
4
˚
b/A
˚
c/A
b/◦
V/A
3
˚
Characterization of the (1,3,5-triazapentadienato)CuII complexes
Z
r
calcd/Mg m-3
1.631
1.614
m(Mo Ka)/mm-1
Number of reflections 7788
1.262
1.142
11 792
The complexes 1–11 were unambiguously characterized by ele-
mental analyses, FAB+-MS and IR spectroscopy, and additionally
complexes 1, 2 and 4 were characterized by single-crystal X-ray
diffraction. The elemental analyses (C, H and N) data are consis-
tent with the proposed formulae of (1,3,5-triazapentadienato)CuII
complexes, containing two 1,3,5-triazapentadienato ligands for
one copper center, with the exception of compound 2, which is
crystallized from the reaction mixture as the monohydrate. The
fast atom bombardment (FAB+) mass spectra of 1–11 contain the
[M]+ or [M + H]+ as the most intense peaks with their characteristic
isotopic distribution.
Unique reflections
1999
2186
0.0524
0.0435
0.1002
Rint
0.0832
0.0456
0.0997
0.0791
0.0397
0.0922
a
R1 (I ≥ 2s)
b
wR2 (I ≥ 2s)
ꢀ
a R1 = ꢀFo| - |Fcꢀ/R|Fo|. b wR2 = {R[w(Fo - Fc2)2]/R[w(Fo2)2]}
.
2
1/2
=
In the IR spectra of 1–11, the C O groups of the
iminoisoindolin-1-one moiety give absorptions in the range of
-1
=
1687–1708 cm , and in the newly formed C NH imine moi-
ety, n(N–H) stretches emerge in the range of 3190–3204 cm-1,
while the corresponding d(N–H) vibrations appear at ca. 1544–
1556 cm-1. One (for 1, 2, 9 and 11) or two (for 3–8, and 10)
=
strong or very strong C N vibrations from the formed imine
moieties and iminoisoindolin-1-one fragment resonate in the
range 1597–1622 cm-1. The medium intensity, weak stretches in
the range of 2851–2989 cm-1 are characteristic of ns(C–H) and
nas(C–H).28 Moreover, the IR spectrum of the monohydrate 2
exhibits the characteristic n(O–H) stretching vibrations with an
absorption maximum at 3447 cm-1. All these values agree with
the corresponding ones for the previously reported symmetric
(1,3,5-triazapentadiene)CuII [3192–3339 cm-1 n(N–H)],4,10–16 and
the unsymmetric (1,3,5-triazapentadiene)NiII complexes [3003–
3186 cm-1 n(N–H), 1523–1563 cm-1 d(N–H)].23,25
Fig. 3 Thermal ellipsoid view of complex 4 with atomic numbering
scheme. Thermal ellipsoids are drawn with 50% probability.
◦
˚
Table 2 Selected bond lengths [A] and angles [ ] for 1, 2·H2O and 4
The X-ray quality crystals of 1, 2 and 4 suitable for single-crystal
X-ray diffraction were obtained upon slow evaporation from
1 : 1 (v/v) methanol–chloroform solutions of the corresponding
1
2
4
◦
complexes in air at ca. 20–25 C. The crystallographic data and
Cu(1)–N(3)
Cu(1)–N(1)
N(3)–C(10)
N(1)–C(8)
O(1)–C(1)
N(2)–C(8)#1
N(2)–C(10)
N(3)–Cu(1)–N(1)
C(8)#1–N(2)–C(10)
1.921(3)
2.023(3)
1.280(5)
1.371(4)
1.222(4)
1.305(4)
1.386(5)
93.15(12)
1.927(2)
2.027(2)
1.310(4)
1.380(3)
1.227(3)
1.301(3)
1.390(4)
92.47(10)
1.924(2)
2.019(2)
1.295(3)
1.373(3)
1.222(3)
1.307(3)
1.371(3)
92.62(8)
processing parameters are summarized in Table 1, while one
representative plot (for complex 4) can be found in Fig. 3, and
bond lengths and angles for all the three complexes numbered in
the same way are given in Table 2.
The crystal structure of each compound (1, 2 and 4) con-
sists of discrete molecules. The structural analysis reveals that
each of the CuII centers in 1–3 adopts a slightly distorted
square-planar geometry, and these minor distortions are indi-
cated by the trans-position angles N(3)–Cu(1)–N(3#) (180.0◦),
N(1)–Cu(1)–N(1#) (180.0◦), and the cis-position angles N(1)–
Cu(1)–N(3)/N(1#)–Cu(1)–N(3#) (varies from 87.5–93.2◦), and
N(3)–Cu(1)–N(3#)/N(3)–Cu(1)–N(3#) (varies from 86.7–92.25◦)
around CuII, which are very close to 180.0 and 90.0◦, respectively.
