Novel CuII-MII-CuII (M = Cu or Ni) trinuclear and [Na i 2 Cu II 6] hexanuclear complexes assembled by bi-compartmental ligands: Syntheses, structures, magnetic and catalytic studies

Article abstract of DOI:10.1039/c4dt03728f

In the present work, two compartmental ligands H₂L¹ and H₂L² were in situ generated during the syntheses of new trinuclear complexes, [Cu₂Ni(L¹)(2,2′-bpy)₂(NO₃)₂][ClO₄]₂ (5), [Cu₃(L²)(NO₃)₂][ClO₄]₂ (6), and [Cu₃(L²)(NCS)₂(NO₃)]⁺ that co-crystallize in 7 with a [Cu₆(L²)₂Na₂(NO₃)₆(NCS)₄] unit to give the final molecular formula [Cu₆(L²)₂Na₂(NO₃)₆(NCS)₄][Cu₃(L²)(NCS)₂(NO₃)]₂(NO₃)₂·5H₂O (7). The magnetic property studies of 5-7 revealed weak Cu^II-Cu^II ferromagnetic interactions in compound 6 (J_Cu-Cu/k_B = +1.4(1) K) and 7 (J_Cu-Cu/k_B = +1.6) while in intranuclear Cu^II-Ni^II-Cu^II compound 5, the magnetic coupling between two Cu^II ions is switched off by the diamagnetic square planar Ni^II bridge. The catalytic epoxidation of two olefins, namely styrene and cyclooctene, by tert-BuOOH (TBHP) was also explored in the presence of a catalytic amount of 5, 6 or 7 in MeCN. For styrene oxidation, 5 exhibited ～57% styrene epoxide selectively (conversion ～37%) with a TON of about 925 along with benzaldehyde (～43%), whereas 6 exhibited conversion up to ～63% (TON ～ 1575) with a good selectivity towards epoxide (～71%). For compound 7, this conversion is more important (TON ～ 8108) probably due to the presence of more active sites involved in the epoxidation. The concerted path was found to be operative for styrene oxidation while a radical path was suggested for the oxidation of cyclooctene.

Full text of DOI:10.1039/c4dt03728f

View Article Online
View Journal
Dalton
Transactions
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: A. Mahammad, S.
Biswas, A. Dutta, M. Dolai, I. Bhowmick, M. Rouzieres, R. Clerac and A. Panja, Dalton Trans., 2015, DOI:
1
0.1039/C4DT03728F.
This is an Accepted Manuscript, which has been through the
Royal Society of Chemistry peer review process and has been
accepted for publication.
Accepted Manuscripts are published online shortly after
acceptance, before technical editing, formatting and proof reading.
Using this free service, authors can make their results available
to the community, in citable form, before we publish the edited
article. We will replace this Accepted Manuscript with the edited
and formatted Advance Article as soon as it is available.
You can find more information about Accepted Manuscripts in the
Information for Authors.
Please note that technical editing may introduce minor changes
to the text and/or graphics, which may alter content. The journal’s
standard Terms & Conditions and the Ethical guidelines still
apply. In no event shall the Royal Society of Chemistry be held
responsible for any errors or omissions in this Accepted Manuscript
or any consequences arising from the use of any information it
contains.
www.rsc.org/dalton

Page 1 of 14
Dalton Transactions
View Article Online
DOI: 10.1039/C4DT03728F
Journal Name
RSCPublishing
ARTICLE
II
II
II
I
II
Novel Cu ꢀM ꢀCu (M = Cu or Ni) trinuclear and [Na Cu ]
2
6
hexanuclear complexes assembled by biꢀcompartmental
†
Cite this: DOI: 10.1039/x0xx00000x
ligands: syntheses, structures, magnetic and catalytic studies
a
a
a
b,c
b,c
Surajit Biswas, Arpan Dutta, Mala Dolai, Indrani Bhowmick, Mathieu Rouzières, Rodolphe
Received 00th January 2012,
Accepted 00th January 2012
b,c
d
a
Clérac, Anangamohan Panja and Mahammad Ali *
DOI: 10.1039/x0xx00000x
1
2
In the present work, two compartmental ligands H L and H L were inꢀsitu generated
2
2
1
www.rsc.org/
during the syntheses of new trinuclear complexes, [Cu Ni(L )(2,2'ꢀ
bpy) (NO ) ][ClO ] (5), [Cu (L )(NO ) ][ClO ] (6), and [Cu (L )(NCS) (NO )] that
3 3 2 4 2 3 2 3
7 with an [Cu (L ) Na (NO ) (NCS) ] unit to give a final molecular
6 2 2 3 6 4
formula [Cu (L ) Na (NO ) (NCS) ][Cu (L )(NCS) (NO )] (NO ) .5H O(
2
2
2
+
2
3 2
4 2
2
coꢀcrystallizes in
2
2
7
). The
6
2
2
3 6
4
3
2
II
3
II
2
3 2
2
magnetic property studies of
in compound JCuꢀCu kB = +1.4(1) K) and
Ni ꢀCu compound , the magnetic coupling between two Cu ions is switched off by
5ꢀ7 revealed weak Cu ꢀCu ferromagnetic interactions
II
6
(
/
7 (JCuꢀCu/kB = +1.6 while intrinuclear Cu ꢀ
II
II
II
5
II
the diamagnetic square planar Ni bridge. The catalytic epoxidation of two olefins,
namely styrene and cyclooctene, by tertꢀBuOOH (TBHP) were also explored in
presence of a catalytic amount of
exhibited ~57% styrene epoxide selectively (conversion ~37%) with a TON of about
25 along with benzaldehyde (~43%), whereas exhibited conversion up to ~63%
TON ~ 1575) with a good selectivity towards epoxide (~71%). For compound , this
5, 6 or 7 in MeCN. For styrene oxidation, 5
9
6
(
7
conversion is more important (TON ~ 8108) probably due to the presence of more
active sites involved in the epoxidation. The concerted path was found to be operative
for styrene oxidation while a radical path for the oxidation of cyclooctene.
This journal is © The Royal Society of Chemistry 2013
J. Name., 2013, 00, 1-3 | 1

Dalton Transactions
Page 2 of 14
View Article Online
ARTICLE
4DT03728F
DOI: 10.1039Jo/Curnal Name
Introduction
In natural metalloproteins, metal ions are simultaneously assembled
to form effective catalytic systems. These natural systems inspire
1
chemists to expand the area of coordination chemistry and catalysis.
Scheme 1
Previously we reported the synthesis and characterization of
For example, ascorbate oxidase, laccase, ceruplasmin, particulate
methane monooxygenase (pMMO) and others contain unique ꢁꢀOH
trinuclear copper(II) complexes which were structurally modelled by
1
II
1
II
1
II
I
mononuclear (L Cu (1)) and diꢀnuclear L Cu (3), L Cu Cu (4)
2
2
1
using synthetic N or O ligands. The functional models of these
complexes using a multidentate (N O ) compartmental ligand (H L )
4
2
2
1
4,15
enzymes were developed by Stack, Pombeiro and others
demonstrating the ability of triꢀ and polyꢀnuclear copper moieties to
(
Scheme 2).
Herein, we report the synthesis, structural
heterotrinuclear
Ni Cu ] complex (5), a trinuclear [Cu ] complex (6) and an
characterization and magnetic studies of a
3
II
II
II
oxidise C–H bonds. These works extensively demonstrated the
[
2
3
importance of C–H bond oxidation by polynuclear complexes
mimicking multicopper oxidases. Copper species are widely found
in nature as diꢀ, triꢀ or polyꢀnuclear species that catalyze selectively
octanuclear
transition
metal/alkali
metal
complex
2
2
[
Cu (L ) Na (NO ) (NCS) ][Cu (L )(NCS) (NO )] (NO ) .5H O(7).
6
2
2
3 6
4
3
2
3
2
3 2
2
Furthermore, we have also tested all these complexes for epoxidation
of olefins namely styrene and cyclooctene using tertꢀButyl
hydroperoxide (tꢀBuOOH) as terminal oxidant and also explored the
magnetic interactions between the Cu centres of these metal ion
complexes.
4
various oxidation reactions. Although increasing attention has been
paid to the design of Cu complexes with polydentate ligands as
4
,5
II
models of copper oxidases and some mononuclear compounds
6
have been recognized as catalysts for alkane oxidation, the use of
multicopper complexes for such reactions still remains an
unexplored area of research. Our main aims are to find a simple
synthetic method to generate multinuclear copper complexes with N,
Results and discussion
Oꢀpolydentate ligands and to investigate the catalytic activity of Synthesis and Structural description of the complexes.
1
II
II
II
these complexes for the oxidation of alkanes under mild conditions, The heteroꢀtrinuclear complex (L Cu Ni Cu ) (
5
) was derived
1
II
thus extending our interest of alkene functionalization.
from its mononuclear analogue (L Ni ) (2) of Schiffꢀbase
ligand (H L ) while homoꢀtrinuclear complex (L Cu ) (6) was
synthesized from the reaction of Schiffꢀbase ligand (H L ) with
metal ion precursor Cu(ClO ) and Cu(NO ) in 1:1:2 ratio.
Complex [Cu (L ) Na (NO ) (NCS) ][Cu (L )(NCS) (NO )]
NO ) .5H O(7) was prepared by reacting the Schiffꢀbase
3 2 2
ligand (H L ) and metal ion precursor [Cu(bpy)(H O) ](NO )
1
2
II
2
3
The incorporation of main group elements like alkali metal ions in
the transition metal complexes to get transition/nonꢀtransition metal
ion assemblies is also an important field of research, as these may
help to trap water into the crystal lattice to increase the water
solubility of the final assemblies. In addition, the presence of nitrate
ions in the molecular assembly may also be useful for in
vivo generation of nitric oxide (NO) and other reactive nitrogen
oxides that clearly have robust NOꢀlike effects for humans, including
blood pressure reduction, inhibition of platelet aggregation, and
2
2
4
2
3 2
2
2
6
2
2
3 6
4
3
2
3
2
(
2
2
2
2
3 2
in presence of NaSCN.
Single crystal Xꢀray diffraction data reveals that
trinuclear Cu(II)ꢀNi(II)ꢀCu(II) species crystallizing in the P2/c
monoclinic space group. In , the coordination environments
around the centrosymmetrical Cu(II)ꢀNi(II)ꢀCu(II) core are
shown in Fig. 1. The [L ] ligand coordinates to two Cu(II)
metal ions that sandwich a central Ni ion. The two Cu(II) sites
are symmetry related.
Each Cu(II) ion is coordinated by N O donor set of atoms out
of which O4(phenoxido) and N4 (3,5ꢀdimethylpyrazole) from
the parent ligand [L ] , N1 and N2 from bipyridyl ligand and
O1 and O3 from the nitrate ion resulting a distorted octahedral
geometry. The N1, N2, N4 and O1 atoms constitute the
equatorial plane while O3 and O4 occupy the axial Cu(II) sites.
On the other hand, the central Ni(II) ion is coordinated by a
N O donor set of atoms from the parent ligand.
5 is a heteroꢀ
7
vasoprotective activity. Apart from the ability to saturate free
5
ꢀ
coordination sites as a monodentate or chelating ligand, NO3 can
function as a bridge between copper and sodium ions within oneꢀ,
1 2ꢀ
twoꢀ or threeꢀdimensional extended coordination networks. Most
ꢀ
important bridging modes of NO that are observed in the literature
3
8
8
9
have been denoted as µ (A), µ ; (B), syn–synµ ; (C), syn–anti
1
,1
1,1,2
ꢀ1,2
3
3
10
11
µꢀ1,2; (D) and anti–anti µꢀ1,2; (E) [A–Ein Scheme 1]. The
compound 7 contains a rare example of interesting [Na Cu ]
2
6
1 2ꢀ
metal/alkali metal based complexes as only two examples of such
type of complexes with a [NaCu ] moiety are reported from an alkali
4
template assembly of two endꢀon azido bridged dinuclear copper
1
2,13
unit.
2
2
2
| J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 2012

Page 3 of 14
Journal Name
Dalton Transactions
View Article Online
ARTICLE
DOI: 10.1039/C4DT03728F
Scheme 2. Scemetic presentation of synthesis of complexes.
The two N atoms are from imine part (N5 and its symmetry The phenoxido Oꢀatoms are
µꢀbridging type and
equivalent counterpart) and two Oꢀatoms (O4 and its symmetry simultaneously coordinated to Cu1 and Ni1 atoms. There are
1
2ꢀ
equivalent counterpart) from phenoxido group of [L ] , to form two perchlorate anions in the outer coordination sphere to
a square planar coordination sphere around the Ni1 metal ion. balance the total charge. The Cu1ꢀNx distances (x = 1, 2 and 4)
This journal is © The Royal Society of Chemistry 2012
J. Name., 2012, 00, 1-3 | 3

Dalton Transactions
Page 4 of 14
View Article Online
ARTICLE
4DT03728F
DOI: 10.1039Jo/Curnal Name
are ~2.002, 2.009, and 1.996 Å, respectively while Cu1ꢀOx (x =
, 3 and 4) lie in the 1.976 and 2.689 Å range which clearly
1
indicate that the two Cu1 atoms are in highly distorted
octahedral geometry. The square planar Ni1 metal ion fits well
into the ligand cavity with short NiꢀO bond distances of NiꢀO4
~1.857 Å and (Table S1) NiꢀN5 ~1.853 Å.
The single crystal Xꢀray diffraction analysis indicated that
6
is a
homoꢀtrinuclear Cu(II)ꢀCu(II)ꢀCu(II) complex with two
perchlorate anions to balance the charge. It crystallizes in the
monoclinic C2/c space group. In complex 6, the coordination
environment around Cu(II)ꢀCu(II)ꢀCu(II) are shown in Fig. 2
where two terminal Cu(II) (Cu2 and Cu3) metal ions sandwich
the central Cu(II) site (Cu1) as observed in complex
5 with only
1
differences being that the 3,5ꢀdimethyl pyrazole in H L is
2
2
replaced by N,Nꢀbis(2ꢀmethylpyridyl) group in H L .
2
Fig. 2. Molecular view of 6 with coordination atom numbering
scheme. Colour scheme: Green: Cu; Red: O; Blue: N; Orange: C. All
Hꢀatoms are omitted for clarity. a = ꢀx,y,1/2ꢀz.
a
The two phenoxido Oꢀatoms (O1 and O1 ) and two O atoms
a
ꢀ
(
O4 and O4 ) from two NO3 ions are ꢁꢀbridging type. The
geometries around the two terminal Cu metal ions (Cu2 and
a
Cu2 ) are comparable. The Cu2ꢀNx distances (x = 2, 3 and 4;
Table S2) are in the 1.919 to 2.025 Å range while Cu2ꢀOx
distances (x = 1, 3 and 4) fall between 1.970 and 2.776 Å. The
bond distances around the central Cu1 are: Cu1ꢀNx (x = 1 and
a
a
a
1
) ~ 1.927Å and Cu1ꢀOx (x = 1, 1 , 4 and 4 ) ~1.961ꢀ2.600 Å.
The structure of complex Fig. 3) showed that the two
7
(
2
trinuclear [Cu (L )(NCS) ] moieties are connected by a
3
2
2
[
Na (µ ꢀNO ) {
η
ꢀ(µ1,2,3,3ꢀNO ) ] moiety almost in a linear
2
1,2
3 4
3 2
ꢀ
3
fashion by two bridging NO group in a
η ꢀµ ꢀNO mode along
3 3
3
2
+
with a coꢀcrystallized [Cu (L )(NCS) (NO )] cation. One nonꢀ
3
2
3
coordinated nitrate ion is present in the crystal lattice to balance
Fig. 1. Molecular view of 5 with coordination atom numbering
2
the overall charge. In the [Cu (L ) Na (NO ) (NCS) ] assembly
6
2
2
3 6
4
scheme. Colour scheme: Green: Cu; Red: O; Blue: N; Yellow: Ni;
ꢀ
the [Cu ] trinuclear unit is comprised of three Cu atoms Cu1,
3
Orange: C. All Hꢀatoms and ClO are omitted for clarity.
4
Cu2 and Cu3 in three different coordination environments. Cu1
is in octahedral ligand field coordinated by N1, N2, N3 and N9
and lie in the basal plane formed by bisꢀpicolyl unit (N1, N2,
In
6, all the Cu(II) ions are in distorted octahedral geometry.
The two terminal Cu(II) (Cu2 and Cu3) metal ions are
2
2ꢀ
N3) and one thiocyanate (N9) unit, whereas the axial positions
coordinated by N O donor set of atoms from the [L ] ligand
3
3
ꢀ
are occupied by O1 (phenoxo) and O16 (NO ). The central
along with two nitrato anions. The Cu2 is coordinated by three
N atoms (N2, N3 and N4) from the bisꢀpicolylamine, one
phenoxo O atom (O1) and two O atoms (O3 and O4) from one
3
Cu2 atom is in square planar geometry coordinated by N4, N5
2
2ꢀ
(
imino), O1 and O2 (phenoxido) coming from the [L ] ligand.
a
Lastly, the terminal Cu3 metal ion is in square pyramidal
geometry, the equatorial plane being occupied by N6, N7, N8
nitrate anion and likewise Cu2 (symmetry operator a = ꢀx,y,1/2ꢀ
a
a
a
z) is coordinated by three N atoms (N2 , N3 and N4 ) from the
a
(
bisꢀpicolyl amine) and N10 (thiocyanate) atoms. The sole axial
bisꢀpicolylamine, one phenoxo Oꢀatom (O1 ) and two O atoms
O3 and O4 ) from one nitrate anion to form the distorted
a
a
position is occupied by O2 (phenoxo) atom. The central sodium
(
+
unit consists of two Na ions in heptaꢀcoordinating (O ) ligand
octahedral geometry. On the other hand, the central Cu(II)
ion(Cu1) is coordinated by N O donor set of atoms O1 and
7
+
field with four
µꢀNO ions mutually connecting two Na ions. In
3
addition, there are two η ,µ ꢀNO groups connecting two Na
2
4
2
+
a
a
ꢀ
O1 from two phenoxido groups, O4 and O4 from µ1,1,2ꢀNO3
ion and N1 and N1 from the ligand [L ] .
3
3
a
2 2ꢀ
ions along with Cu1 of the suitably faced Cu trinuclear units in
3
a
topology
similar
to
that
is
observed
in
[
2
Na Cu (bemp) (OH) (NO ) (OH ) ]·5H O (
1·5H O; H bemp:
2
4
2
2
3 2
2 4
2
2
3
1
6
,6ꢀbisꢀ[(2ꢀhydroxyethylimino)ꢀmethyl]ꢀ4ꢀmethylꢀphenol). In
2
+
the coꢀcrystallized [Cu (L )(NCS) (NO )] cation, the three
3
2
3
Cu(II) metal ions, Cu4, Cu5 and Cu6, have a coordination
4
| J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 2012