120.5(3)
120.9(2)
120.7(2)
Symmetry transformations used to generate equivalent atoms: 1: #1 -x,
-y, -z, 2·H2O: #1 -x, -y, -z + 1, 4: #1 -x + 1, -y, -z + 2.
As can be inferred from an inspection of Fig. 3, the copper(II)
center is coordinated to four nitrogen atoms from two similar
negatively charged 1,3,5-triazapentadienato ligands forming two
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◦
˚
Work focusing on widening the family of unsymmetric 1,3,5-
triazapentadiene/ato complexes (e.g., to PdII, PtII metal centers) is
currently under way in our group.
Table 3 Hydrogen bonding parameters: bond lengths [A] and angles [ ]
for 1, 2·H2O and 4
D–H ◊ ◊ ◊ A
d(D–H) d(H ◊ ◊ ◊ A) d(D ◊ ◊ ◊ A) <(DHA)
1
2
N(3)–H(3N) ◊ ◊ ◊ O(1) 0.83(4)
O(2)–H(2O) ◊ ◊ ◊ N(2) 1.00
N(3)–H(3N) ◊ ◊ ◊ O(1) 0.99
N(3)–H(3N) ◊ ◊ ◊ O(1) 0.95
1.97(4)
2.06
1.81
2.727(4)
3.050(3)
2.697(3)
2.741(3)
152(3)
167.5
147.4
148.5
Experimental
Materials and instrumentation
4
1.89
Solvents, copper(II) acetate monohydrate and all organonitriles
were obtained from commercial sources and used as received.
Iminoisoidolin-1-ones were prepared in accordance with a pre-
viously reported procedure.27 C, H and N elemental analyses
were carried out by the Microanalytical Service of the Instituto
Superior Te´cnico. FAB+ mass spectra were obtained on a Trio
2000 instrument by bombarding 3-nitrobenzyl alcohol (NBA)
matrices of the samples with 8 keV (ca. 1.28 ¥ 1015 J) Xe atoms.
Mass calibration for data system acquisition was achieved using
CsI. Infrared spectra (4000–400 cm-1) were recorded on a Bio-Rad
FTS 3000MX instrument in KBr pellets.
six-membered metallacycles. In the latter case, N(1)–C(8) (1.371(4)
for 1, 1.380(3) for 2, and 1.373(3) for 4), and N(2)–C(10) (1.385(5)
for 1, 1.390(4) for 2, and 1.371(3) for 4) are characteristic single
bonds, while C(8)–N(2) (1.305(4) for 1, 1.301(3) for 2, and 1.307(3)
for 4) and C(10)–N(3) (1.280(5) for 1, 1.310(4) for 2, and 1.295(3)
for 4) are typical double bonds. These observations on the discrete
single and double bonds within the 1,3,5-triazapentadienato rings
undoubtedly prove the absence of a delocalized p-bonding system,
as it was previously observed in the related symmetric (1,3,5-
triazapentadienato)CuII complexes.10–16 The C O bond distance
=
from the iminoisoindolin-1-one ring (C(1)–O(1) 1.222(4) for
X-Ray structure determinations
˚
1, C(1)–O(1) 1.227(3) for 2 and C(1)–O(1) 1.222(3) A for 4,
respectively) is equal to within 3s of the corresponding double
The crystals were immersed in cryo-oil, mounted on a Nylon loop
and measured at a temperature of 120 K. The X-ray diffraction
data were collected by means of a Nonius KappaCCD diffrac-
bond in the structurally relevant aromatic amides, i.e. phthalimide
29
˚
(mean value is 1.219 A ).
The NH groups of the 1,3,5-triazapentadienato ligands have
been found to be engaged in hydrogen bonding with the amide
oxygen atom (N(3) ◊ ◊ ◊ O(1) 2.727(4) for 1, 2.697(3) for 2·H2O and
˚
tometer using Mo Ka radiation (l = 0.71073 A). The Denzo-
Scalepack30 program packages were used for cell refinements and
data reductions. The structures were solved by direct methods
using SIR-9731 or SIR200432 with a WinGX33 graphical user
interface. An empirical absorption correction was applied to all
of the data (SORTAV).34 Structural refinements were carried out
using SHELXL-97.35 In 1, the NH hydrogen atom was located
from the difference Fourier map and refined isotropically. In 2·H2O
and 4, NH hydrogens were also located from the difference Fourier
˚
2.741(3) A for 4), and these hydrogen bonds additionally stabilize
the core of the (1,3,5-triazapentadienato)CuII complexes. More-
over, in 2, one more hydrogen bonding interaction (O(2) ◊ ◊ ◊ N(2)
˚
3.050(3) A) between the hydrogen atom from the intercalated
cell water molecule H(2O) and the nitrogen N2 from the 1,3,5-
triazapentadienato ring of the complex is observed (see Table 3 for
all hydrogen bonding parameters).