Page 5 of 14
Journal Name
Dalton Transactions
View Article Online
ARTICLE
DOI: 10.1039/C4DT03728F
2
+
environment similar to those observed in the [Cu (L )(NCS) ] being additionally coordinated to two Na ions as in [Na Cu ]
3
2
2
6
part of the [Na Cu ] complex and compared well as Cu1≅Cu4, complex. All the important bond lengths and bond angles are
2
6
Cu2≅Cu5 and Cu3≅Cu6. Here the Cu4 differs from Cu1 only reported in Table 1 and compared to the values commonly
ꢀ
17ꢀ19
from the fact that the NO anion is terminal in nature instead of observed for such types of coordination species.
3
Table 1Selected Bond lengths (Å) and bond angles (º) of 7
Bond length(Å)
O14 ꢀNa1 ꢀO15
N12 ꢀCu4 ꢀN20
O1 ꢀCu2 ꢀN4
N13 ꢀCu4 ꢀN20
O1 ꢀCu2 ꢀN5
O3 ꢀCu4 ꢀO5
O1 ꢀCu2 ꢀN9
O3 ꢀCu4 ꢀN11
O2 ꢀCu2 ꢀN4
O3 ꢀCu4 ꢀN12
O2 ꢀCu2 ꢀN5
O3 ꢀCu4 ꢀN13
O2 ꢀCu2 ꢀN9
O3 ꢀCu4 ꢀN20
N4 ꢀCu2 ꢀN5
N15 ꢀCu5 ꢀN19
N4 ꢀCu2 ꢀN9
N14 ꢀCu5 ꢀN19
N5 ꢀCu2 ꢀN9
N14 ꢀCu5 ꢀN15
O2 ꢀCu3 ꢀN6
O3 ꢀCu5 ꢀO4
O2 ꢀCu3 ꢀN7
O3 ꢀCu5 ꢀN14
O2 ꢀCu3 ꢀN8
O3 ꢀCu5 ꢀN15
O3 ꢀCu5 ꢀN19
O11 ꢀNa1 ꢀO14
O4 ꢀCu5 ꢀN14
O4 ꢀCu5 ꢀN15
O4 ꢀCu5 ꢀN19
Cu1 ꢀO1 ꢀCu2
52.1(2)
97.7(3)
92.6(3)
173.6(3)
159.5(3)
171.6(3)
78.1(2)
91.1(3)
158.6(3)
98.9(3)
93.2(3)
87.8(3)
94.8(2)
85.8(3)
85.2(3)
88.6(3)
106.2(3)
102.0(3)
83.0(3)
83.6(4)
99.9(3)
94.2(2)
90.7(3)
162.9(3)
93.7(3)
93.5(3)
94.8(3)
149.0(4)
93.2(3)
163.5(3)
76.2(2)
103.4(2)
Cu1 ꢀO1
Cu6 ꢀN16
Cu1 ꢀO16
Cu6 ꢀN17
Cu1 ꢀN1
Cu6 ꢀN18
Cu1 ꢀN2
Cu6 ꢀN19
Cu1 ꢀN3
Cu1 ꢀN9
Cu2 ꢀO1
Cu2 ꢀO2
Cu2 ꢀN4
Cu2 ꢀN5
Cu2 ꢀN9
Cu3 ꢀO2
Cu3 ꢀN6
Cu3 ꢀN7
Cu3 ꢀN8
Cu5 ꢀO4
Cu5 ꢀO3
Cu6 ꢀO4
Cu5 ꢀN14
Cu3 ꢀN10
Cu4 ꢀN20
Cu4 ꢀN13
Cu4 ꢀO5
Cu4 ꢀN11
Cu4 ꢀO3
Cu4 ꢀN12
Cu5 ꢀN15
2.389(6)
1.984(7)
2.582(8)
2.030(6)
1.984(8)
1.997(8)
2.056(8)
1.954(8)
1.955(9)
1.949(8)
1.923(6)
1.906(6)
1.908(8)
1.929(8)
2.870(8)
2.319(6)
1.994(9)
2.029(9)
2.001(8)
1.912(5)
1.907(7)
2.348(6)
1.921(8)
1.949(9)
1.968(9)
2.052(8)
2.463(15)
1.983(8)
2.463(7)
1.985(8)
1.926(8)
Cu5 ꢀN19
Na1 ꢀO8
2.863(8)
2.465(8)
2.462(9)
2.330(11)
2.500(8)
2.389(9)
2.342(7)
O4 ꢀCu6 ꢀN18
Cu2 ꢀO2 ꢀCu3
N11 ꢀCu4 ꢀN13
N2 ꢀCu1 ꢀN9
N11 ꢀCu4 ꢀN20
N3 ꢀCu1 ꢀN9
91.4(3)
109.0(3)
83.2(3)
179.5(4)
97.5(4)
96.8(3)
82.7(3)
96.1(2)
83.7(3)
162.0(3)
96.7(3)
83.6(3)
179.4(3)
90.0(2)
96.6(3)
81.9(3)
101.2(3)
96.1(3)
104.1(4)
90.9(3)
111.3(3)
92.3(3)
133.5(3)
120.8(4)
89.8(3)
51.7(3)
104.0(4)
83.4(3)
118.3(3)
99.6(4)
129.5(3)
82.1(3)
Na1 ꢀO10
Na1 ꢀO11
Na1 ꢀO14
Na1 ꢀO15
Na1 ꢀO14a
N12 ꢀCu4 ꢀN13
O1 ꢀCu2 ꢀO2
Bond angles (°)
O1 ꢀCu1 ꢀO16
O2 ꢀCu3 ꢀN10
O1 ꢀCu1 ꢀN1
N6 ꢀCu3 ꢀN7
O1 ꢀCu1 ꢀN2
N6 ꢀCu3 ꢀN8
O1 ꢀCu1 ꢀN3
N6 ꢀCu3 ꢀN10
O1 ꢀCu1 ꢀN9
N7 ꢀCu3 ꢀN8
N7 ꢀCu3 ꢀN10
O16 ꢀCu1 ꢀN2
N8 ꢀCu3 ꢀN10
O16 ꢀCu1 ꢀN3
O5 ꢀCu4 ꢀN11
O16 ꢀCu1 ꢀN9
O5 ꢀCu4 ꢀN12
N1 ꢀCu1 ꢀN2
O5 ꢀCu4 ꢀN13
N1 ꢀCu1 ꢀN3
O5 ꢀCu4 ꢀN20
N1 ꢀCu1 ꢀN9
N11 ꢀCu4 ꢀN12
N2 ꢀCu1 ꢀN3
172.8(2)
91.5(3)
91.6(3)
83.3(3)
89.6(3)
161.2(4)
97.1(3)
95.9(4)
90.9(3)
83.7(4)
177.7(4)
92.7(3)
96.6(4)
89.9(3)
80.7(4)
86.8(3)
88.5(3)
83.6(3)
89.1(4)
164.1(3)
97.3(4)
96.4(3)
162.3(4)
83.2(3)
N16 ꢀCu6 ꢀN17
N16 ꢀCu6 ꢀN18
N16 ꢀCu6 ꢀN19
N17 ꢀCu6 ꢀN18
N17 ꢀCu6 ꢀN19
O4 ꢀCu6 ꢀN17
Na1 ꢀO14 ꢀNa1_a
O16 ꢀCu1 ꢀN1
O4 ꢀCu6 ꢀN16
N18 ꢀCu6 ꢀN19
O8 ꢀNa1 ꢀO11
O8 ꢀNa1 ꢀO14
Cu4 ꢀO3 ꢀCu5
O8 ꢀNa1 ꢀO15
O8 ꢀNa1 ꢀO14_a
O10 ꢀNa1 ꢀO11
O10 ꢀNa1 ꢀO14
O8 ꢀNa1 ꢀO10
O11 ꢀNa1 ꢀO14_a
O14 ꢀNa1 ꢀO14_a
O14_a ꢀNa1 ꢀO15
O11 ꢀNa1 ꢀO15
O10 ꢀNa1 ꢀO15
O10 ꢀNa1 ꢀO14a
Symmetry operators: x,y,z; ꢀx,ꢀy,ꢀz.
This journal is © The Royal Society of Chemistry 2012
J. Name., 2012, 00, 1-3 | 5

Dalton Transactions
Page 6 of 14
View Article Online
ARTICLE
4DT03728F
DOI: 10.1039Jo/Curnal Name
is thus the simple sum of the Curie contributions from the two
II
II
S
= ½ Cu centers with a g factor of about 2.2(1). The two Cu
Fig. 3. (a) Molecular view of 7 with colour scheme: Green: Cu,
Red: O, Blue: N, Yellow: S, Violet: Na, Orange: C atoms. All Hꢀ
atoms, Nitrate counter anion, one trinuclear unit and water of
crystallization are omitted for clarity.
Fig. 4. UVꢀVis spectra of complexes 5, 6 and 7 in MeCN. [c] = 1.0
The Cu1ꢀN9 (NCS) and Cu2ꢀN9 distances are found to be
ꢀ3
ꢀ5
x 10 M for dꢀd bands at longer wavelengths and [c] = 1.0 x 10
M
1
.950 and 2.870 Å, respectively indicating a discrete Cu1ꢀN9
for ILCT/MLCT bands at shorter wavelengths
.
bond while only Cu2ꢀN9 semiꢀbond is observed.
a
Nevertheless the NCS ligand can be considered as a bridging
ligand as also observed for the coꢀcrystallizing
centers are quite well separated from each other in the crystal
structure and thus no significant interꢀmolecular shortꢀcontacts
are observed. Accordingly, the field dependence of the
magnetization (Fig. S1) exhibits a saturation at 1.83 K under 7
2
+
[
Cu (L )(NCS) (NO )] cation with Cu6ꢀN18 = 1.954 Å and
3 2 3
Cu5ꢀN18 = 2.862 Å. The neighboring Cu···Cu separations in
the trinuclear fragments fall in the 3.395ꢀ3.622 Å range,
whereas the Na···Na distance is 3.612 Å.
T for which it reaches 2.27 ꢁB as expected for two isolated
S =
½
spins. The fit of M vs H
/
T
data at 1.83 K (Fig. S1) as a sum
of two
allows an estimation of the
centers consistently with the
S = ½ Brillouin functions works perfectly well and
UVꢀVis spectroscopy
II
g
factor around 2.24(6) for the Cu
g value evaluated from the Curie
The electronic spectra of complexes 5ꢀ7 were recorded in
MeCN (Fig. 4). The electronic transition band appears at 345
constant (vide supra).
5
3
ꢀ
nm with a molar extinction coefficient (
ε
) 1.87 x 10 dm mol
corresponding to an ILCT/MLCT band.
, bands are located at 633 and 364 nm with
1
ꢀ1
cm for complex
For complex
values of 302 and 1.9 x 10 dm mol cm respectively while
the corresponding bands for complex appear at 604 and 360
nm with values of 894 and 2.3 x 10 dm mol cm
5
6
ε
5
3
ꢀ1
ꢀ1
7
5
3
ꢀ1
ꢀ1
ε
respectively. The bands at longer wavelengths may be
attributed to the dꢀd transitions while bands at shorter
wavelengths (345, 360 and 364 nm) are due to intraꢀligand
or/and metalꢀligand chargeꢀtransfer transitions.
Magnetic properties
The temperature dependence of magnetic susceptibility for
complexes 5ꢀ7 have been measured at 1000 Oe between 1.8
Fig. 5. The
χT vs T plots of complexes 5ꢀ7 between 1.8 and 290 K
and 290 K (Fig. 5). Considering the symmetry in the crystal
at 1000 Oe (with
χ
defined as the magnetic susceptibility equal to
II
structure of 7, the magnetic data are normalized for six Cu
M/H per mole of complex). The hollow circles are the experimental
data and the red solid lines are the best fit of the experimental data
for 6 and 7 as described in text.
II
II
II
centers with two different trinuclear Cu ꢀCu ꢀCu fragments
while for and , the magnetic data are normalized per two
and three Cu(II) sites respectively. At room temperature, the
5
6
3
χ
T
product of
5
is 0.90 cm K/mol. This value does not change
II
II
II
Both complexes
species and their corresponding
6
and
7
consist of trinuclear Cu ꢀCu ꢀCu
products at 290 K, 1.28 and
6 and 7 respectively, are in agreement with
with lowering of the temperature indicating the Curieꢀtype
χ
T
8
II
paramagnetism of complex
5
. The 3d square planar Ni center
3
2
.20 cm K/mol for
three (for ) and six (for
with average values of 2.1(1) for
is as expected diamagnetic and provide a good isolation of the
II
6
7
) Cu magnetic centers respectively
and 2.0(1) for . With
II
3
two paramagnetic Cu sites. The χT product of 0.90 cm K/mol
g
6
7
6
| J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 2012

Page 7 of 14
Journal Name
Dalton Transactions
View Article Online
ARTICLE
DOI: 10.1039/C4DT03728F
lowering of temperature, both
χT products remain almost the
same until about 30 K and then increases to reach 1.72 and
3
2
.96 cm K/mol at 1.8 K for 6 and 7 respectively. This thermal
behavior indicates without ambiguity the presence of
ferromagnetic interactions in both complexes between the
II
Cu centers of the trinuclear species. In order to probe the
II
exchange between the
S
= ½ Cu sites, the magnetic coupling
Scheme 3
II
II
between the two terminal Cu spins and the central Cu one
are considered, as a first approximation, to be the same in all
the trinuclear moieties. A lowꢀfield analytical expression of the
magnetic susceptibility of
following Heisenberg
SCu1 SCu2 SCu2 SCu3) where
coupling. This simple model reproduce perfectly the
experimental vs data at 1000 Oe (solid red lines in Fig. 5
with the following sets of parameters: kB = +1.4(1) K with
2.1(1) for and kB = +1.6(3) K with = 2.0(1) for . In
addition, the field dependence of the magnetization of and
were also collected in the 1.8 – 8 K range (Fig. S2). At 7 T and
.83 K, the magnetization saturates at 3.25 ꢁB for which is
expected for three = ½ spins or an ST = 3/2 spin system (gav
.17(5)), and it saturates near 5.70 ꢁB for consistent with six
= ½ spins or two ST = 3/2 spin systems (gav = 1.90(5)).
6
and
spin
7
have been deduced from the
Hamiltonian:
J is the average Cu ꢀCu
H
=
ꢀ
II
II
2
J(
•
+
•
χ
T
T
)
J/
g
=
6
J/
g
7
6
7
1
6
S
=
2
7
S
Fig. 6. %Conversions of styrene and cyclooctene at different
reaction times in liquid phase partial oxidation by 7.
Catalytic activities
In the present report we have explored the catalytic
epoxidation of two olefins, namely styrene and cyclooctene by
t
ꢀBuOOH in presence of a catalytic amount of Schiffꢀbase
complexes and in MeCN. The results of the catalytic
oxidation of different substrates are given in Table 2and
shown in Scheme 3. Using complex as catalyst, under
homogeneous conditions, the styrene oxidation with ꢀBuOOH
5
,
6
7
5
t
gives ~57% styrene epoxide selectively (conversion ~37%)
with a TON ~925 (TONs: turn over numbers = moles of
substrate converted per mole of Cu) (Table 2) along with a
moderate amount of benzaldehyde (~45%). Besides, the
Fig. 7. Comparison of styrene conversion at different reaction times
in liquid phase partial oxidation by 5, 6 and 7.
corresponding conversion using the complex
63% (TON ~ 1575) with a good selectivity towards epoxide
~71%) while for complex , the conversion became much
more efficient and the corresponding TON reaches ~8108;
likely because of the presence of more active sites in
involved during the transformation to epoxide. When
cyclooctene is used as substrate, complex exhibits an
6 increases to
~
(
7
7
6
excellent conversion of ~71% (Table 2) with ~78% selectivity
for cyclooctene oxide. Apart from cyclooctene oxide,
cyclooctaneꢀ1,2ꢀdiol (~15%) was also generated owing to
hydrolysis of the epoxide. When complex
conversion drastically falls down to ~46% with epoxide
selectivity of ~74%; on the other hand in case of complex
significant increase in % conversion, selectivity and TON is
observed.
5 is used, the
7
a
Fig. 8. Comparison of cyclooctene conversion at different reaction
time in liquid phase partial oxidation by 5, 6 and 7.
This journal is © The Royal Society of Chemistry 2012
J. Name., 2012, 00, 1-3 | 7

Dalton Transactions
Page 8 of 14
View Article Online
ARTICLE
4DT03728F
DOI: 10.1039Jo/Curnal Name
a
Table 2.Homogeneous catalytic epoxidation of olefins by tꢀBuOOHcatalysed by compounds 5ꢀ7 in MeCN, [Substrate] = 50 mmol,
temperature 55 °C
b
c
Catalyst
Substrate
Styrene
Reaction time Conversion
h)
% yield of products
TON (TOF)
(
Epoxide
36
Others
5
3
6
9
3
64
46
41
39
43
2
1mg (0.016 mmol)
13
24
29
37
54
59
61
57
1
2
2
4
925(75)
Cyclooctene
3
6
9
5
70
72
75
78
74
30
28
25
22
26
15
29
34
46
1
2
2
4
1150(88)
6
Styrene
3
6
9
8
70
73
76
74
71
30
27
24
26
29
2
1 mg (0.017 mmol)
15
36
49
63
1
2
2
4
1575 (120)
Cyclooctene
3
6
9
9
77
79
81
84
78
66
68
72
75
68
23
21
19
16
22
34
32
28
25
32
17
40
58
71
14
19
27
49
75
1
2
2
4
1775 (142)
8108 (552)
7
Styrene
3
6
9
1
8 mg (0.0037 mmol)
1
2
2
4
Cyclooctene
3
6
9
16
23
33
57
81
79
81
82
86
83
21
19
18
14
17
1
2
2
4
8756 (642)
a
b
c
3
Solvent: CH CN; temperature: 60°C. TON: turn over number = moles of substrate converted per mole of Cu. TOF: turnover frequency = moles of substrate converted per mole of
Cu center per hour measured in 12 hours.
Table 3.Comparison of the catalytic efficiency of 5, 6 and 7 with other reported copper(II) catalysts for the styrene epoxidation with tꢀ
BuOOH in MeCN in 24 hours.
Catalyst
O)](ClO
Conversion (%)
Epoxide selectivity(%)
TON [TOF]
[69]
Ref.
4(k)
4(k)
4(k)
4(l)
4(l)
20
21
21
21
21
15
15
1
[
[
[
[
Cu(L )(H
2
4
)
86
75
99
100
100
88
85
88
83
81
70
68
37
63
75
42
54
39
86
58
90
90
89
88
92
53
52
57
71
68
2
Cu(L )]
[60]
[79]
[252]
[158]
264
[4.2]
[4.4]
[4.1]
[4]
280
272
925[75]
1575[120]
8108[552]
3
Cu(L )]
1
Cu(HL )(NO
3
)]
n
{
[Mg(H
2
O)
6
][Cu(pydca)
2
].2H
2
O}
n
[
[
[
[
[
Cu
2
4
4
4
4
L(µ1,1ꢀN3)(µ1,3ꢀN3)(µ1,1
,
1
ꢀN3)]
1
a
Cu
Cu
Cu
Cu
(O)(L )
(O)(L )
(O)(L )
(O)(L )
2
2
2
2
(CH
(CH
(CH
(CH
3
3
3
3
COO)
COO)
COO)
COO)
4
4
4
4
]
2
a
].CH
3
CN
3
a
]
4
a
]
3
4
5
6
7
This work
This work
This work
a
.
H O was used as terminal oxidant
2 2
Fig. 6 displays the
styrene and cyclooctene at different reaction times in liquid presented in Fig. 7 and
phase partial oxidation catalyzed by whereas the relative are epoxides and the selectivity for these products are relatively
efficiencies of the catalysts are given in Fig. S3 for complex high. The high TONs obtained for the substrates suggest a very
%
conversions and epoxide selectivity of As observed from the results listed in Table 2 and graphically
8
, the major products of the reactions
7
5
and Fig.S4 for complex 6.
good catalytic efficiency of these complexes in presence of tꢀ
BuOOH as oxidant. We have also calculated the turnover
8
| J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 2012