map but constrained to ride on their parent atom with Uiso
1.5Uiso(parent atom). The other hydrogen atoms were positioned
=
Concluding remarks
geometrically and were constrained to ride on their parent atoms
˚
(C–H 0.95–1.00 A and Uiso = 1.2–1.5Uiso(parent atom)). The
We have achieved a base-free copper-mediated integration between
iminoisoindolin-1-ones and nitriles yielding novel unsymmetric
(1,3,5-triazapentadienato)CuII complexes, namely those bearing
an incorporated iminoisoindolin-1-one fragment. The delevoped
syntheticmethod operates under relativelymild conditions, affords
pure (1,3,5-triazapentadienato)CuII complexes in moderate to
good yields, and, in contrast to the preparation of the NiII
complexes, does not require the addition of a base.
One should mention that the preparation of the unsym-
metric (1,3,5-triazapentadienato)CuII complexes is not feasi-
ble via the previously reported single-pot approach to (1,3,5-
triazapentadienato)NiII complexes (Scheme 1).23 The plausible
mechanism for the single-pot method consists of at least two
steps, i.e. the oxime-promoted generation of a iminoisoindolin-
1-one from phthalonitrile followed by the coupling of the
iminoisoindolin-1-one and a nitrile at a NiII center.23,25 We
anticipate that the reason for the conspicuous failure of the
single-pot method in case of CuII is, presumably, due to the
inhibition by the copper center of the oxime-promoted generation
of iminoisoindolin-1-one. Alternatively, the in situ generation
of the iminoisoindolin-1-one in the nickel synthesis could be
promoted by an oxime–NiII system rather than by only oxime.
crystallographic details are summarized in Table 1, the selected
bond lengths and angles in Table 2, and hydrogen bonds in Table 3.
Synthetic work
Reaction of Cu(OAc)2·H2O with 3-iminoisoindolin-1-one (or 5-
methyl-3-iminoisoindolin-1-one, or 5,6-dichloro-3-iminoisoindolin-
1-one or 4,5,6,7-tetrafluoro-3-iminoisoindolin-1-one) (2 equiv.)
and RCN. A suspension of copper(II) acetate Cu(OAc)2·H2O
(0.200 g, 1 mmol) in neat RCN (5 mL) was refluxed (R =
Me, Et, Prn, Pri) or heated at 100 ◦C (R = CH2Ph, C6H11)
for 15 min. After this, 3-iminoisoindolin-1-one (or 5-methyl-3-
iminoisoindolin-1-one or 5,6-dichloro-3-iminoisoindolin-1-one or
4,5,6,7-tetrafluoro-3-iminoisoindolin-1-one) (2 mmol) was added
to the formed solution and the reaction mixture was refluxed
(in case of R = Me, Et, Prn, Pri) or heated at 100 ◦C (R =
CH2Ph, C6H11) for ca. 12 h (the reflux/heating time depends on
the boiling point of the solvent). During heating, the color of
the solution turned from bright greenish blue to brownish green,
followed by the release of a pale pink (or pale brown) precipitate.
The latter was filtered off, washed with five 5 mL portions of
acetone, three 5 mL portions of water, then again with five 5 mL
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portions of acetone and dried in air at 20—25 ◦C. Yields range
from 44–78% (see Fig. 2) depending on the solubilities of the
target complexes and corresponding difficulties in their isolation.
The crystals of 1, 2·H2O and 4 that were suitable for single-
crystal X-ray diffraction were obtained upon slow evaporation of
a 1 : 1 methanol–chloroform (v/v) solutions of the corresponding
complexes in air at ca. 20–25 ◦C.
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11 T. Kajiwara, A. Kamiyama and T. Ito, Inorg. Chim. Acta, 2003, 22,
=
[Cu{HN=C(Me)N C(C6H4CO)N}2]
(1). C20H16N6CuO2
1789.
(435.9): calcd C 55.10, H 3.70, N 19.28; found C 55.16, H 3.70,
N 19.45%. FAB+-MS, m/z: 437 [M + H]+. IR (KBr, cm-1): 3195
12 A. Kamiyama, T. Noguchi, T. Kajiwara and T. Ito, Inorg. Chem., 2002,
41, 507.
13 E. I. And Lerner and S. J. Lippard, J. Am. Chem. Soc., 1976, 98, 5397.
14 L.-L Zheng, W.-X. Zhang, L.-J. Qin, J.-D. Leng, J.-X. Lu and M.-L.
Tong, Inorg. Chem., 2007, 46, 9548.
=
(s) n(NH), 2966 (w) nas(CH), 2922 (w) ns(CH), 1704 (vs) n(C O),
1622 (vs) n(C N), 1558 (vs) d(NH).