Page 9 of 14
Journal Name
Dalton Transactions
View Article Online
DOI: 10.1039/C4DT
A
03
R
7
T
2
I
8
C
F
LE
II
frequency (TOF) for the conversion of styrene/cyclooctene for According to the mechanistic proposal (Scheme 4) LCu
the period of 12 hours where almost linear dependence of (adopted to represent the catalyst in simple way) converts
tꢀ
•
conversion with time is prevailing and found to be: 77/88, BuOOH into
20/142, 552/642 using complex respectively. The huge there occurs a reductive cleavage of the peroxide bond of
difference of conversion during the epoxidation reactions BuOOH by LCu to form
catalyzed by and may be due to the different number of turn, rapidly abstracts a hydrogen atom from
central metal ions present in the complexes. The large more thermodynamically stable
tꢀBuOO by two pathways. In the first pathway
1
5
,
6
,
7
tꢀ
II
•
III
•
t
ꢀBuO and LCu (OH). The
tꢀBuO in
ꢀBuOOH to form
ꢀBuOO . Now one electron
tꢀBuOOH by LCu (OH) completes the catalytic
5
,
6
7
t
•
25
t
III
difference in catalytic efficiency between complexes
may be attributed to the fact that the Ni metal ion in complex
5
and
6
5
oxidation of
•
cycle with the formation of the second
t
ꢀBuOO and H O and
2
II
either remains silent or takes poorly part to the catalytic activity regenerates LCu . Thus, in one complete catalytic cycle three
compare to the Cu metal ions in complex
may be mentioned here that [Ni(L )] does not show any one mole of water, and two moles
catalytic effect on such epoxidation reactions. In case of radical thereby generated now reacts with cyclooctene to
6
. In this context, it mole of
t
ꢀBuOOH are used up to generate one mole of
t
t
ꢀBuOH,
ꢀBuOO
1
•
•
tꢀBuOO . The
2
0
complex
complex
7
5
, the large number of active centers compared to generate cycloocteneꢀoxide, which may undergo hydrolysis to
and is likely responsible for its enhanced catalytic form cyclooctaneꢀ1,2ꢀdiol as outlined in Scheme 4a
6
.
efficiency. The order of catalytic efficiency follows the order
and may be attributed to the cooperative effect i.e., with
5<6<7
the increase in catalytic site the efficiency increases. In case of
styrene, the epoxide formed undergoes further oxidation to
form benzaldehyde (~40%) with an equivalent amount of
formaldehyde. The yield of CH O was measured by mixing
2
equal volumes of the solutions to be analyzed and acetylacetone
in an acetic acid–ammonium acetate buffer medium and
measuring the absorbance at 410 nm and comparing it with the
standard calibration curve constructed by reacting equal
volumes of different known concentrations of CH O and
2
2
1
acetylacetone under the similar reaction conditions.
It is worth noting that a blank reaction of the oxidation of
Scheme 4a
*
cyclooctene in the absence of any catalyst under identical
reaction conditions showed very poor conversion (~ 8%) and
epoxide selectivity, thereby confirming the catalytic role of the
Cu complexes in these epoxidation reactions.
There are only few reports on the epoxidation of olefins
catalyzed by polynuclear Cu(II)ꢀSchiff base complexes where
2
2
TONs were found to be in the 160ꢀ290 range and TOFs were
in 5ꢀ17 range for heterogeneous condition and 2.2ꢀ6.0 for
2
3
homogeneous conditions (Table 3). To the best of our
knowledge, our systems showed the highest TON/TOF values
for Cu(II)ꢀSchiff base complexes under homogeneous reaction
conditions. In solution, the existence of trinuclear species for all
the complexes
S5). However, in case of complex
expected molecular ion peak even using very low cone
potential. Rather undergoes fragmentation to give ESIꢀ
6
and
7
were confirmed by HRMS analysis (Fig.
5
, we failed to get the
5
+
1
+
Scheme 4b
MS (m/z) as: 569.2297([Ni(L )+H ]); 280.9750 ([Cu(bpy)ꢀ
NO )]) (Fig. S5). It was also observed that the catalysts remain
(
3
A tentative concerted nechanism of the epoxidation of styrene can
be framed as outlined in Scheme 4b for cyclooctene.As revealed
intact even after the completion of 2ꢀ3 catalytic cycles.
The epoxidation reactions are typically believed to operate
II
2
4
from Scheme 4b, the catalysts, designated as LCu , takes up tꢀ
either through a radical or concerted pathway. In order to
ascertain which one is operative, we decided to carry out
epoxidations in the presence of potential radical scavengers like
II
t
BuOOH to form LCu •••OOBu adduct which further coordinates to
styrene to bring the oxidant and the substrate closer to each other.
Now this adducts leads to the formation of epoxide and regeneration
of catalyst. The epoxide undergoes further oxidation to form
benzaldehyde and formaldehyde.
2
,4ꢀdiꢀtertꢀbutylphenol.It was interesting to observe that the
epoxidation reaction of cyclooctene was completely quenched
while the reaction of styrene proceeds smoothly thereby
convincingly suggesting a radical pathway for epoxidation of
2
4
cyclooctene and a concerted pathway for styrene.
This journal is © The Royal Society of Chemistry 2012
J. Name., 2012, 00, 1-3 | 9

Dalton Transactions
Page 10 of 14
View Article Online
ARTICLE
4DT03728F
DOI: 10.1039Jo/Curnal Name
ꢀ
1
Conclusion
spectrophotometer. Infrared spectra (400–4000 cm ) were
recorded from KBr pellets on Nicolet Magna IR 750 seriesꢀII
Two compartmental ligands H2L and H2L were inꢀsitu FTIR spectrophotometers. TOFꢀMS spectra were generated on
generated during the syntheses of three new trinuclear a waters HRMS instrument (model: XEVO G2QTOF).
1
2
+
complexes: (i) a heteroꢀtrinuclear complex (
5
) from a
[Cu(2,2'ꢀ
1
II
mononuclear
complex
[L Ni ]
and
2
II
bpy)(H O) ](NO ) , (ii) a homoꢀtrinuclear complex (L Cu ) Single crystal Xꢀray diffraction
2
2
3 2
3
2
(6) from the reaction between H L and a mixture of Cu(ClO )
2 4 2
and
Cu(NO3)2
in
1:1:2
mole
ratio
and
(iii) Single crystal Xꢀray data of complexes 5ꢀ7 were collected on a
2
+
[
[
[
Cu (L )(NCS) (NO )] that coꢀcrystallizes in
Cu (L ) Na (NO ) (NCS) ] unit to give complex
Cu (L ) Na (NO ) (NCS) ][Cu (L )(NCS) (NO )] (NO ) .5H
2
7 with an Bruker SMART APEXꢀII CCD diffractometer using graphite
3
2
3
2
7
monochromated Mo K radiation (λ= 0.71073 Å). Data
6
2
2
3 6
4
α
2
2
collection, reduction, structure solution, and refinement were
6
2
2
3 6
4
3
2
3
2
3 2
2
O obtained from H2L using [Cu(bipy)(H O) ](NO ) and performed using the Bruker APEXꢀII suite (v2.0ꢀ2) program.
2
2
3 2
NaSCN. The trinuclear Cu(II)ꢀNi(II)ꢀCu(II) complex, All available reflections to 2θmax were harvested and corrected
,contains a diamagnetic square planar Ni(II) metal ion that for Lorentz and polarization factors with Bruker SAINT plus.
bridges and prevents the two terminal Cu(II) centers to interact Reflections were then corrected for absorption; inter frame
5
2
8
magnetically. Therefore, this complex displays
paramagnetism. On the other hand, the three = ½ Cu(II) spin structures were solved by the direct methods and refined by
carriers in are ferromagnetically coupled (
leading to an ST = 3/2 ground state for this complex. A Similar SHELXꢀ97 software package. All the hydrogen atoms were
magnetic behavior is observed for complex with an average refined with anisotropic thermal parameters. Hydrogen atoms
Cu(II)ꢀCu(II) magnetic interaction of +1.6(3) K. The catalytic belonging to carbon and nitrogen atoms were placed in their
epoxidation of styrene and cyclooctene by ꢀBuOOH has been geometrically idealized positions, while hydrogen atoms on
explored in presence of a catalytic amount of complexes oxygen atoms of coordinated water were found on the
and in MeCN. As far as we know, these complexes exhibit difference Fourier map, and all of them were constrained to ride
a Curie scaling, and other systematic errors with SADABS. The
S
2
6
J/kB = +1.4(1) K) means of full matrix leastꢀsquare technique based on F with
2
9
7
t
5, 6
7
the highest TONs for epoxidation of olefins particularly in on their parent atoms. Hydrogen atoms were assigned to ideal
homogeneous liquid phase partial oxidation catalyzed by positions using the appropriate HFIX command in SHELXLꢀ
polynuclear Cu(II)ꢀSchiff base complexes. The concerted path 97. It is to be noted that the asymmetric unit of
7 contains two
was found to be operative for styrene oxidation while a radical bipyridine molecules and they were not stable enough during
path for the oxidation of cyclooctene.
refinement cycles, and thus all the positional parameters were
fixed in space to make them reasonable. One of the bipy
molecules is disordered over two positions along with a water
molecule (O21) residing at an inversion center.Thus for a
particular situation, in one set present in a unit cell, awater and
a bipy molecule were present on either side of the inversion
2ꢀ centre and they are engaged in hydrogen bonding. Furthermore,
Experimental
Reagents
3
,5ꢀdimethylpyrazole,
[Cu(2,2'ꢀbpy)(H O) ](NO ) ,
2 2 3 2
chloromethylꢀ6ꢀcarbaldehydeꢀ4ꢀmethylphenol and 2ꢀ[N,N
ꢀ
during the development of the structure it became apparent that
Ueq values of some atoms of both the bipyridyl ligand in were
larger than usual and thus ADP restraints were also applied in
Cu(NO ) ·3H O (Aldrich), order to make them acceptable. Furthermore, ADP restraints
bis(2ꢀmethylpyridyl)ꢀaminomethyl]ꢀ6ꢀcarbaldehydeꢀ4ꢀ
methylphenol were prepared using reported methods.
Cu(ClO ) ·6H O (Aldrich),
7
1
5,26,27
4
2
2
3 2
2
Ni(ClO ) ·6H O (Aldrich), ethylenediamine (Merck, India), were applied on oxygen atoms of a coordinated nitrate ion to
4
2
2
triethylamine (Et N) (Merck, India), bisꢀpicolylamine make them reasonable.Drawings of molecules were generated
3
(
Aldrich), sodium thiocyanate (Merck, India), 2,4ꢀdiꢀtert
butylphenol(Aldrich),acetylacetone (Merck, India), ammonium PLATON. The crystallographic data for 5ꢀ7 are given in Table
acetate (Merck, India), ꢀBuOOH (Aldrich)are of reagent grade
and used as received. Solvents like MeCN (Merck
ꢀ
with the programs like DIAMONDꢀ3.0, MERCURYꢀ3.0 and
t
4.
India),methanol, ethanol, THF and other solvents are of reagent Magnetic measurements
grade and were dried by standard methods before use.
The magnetic susceptibility measurements were obtained using
Physical measurements
a Quantum Design SQUID magnetometer MPMSꢀXL. This
magnetometer works between 1.85 and 300 K for dc applied
Elemental analyses were carried out using a Perkin–Elmer 240 fields ranging from ꢀ7 to 7 T. Measurements were performed on
1
elemental analyzer. H NMR were recorded in CDCl on a microcrystalline samples of 25.47 mg for
5
, 27.00 mg for
6 and
3
Bruker
300
MHz
NMR
spectrophotometer
using 24.29 mg for
7. The magnetic data were corrected for the
tetramethylsilane (δ = 0) as an internal standard. Electronic sample holder and the diamagnetic contributions.
spectra were recorded on Agilentꢀ8453 diode array UV–Vis
1
0 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 2012

Page 11 of 14
Journal Name
Dalton Transactions
View Article Online
ARTICLE
DOI: 10.1039/C4DT03728F
Experimental set up for catalytic oxidation
2ꢀchloromethylꢀ6ꢀcarbaldehydeꢀ4ꢀmethylphenol (1.515 g, 8.2
mmol) was dissolved in 15 ml dry THF in a round bottom flask.
The catalytic epoxidation reactions were carried out in the 3,5ꢀdimethylpyrazole (0.7883 g, 8.2 mmol) and triethylamine
liquid phase in a batch reactor at the desired temperature. (Et N) (1.659 g, 16.4 mmol) were dissolved in 10 ml dry THF
3
Typically, a 50 mL twoꢀneck roundꢀbottomed flask equipped and this mixture was added dropwise to the 2ꢀchloromethylꢀ6ꢀ
with a water condenser containing 50 mmol alkene in 10 mL carbaldehydeꢀ4ꢀmethylphenol solution. A rapid precipitation of
acetonitrile (MeCN) solvent and 0.05 mmol of catalyst was Et NHCl was observed and the colour of the solution turned
3
kept in a preꢀheated oil bath. 2 ml of tꢀBuOOH was then added bright yellow (Scheme 5). After 24 hours of stirring, the
to the mixture and was magnetically stirred continuously for 24 precipitate was filtered and subsequently solvent (THF) was
h. 0.5 mL of H O was added intermittently at a time interval of removed under reduced pressure to get an oily product that
2
2
6
0 min. The products of the epoxidation reactions were yielded a yellow crystalline solid after 2 days at 4°C. The solid
collected at different time intervals and were identified and product was then filtered and washed with cold ether. Yield
1
quantified by gas chromatography.
72%. H NMR (in CDCl , 300 MHz): δ in ppm 2.23ꢀ2.28 (9 H,
3
m, ꢀArCH ), 5.27 (2H, s, ꢀCH ), 7.09 (1H, s, ꢀArH), 7.27 (1H, s,
3
2
Table 4 Crystallographic data, details of data collection and ꢀArH), 7.28 (1H, s, ꢀArH), 9.88 (1H, s, ꢀCHO), 11.23 (1H, brs, ꢀ
structure refinement parameters for 5ꢀ7
ArOH).
Complex
7
5
6
C
3 10 16
N O
214
H
210 Cu12 N
56
Formula
C
50
H
50Cl
2
Cu
2
NiN12
O
16
C
44
H
44Cl
2
Cu
1230.44
Monoclinic
2 43 8
Na O S
Formula
Weight
Crystal
System
1
331.71
5302.32
Triclinic
Monoclinic
Scheme 5
Space group
P2/n (No. 13)
C2/c
(No. 15)
Pꢀ1(No. 2)
12.2539(8)
a [Å]
b [Å]
c [Å]
α [°]
β [°]
γ [°]
14.7716(2)
9.4644(1)
19.5306(2)
90
26.9977(19)
Synthesis of 2ꢀ(N,N
ꢀ
bis(2ꢀmethylpyridyl)aminoꢀmethyl)ꢀ6ꢀ
carbaldehydeꢀ4ꢀmethylphenol
12.3081(8)
15.3946(10)
90
18.6210(13)
27.0991(18)
102.507(4)
93.336(4)
108.678(4)
5664.2(7)
1
2
ꢀchloromethylꢀ6ꢀcarbaldehydeꢀ4ꢀmethylphenol (1.515 g, 8.2
mmol) was dissolved in 15 ml dry THF in a round bottom flask.
Bisꢀpicolylamine (1.630 g, 8.2 mmol) and triethylamine (Et N)
1.659 g, 16.4 mmol) were dissolved in 10 ml dry THF and this
97.530(1)
90
95.984(5)
90
3
3
V [Å ]
2706.92(5)
2
5087.6(6)
4
(
Z
mixture was added drop wise to the 2ꢀchloromethylꢀ6ꢀ
carbaldehydeꢀ4ꢀmethylphenol solution. An instant precipitation
D(calc)
1
1
.634
.304
1.606
1.554
3
[
g/cm ]
ꢀ
(MoK
/mm]
F(000)
Temperature
K)
θ MinꢀMax
º]
α
)
of Et NHCl was observed and the colour of the solution turned
3
1.427
2508
273
1.266
2711
100
[
to bright yellow (Scheme 6). After 24 hours of stirring, the
precipitate was filtered off. Solvent (THF) was removed under
reduced pressure to afford an oily product that yields a light
yellow crystalline solid after 2 days at 4°C. The solid product
1364
93
2
(
1
1
.6, 27.5
1.5, 26.7
1.3, 24.6
was then filtered and washed with cold ether. Yield 78%. H
[
NMR (in CDCl , 300 MHz): δ in ppm 2.27 (3H, s, ꢀMe); 3.85
3
ꢀ
19: 18 ; ꢀ12: 12 ; ꢀ25: ꢀ34: 34 ; ꢀ15: 15 ; ꢀ ꢀ14: 14 ; ꢀ21: 21 ; ꢀ
Dataset
(2H, s, ArꢀCH ꢀN); 3.94 (4H, s, NꢀCH ꢀpy); 7.16ꢀ7.68 (10H,
2
2
2
5
19: 19
36446, 5392,
0.107
31: 31
aromatic H); 8.57 (s, 1H, ꢀCHO); 10.39 (s, 1H, ꢀOH).
Tot., Uniq.
Data, R(int)
Observed
data [I > 2.0
σ(Ι)]
4
0002, 6241, 0.046
46084, 19066, 0.068
4547
2075
10719
Nref, Npar
6241, 371
5392, 340
19066, 1418
0
.0575, 0.1947,
.99
R, wR
2
, S 0.0515, 0.1668, 0.99
0.0848, 0.2330, 1.04
0
Scheme 6
Synthesis of 2ꢀformylꢀ4ꢀmethylꢀ6ꢀ(3,5ꢀdimethylꢀpyrazole)ꢀ
phenol
1
Synthesis of [Cu Ni(L )(2,2'ꢀbpy) (NO ) ].(ClO ) (5).
2
2
3 2
4 2
This journal is © The Royal Society of Chemistry 2012
J. Name., 2012, 00, 1-3 | 11