=
15 R. Norrestam, Acta Crystallogr., Sect. C: Cryst. Struct. Commun.,
1984, 40, 955.
16 M. M. Bishop, L. F. Lindoy, D. J. Miller and P. Turner, J. Chem. Soc.,
Dalton Trans., 2002, 4128.
17 V. Yu. Kukushkin and A. J. L. Pombeiro, Chem. Rev., 2002, 102, 1771.
18 A. J. L. Pombeiro, V. Yu. Kukushkin, in Comprehensive Coordination
Chemistry, ed. A. B. P. Lever, J. A. McCleverty and T. J. Meyer, Elsevier,
UK, 2nd edn, 2004, vol. 1, ch. 1.34, pp. 639–660.
=
[Cu{HN=C(Et)N C(C6H4CO)N}2]·H2O (2·H2O). C22H22-
N6CuO3 (482.0): calcd C 54.82, H 4.60, N 17.44; found C 55.07, H
4.76, N 17.23%. FAB+-MS, m/z: 482 [M]+. IR (KBr, cm-1): 3447
(m–w br) n(OH), 3194 (s) n(NH), 2968 (m-w) nas(CH), 2939 (w)
=
=
ns(CH), 1697 (vs) n(C O), 1616 (vs) n(C N), 1553 (vs) d(NH).
i
=
[Cu{HN=C(Pr )N C(C6H4CO)N}2]
(4). C24H24N6CuO2
19 V. Yu. Kukushkin and A. J. L. Pombeiro, Inorg. Chim. Acta, 2005, 358,
(492.0): calcd C 58.59, H 4.92, N 17.08; found C 58.65, H 4.84, N
16.96%. FAB+-MS, m/z: 493 [M + H]+. IR (KBr, cm-1): 3200 (s)
n(NH), 2966 and 2926 (m–w) nas(CH), 2873 (m) ns(CH), 1700 (s)
1.
20 M. N. Kopylovich, A. J. L. Pombeiro, A. Fischer, L. Kloo and V. Yu.
Kukushkin, Inorg. Chem., 2003, 42, 7239.
21 N. A. Bokach, T. V. Kuznetsova, S. A. Simanova, M. Haukka, A. J. L.
Pombeiro and V. Yu. Kukushkin, Inorg. Chem., 2005, 44, 5152.
22 G. H. Sarova, N. A. Bokach, A. A. Fedorov, M. N. Berberan-Santos,
V. Yu. Kukushkin, M. Haukka, J. J. R. Frau´sto da Silva and A. J. L.
Pombeiro, Dalton Trans., 2006, 3798.
=
=
n(C O), 1616 (s) and 1600 (vs) n(C N), 1544 (vs) d(NH).
The characterization details for compounds 3 and 5–11 are given
in the ESI.†
23 M. N. Kopylovich, M. Haukka, A. M. Kirillov, V. Yu. Kukushkin and
A. J. L. Pombeiro, Chem.–Eur. J., 2007, 13, 786.
24 M. N. Kopylovich, E. A. Tronova, M. Haukka, A. M. Kirillov, V. Yu.
Kukushkin, J. J. R. Frau´sto da Silva and A. J. L. Pombeiro, Eur. J. Inorg.
Chem., 2007, 29, 4621.
25 P. V. Gushchin, K. V. Luzyanin, M. N. Kopylovich, M. Haukka, A. J. L.
Pombeiro and V. Yu. Kukushkin, Inorg. Chem., 2008, 47, 3088.
26 C. J. Pouchert, Aldrich library of 13C and 1H FT NMR spectra, John
Wiley & Sons, Ltd, UK, 2008.
27 K. V. Luzyanin, V. Yu. Kukushkin, M. N. Kopylovich, A. A. Nazarov,
M. Galanski and A. J. L. Pombeiro, Adv. Synth. Catal., 2008, 350, 135,
and references therein.
Acknowledgements
This work has been partially supported by the Fundac¸a˜o para
a Cieˆncia e a Tecnologia (FCT), Portugal, and its POCI 2010
program (FEDER funded). K. V. L. expresses his gratitude
to FCT and the POCI program (FEDER funded), Portugal,
for a fellowship (grant SFRH/BPD/27094/2006) and V. Y. K.
is grateful to the FCT (Cientista Convidado/Professor at the
Instituto Superior Te´cnico, Portugal). This work has also been
supported by the Russian Fund for Basic Research (grants 06-
03-32065 and 08-03-90100) and the Academy of Finland (grant
110465).
28 L. J. Belami. The Infrared Spectra of Complex Molecules, Chapman
and Hall, London 1980.
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30 Z. Otwinowski and W. Minor, Processing of X-ray Diffraction Data
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31 A. Altomare, M. C. Burla, M. C. Camalli, C. Giacovazzo, A.
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5224 | Dalton Trans., 2008, 5220–5224
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