Dalton Transactions
Page 12 of 14
View Article Online
ARTICLE
4DT03728F
DOI: 10.1039Jo/Curnal Name
Synthesis of
2
2
2
1
ꢀformylꢀ4ꢀmethylꢀ6ꢀ(3,5ꢀdimethylpyrazole)phenol (0.244 g, [Cu (L ) Na (NO ) (NCS) ][Cu (L )(NCS) (NO )] (NO ) .
6
2
2
3 6
4
3
2
3
2
3 2
.00 mmol) and ethylenediamine (0.03 g, 0.50 mmol) were 5H O (7).
2
refluxed together in 30 ml of methanol for 40 minutes (Scheme
). After cooling to room temperature, nickel perchlorate 2ꢀ[N,Nꢀbis(2ꢀmethylpyridyl)aminomethyl]ꢀ6ꢀcarbaldehydeꢀ4ꢀ
7
hexahydrate (0.183 g, 0.50 mmol) was added and refluxed for 1 methylphenol (0.347g, 1.00 mmol) and ethylenediamine (0.03
h. [Cu(2,2'ꢀbpy)(H O) ](NO ) (0.3795 g, 1 mmol) was then g, 0.50 mmol) were refluxed together in 30 ml methanol for 40
2
2
3 2
added and reflux was continued for another 1 h. The yellow minutes. After cooling to room temperature [Cu(2,2'ꢀ
solution turned into brownishꢀgreen. It was filtered and kept bpy)(H O) ](NO ) (0.569 g, 1.5 mmol) and sodium
2
2
3 2
aside. Slow evaporation of methanol gives rod shaped brownish thiocyanate (0.098 g, 1.2 mmol) were added and reflux was
green crystals suitable for Xꢀray studies. Anal.Calc. continued for another 1 h. The yellow solution turned into
ForC H Cl Cu NiN O (M.W. 1331.71): C, 45.10%; H, green. It was filtered and kept aside undisturbed. Slow
5
0
50
2
2
12 16
3
.78%; N, 12.62%. Found: C, 45.45%; H, 3.58%; N, 12.35%. evaporation of methanol gives rod shaped brownish green
ꢀ
1
ꢀ
IR: ν/cm : 1081 (ClO , counter anion), 1643 (C=N), 1383 (
ꢁ
ꢀ
crystals
suitable
for
Xꢀray
studies.Anal.Calc.
4
NO ) (Fig. S6).
ForC214H210Cu N Na O S (M.W.5305.95): C, 48.31%; H,
3
12 56
2
43 8
3
1
2
.97%; N, 14.74%. Found: C, 47.70%; H, 3.85%; N,
ꢀ
1
4.98%.IR: ν/cm : 3449 (water, free solvent), 1632 (C=N),
084 ( ꢀNCS), 1382 ( ꢀNO ) (Fig. S8).
ꢁ
ꢁ
3
Acknowledgements
Financial support from CSIR (Ref.02(2490)/11/EMR ꢀII) and UGC
[39ꢀ735/2010(SR)] New Delhi, are gratefully acknowledged.R.C.,
M.R. and I.B. thank the Erasmus Mundus Mobility with Asia
program for the Ph.D. fellowship of I. B, the University of
Bordeaux, the CNRS, and the Region Aquitaine for financial
support.
Scheme 7
2
Synthesis of [Cu (L )(NO ) ].(ClO ) (6)
3
3 2
4 2
Notes and references
A
mixture of 2ꢀ[N,Nꢀbis(2ꢀmethylpyridyl)aminomethyl]ꢀ6ꢀ
a
Department of Chemistry Jadavpur University, Kolkata700 032,
carbaldehydeꢀ4ꢀmethylphenol (0.347 g, 1.00 mmol) and
ethylenediamine (0.03 g, 0.50 mmol) were refluxed in 30 ml of
methanol for 40 minutes (Scheme 8). After cooling to room
temperature copper perchlorate hexahydrate (0.185 g, 0.50
mmol) was added and refluxed for 1 h. Copper nitrate Postgraduate Department of Chemistry, Panskura Banamali
trihydrate (0.242 g, 1 mmol) was then added and reflux was College, Panskura RS, PurbaMedinipur, West Bengal 721
continued for another 1 h. The yellow solution turned into 152, India.
India; Fax: 91ꢀ33ꢀ2414ꢀ6223. Eꢀmail: mali@chemistry.jdvu.ac.in
b
CNRS, CRPP, UPR 8641, Fꢀ33600 Pessac, France
;
c
Univ. Bordeaux, CRPP, UPR 8641, Fꢀ33600 Pessac, France.
d
green. It was filtered and kept aside. Slow evaporation of
†
Electronic
Supplementary
Information
(ESI)
available:
methanol gives rod shaped green crystals suitable for Xꢀray
studies. Anal.Calc. ForC H Cl Cu N O (M.W. 1230.44): C,
Crystallographic data in CIF format (CCDC no. 972141 (5), 972142
(6),972143 (7), table of bond distances and angles, are deposited in
4
4
44
2
3
10 16
4
2.95%; H, 3.60%; N, 11.38%. Found: C, 42.35%; H, 3.98%;
ESI
.
ꢀ
1
ꢀ
N, 11.60%. IR: ν/cm : 1079 (ClO , counter anion), 1604
4
(
C=N), 1385(ꢁꢀNO ) (Fig. S7).
3
References
1
(a) L. M. Mirica, M. Vance, D. J. Rudd, B. Hedman, K. O. Hodgson,
E. I. Solomon and T. D. P. Stack, Science,2005, 308, 1890ꢀ1892; (b)
Y. Lu, N.Yeung, N. Sieracki and N. M. Marshall, Nature,2009, 460
,
8
3
55ꢀ862; (c) L. Que Jr. and W. B. Tolman, Nature,2008, 455, 333ꢀ
40; (d) Y. Suh, M. S. Seo, K. M. Kim, Y. S. Kim, H. G. Jang, T.
Tosha, T. Kitagawa, J.Kim and W. J. Nam, Inorg. Biochem.,2006,
00, 627ꢀ633; (e) Nam, W. Acc. Chem. Res.,2007, 40, 522ꢀ531; (f ) J.
1
Cho, R. Sarangi and W. Nam, Acc. Chem. Res.,2012, 45, 1321ꢀ1330.
E. I. Solomon, U. M. Sundaram andT. E. Machonkin, Chem.
Rev.,1996, 96, 2563ꢀ2606.
Scheme 8
2
1
2 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 2012

Page 13 of 14
Journal Name
Dalton Transactions
View Article Online
ARTICLE
DOI: 10.1039/C4DT03728F
3
(a) C. D. Nicola, F. Garau, Y. Y. Karabach, L. M. D. R. S.Martins,
M. Monari, L. Pandolfo, C. Pettinari and A. J. L. Pombeiro, Eur. J.
Inorg. Chem., 2009, 666ꢀ676; (b) V. Mahadevan, R. Gebbink and T.
7
(a) J. O. Lundberg, E. Weitzberg and M. T. Gladwin, Nat. Rev.
Drug.Discov., 2008, , 156ꢀ167; (b) E. Weitzberg and J. O.
Lundberg, Nitric Oxide,1998, , 1ꢀ7; (c) J. O. Lundberg, E.
Weitzberg, J. A. Cole and N. Benjamin, Nat. Rev. Microbiol., 2004,
, 593ꢀ602; (d) J. O. Lundberg and E. Weitzberg, Arterioscler.
7
2
D. P. Stack, Curr. Opin. Chem. Biol.,2000, 4, 228ꢀ234; (c) A. P. Cole,
D. E. Root, P. Mukherjee, E. I. Solomon and T. D. P. Stack,
2
Science,1996, 273, 1848ꢀ1850; (d) W. B. Tolman and E. A. Lewis,
Thromb. Vasc. Biol.,2005, 25, 915ꢀ922; (e) M. T. Gladwin, A. N.
Chem. Rev
Kopylovich, M. V. Kirillova, M. Haukka, M. F. C. G. da Silva and A.
J. L. Pombeiro, Angew. Chem., Int. Ed 2005, 44, 4345; (f) M. V.
Kirillova, A. M.Kirillov, M. F. C.G. da Silva andA. J. L. Pombeiro,
Eur. J. Inorg. Chem 2008, 3423ꢀ3427; (g) P. P. Y. Chen, R. B.ꢀ
.
,
2004, 104, 1047ꢀ1076; (e) A. M. Kirillov, M. N.
Schechter, D. B. KimꢀShapiro, R. P. Patel, N. Hogg and S. Shiva,
Nat. Chem. Biol.,2005, 1, 308ꢀ314; (e) J. L. Zweier, A. Samouilov
.,
and P. Kuppusamy, Biochim. Biophys.Acta,1999, 1411, 250ꢀ262.
J. B. Fontecha, S. Goetz and V. McKee, Angew. Chem., Int. Ed.,2002,
41, 4553ꢀ4556.
8
9
.
,
G.Yang, J. C.ꢀM. Lee and S. I. Chan, Proc. Natl. Acad. Sci. U. S.
A.,2007, 104, 14570ꢀ14575; (h) R. A.Himes and K. D. Karlin, Curr.
Opin. Chem. Biol.,2009, 13, 119ꢀ131.
P. GomezꢀSaiz, J. GarcıaꢀTojal, V. D. Gomez, R. G. Garcıa, J. L.
Pizarro, M. I. Arriortua and T. Rojo, Inorg. Chem. Commun.,2005, 8,
259ꢀ262.
4
(a) S. Itohin Comprehensive Coordination Chemistry, Vol. 8 (Eds.: J. 10 (
a
) J. L. Sessler, E. Tomat, T. D. Mody, V. M. Lynch, J. M. Veauthier,
U. Mirsaidov and J. T. Markert, Inorg. Chem., 2005, 44, 2125ꢀ2127;
) J. Pons, F. J. Sanchez, J. Casabo, A. AlvarezꢀLarena and J. F.
Piniella Ros, J. Inorg. Chem. Commun., 2003, , 833ꢀ836.
McCleverty, T. J. Meyer, L. Que, W. B. Tolman), 2nd ed., Elsevier, 11 K. Sakai, Y. Yamada, T. Tsubomura, M. Yabuki, M. Yamaguchi,
nd
A. McCleverty, T. J. Meyer, L. Que,W. B. Tolman), 2 ed., Elsevier,
Dordrecht, 2003
,
chap. 8.15, 369ꢀ393; (b) D. H. Lee in
Vol. (Eds.: J. A.
(b
Comprehensive Coordination Chemistry
,
8
6
Dordrecht, 2003, chap. 8.17, 437ꢀ457; (c) J. J. R. Frafflsto da Silva
and R. J. P. Williams, The Biological Chemistry of the Elements
Oxford University Press, Oxford, 2001 (d) J. P. Klinman, Chem.
Inorg. Chem.,1996, 35, 542ꢀ544.
,
12 P. K.Nanda, G. Aromí and D. Ray, Inorg. Chem.,2006, 45, 3143ꢀ
;
3145.
Rev.,1996, 96, 2541ꢀ2561; (e) M. Ayala and E. Torres, Appl. Catal. 13 (
A,2004, 272, 1ꢀ13; (f) S. J. Elliot, M. Zhu, L. Tso, H.ꢀH. T. Nguyen,
J. H.ꢀK. YipandS. I. Chan, J. Am. Chem. Soc.,1997, 119, 9949ꢀ9955;
a
) D. R. Armstrong, W. Clegg, A. M. Drummond, S. T. Liddle and R.
E. Mulvey, J. Am. Chem. Soc.,2000, 122, 11117ꢀ11124; ( ) E. C.
Constable, C. E. Housecroft, B. M. Kariuki, N. Kelly and C. B.
Smith, Chem.Commun.,2001, 2134ꢀ2135; ( ) G. Aromí, A. R. Bell,
M. Helliwell, J. Raftery, S. J. Teat, G. A.Timco, O. Roubeau and R.
E. P. Winpenny, Chem. Eur. J.,2003, , 3024ꢀ3032; ( ) L. Y. Wang,
b
(g) R. L.Lieberman and A. C. Rosenzweig, Crit. Rev. Biochem. Mol.
c
Biol.,2004, 39, 147ꢀ164; (h) R. L.Lieberman and A. C. Rosenzweig,
Nature, 2005, 434, 177ꢀ182; (i) K. C. Gupta and A. K. Sutar,Coord.
Chem. Rev.,2008, 252, 1420–1450; (j) S. M. Islam, A. Singha Roy, P.
Mondal, M. Mubarak, S. Mondal, D. Hossain, S. Banerjee and S. C.
9
d
S. Igarashi, Y. Yukawa, Y. Hoshino, O. Roubeau, G. Aromí and R. E.
P. Winpenny, Dalton Trans.,2003, 2318ꢀ2324.
Santra ,J. Mol. Cat. A: Chem., 2011, 336, 106ꢀ114; (k) C.Adhikary, 14 S. Biswas
R.Bera, B. Dutta, S. Jana, G. Bocelli, A. Cantoni, S. Chaudhuri and Dalton Trans., 2013, 42, 13210ꢀ13219.
S.Koner, Polyhedron,2008, 27 1556ꢀ1562; (l) D. Saha, T. Maity, T. 15 S. Biswas, A. Dutta, M. Dolai, I. Bhowmick, M. Rouzières, H. M.
Dey, S. Koner, Polyhedron, 2012, 35, 55ꢀ61. Lee, R. Clérac and M. Ali, Eur. J. Inorg. Chem.,2013 4922ꢀ4930.
(a) P. Gamez, P. G. Aubel, W. L.Driessen and J .Reedijk, Chem. Soc. 16 D. Mandal, M. Chauhan, F. Arjmand, G. Aromí and D. Ray, Dalton
,
A. Dutta, M. Debnath, M. Dolai, K. K.Das and M. Ali,
,
,
5
Rev.,2001, 30, 376ꢀ385; (b) K. D. Karlin and A. D. Z. Phlerin
Trans.,2009, 9183ꢀ9191.
nd
Bioinorganic Catalysis (Eds.: J. Reedijk, E. Bouwman), 2 ed., 17 K. D. Karlin and Z. Tyeklor, (Eds.), Bioorganic Chemistry of Copper
,
Dekker, New York, 1999, 469–534; (c) M. C. Mimmi, M. Gullotti, L.
Chapman & Hall, New York, 1993.
Santagostini, G. Battaini, E. Monzani, R. Pagliarin, G. Zoppellaro and 18Y. Y. Karabach, A. M. Kirillov, M. F. C. G. D. da Silva, M. N.
L. Casella, Dalton Trans., 2004, 2192ꢀ2201; d) L. M. Mirica, X.
E.Ottenwaelder and T. D. P. Stack, Chem. Rev.,2004, 104, 1013ꢀ
Kopylovich and A. J. L. Pombeiro, Cryst. Growth Des.,2006, 6,
2200ꢀ2203.
1
1
045; (e) E. A. Lewis and W. B. Tolman, Chem. Rev.,2004, 104
,
19 (
a
) S. Mukherjee, T. Weyhermuller, E. Bothe, K. Wieghardt and P.
) C. P.Pradeep,
047ꢀ1076.
Chaudhuri, Eur. J. Inorg. Chem.,2003, 863ꢀ875; (
b
6
(a) G. B. Shulpin, J. Gradinaru and Y. N. Kozlov, Org. Biomol.
Chem., 2003, , 3611ꢀ3617; (b) R. S.da Cruz, J. M. D. E.Silva,
S.Supriya, P. S.Zacharias and S. K. Das, Polyhedron,2006, 25, 3588ꢀ
1
3592.
U.Arnold, M. S.Sercheli and U. J. Schuchardt, Braz. Chem. 20 S. Biswas, A. Dutta, M. Dolai and M. Ali, communicated to
Soc.,2002, 13, 170ꢀ176; (c) T.Ohta, T. Tachiyama, K. Yoshizawa, T. Polyhedron.
Yamabe, T. Uchida and T. Kitagawa, Inorg. Chem.,2000, 39, 4358ꢀ 21 (a) M. Ali, I. Zilbermann, H. Cohen, A. I. Shames and D. Meyerstein,
4
369; (d) S. Velusamy and T. Punniyamurthy, Tetrahedron
Inorg. Chem. 1996, 35, 5127-5131; (b) T. Nash, Nature, 1952, 170,
Lett.,2003, 44, 8955ꢀ8957; (e) U. Schuchardt, R. Pereira and M. Rufo,
976.
J. Mol. Catal. A, 1998, 135, 257ꢀ262; (f) R. Raja and P. Ratnasamy, 22 P. Roy, K. Dhara, M. Manassero and P. Banerjee, Inorg. Chem.
Catal. Lett.,1997, 48, 1ꢀ10; (g) D.H.R. Barton, S. D. Beviere, W. Comm., 2008,11 265ꢀ269.
Chavasiri, E. Csuhai and D. Doller,Tetrahedron,1992, 48, 2895ꢀ2910; 23 P. Roy, M. Nandi, M. Manassero, M. Riccó, M. Mazzani, A.
,
(
h) T. Okuno, S. Ohba and Y. Nishida, Polyhedron,1997, 16, 3765ꢀ
774; (i) N. Komiya, T.Naota, Y. Oda and S. I. J Murahashi, Mol.
Catal. A.,1997, 117, 21ꢀ35.
Bhaumik and P. Banerjee, Dalton Trans., 2009, 9543ꢀ9554.
(a) J. Zhang, A. V. Biradar, S. Pramanik, T. J. Emge, T. Asefa and J.
2
4
3
.
This journal is © The Royal Society of Chemistry 2012
J. Name., 2012, 00, 1-3 | 13

Dalton Transactions
Page 14 of 14
View Article Online
ARTICLE
4DT03728F
DOI: 10.1039Jo/Curnal Name
Li, Chem. Commun., 2012, 48, 6541ꢀ6543; (b) M. Yonemitsu, Y.
Tanaka and M. Iwamoto, J. Catal., 1998, 178, 207ꢀ213; (c) R. D.
Oldroyd, J. M. Thomas, T. Maschmeyer, P. A. MacFaul, D. W.
Snelgrove, K. U. Ingold and D. D. M. Wayner, Angew. Chem., Int.
Ed. Engl., 1996, 35, 2787ꢀ2790; (d) J. Sebastian, K. M. Jinka and R.
V. Jasra, J. Catal., 2006, 244, 208ꢀ218.
2
2
6 E. Lambert, B. Chabut, S. C. Noblat, A. Deronzier, G. Chottard, A.
Bousseksou, J. P. Tuchagues, J. Laugier, M. Bardet and J. M. Latour,
J. Am. Chem. Soc., 1997, 119, 9424ꢀ9437.
7 E. Garribba, G. Micera, D. Sanna and L. StrinnaꢀErre, Inorg. Chim.
Acta, 2000, 299, 253ꢀ261.
2
5 (a) D. W. Snelgrove, J. Lusztyk, J. T. Banks, P. Mulder and K. U. 28 G. M. Sheldrick, SAINT (Version 6.02), SADABS (Version 2.03),
Ingold, J. Am. Chem. Soc., 2001, 123, 469ꢀ477. (b) P. A. MacFaul, I.
W. C. E. Arends, K. U. Ingold and D. D. M. Wayner, J. Chem. Soc.,
Perkin Trans 2,1997, 2, 135ꢀ145.
Bruker AXS Inc., Madison, Wisconsin, 2002
9 ( G. M. Sheldrick, Acta Crystallogr., Sect. A: Found.
Crystallogr.2007, 64, 112ꢀ122; ( ) G. M. Sheldrick, SHELXLꢀ97,
Crystal Structure Refinement Programme, University of
Göttingen1997
.
2
a)
b
.
_
____________________________________________________________________________________________________
1
4 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 2012