H. Kim et al. / Inorganica Chimica Acta 387 (2012) 346–351
347
product was collected by filtration, washed with methanol, and
dried in air. The crude product contains relatively small amount
(<20%) of an orange solid {cis-[Ni(H2L2)](ClO4)2}. The solubility of
trans-[Ni(H2L2)](ClO4)2 in acetonitrile–water (3:1) was found to
be considerably higher than that of cis-[Ni(H2L2)](ClO4)2. The pure
product was isolated by fractional recrystallizations of the crude
product in acetonitrile–water (3:1). Yield: ꢁ60%. Anal. Calc. for
NR
NH
HN
RN
NH
NR
RN
HN
C
36H52Cl2N4NiO10 (Mw: 830.42): C, 52.07; H, 6.31; N, 6.75. Found:
C, 51.74; H, 6.16; N, 6.48%. FAB mass (m/z): 729.4 for [Ni(H2L2)
+ClO4]+, 629.5 for [Ni(HL2)]+. IR (cmꢂ1): 3223 (mN
L1: R = H
L2: R = X
L3: R = CH2CH2OH
L4: R = CH2CONH2
L6: R = Y
H
C@O
A ), 1631 (
): 2.90
m
),
, ClO ꢂ). Magnetic moment (
at 20 °C.
ClAO
1100 (m
4
eff
l
B
l
2.5. Preparation of cis-[Ni (H2L2)](ClO4)2
To a boiling methanol solution (30 ml) of Ni(OAc)2ꢀ4H2O (ca.
2.0 g) was added H2L2 (0.5 g). The mixture was refluxed for 1 h
and then cooled to room temperature. After the addition of HClO4
(2.0 ml) and water (10 ml), the resulting solution was allowed to
stand at room temperature to produce an orange solid. The product
was collected by filtration, washed with methanol, and dried in air.
The crude product also contains relatively small amount (<20%) of
a pale yellow solid {trans-[Ni(H2L2)](ClO4)2}. The pure product was
isolated by the fractional recrystallizations of the crude product in
acetonitrile–water (3:1). Yield: ꢁ60%. Anal. Calc. for C36H52Cl2
N4NiO10 (Mw: 830.42): C, 52.07; H, 6.31; N, 6.75. Found: C,
52.28; H, 6.26; N, 6.74%. FAB mass (m/z): 729.4 for [Ni(H2L2)
+ClO4]+, 629.5 for [Ni(HL2)]+. IR (cmꢂ1): 3217 (mN
L5: R = CH2CH2COOMe
O
C
O
X = CH2
C
Y =
Molar susceptibilities were corrected for diamagnetism of the
ligand and/or the anions by use of Pascal’s constants. Elemental
analyses were performed at the Research Center for Instrumental
Analysis, Daegu University, Gyeongsan, Korea. FAB-mass spectra
were performed at the Korea Basic Science Institute, Daegu, Korea.
H
NAH
A ), 3261 (
m
),
, ClO ꢂ). Magnetic moment
C@O
C@O
ClAO
4
1660 (
m
), 1640 (
B
m
), 1100 (m
eff
(l
): 2.92
l
at 20 °C.
2.2. Preparation of H2L2
2.6. Preparation of trans-[NiL2]
The macrocycle L1 was prepared by the reported procedure [17].
A chloroform solution (30 ml) of L1 (2.0 g, 6.0 mmol) and phenacyl
bromide (3.5 g, 17.6 mmol) was refluxed for ca. 30 h and then
stored in a refrigerator until a white precipitate formed. The solid
collected by filtration was dissolved in acetonitrile (20 ml). After
the addition of 1.0 M NaOH aqueous solution (20 ml), the mixture
was evaporated at room temperature to precipitate a white solid. It
was collected by filtration and was recrystallized from warm chlo-
roform–methanol (3:1) solution. Yield: ꢁ70%. Anal. Calc. for
To an acetonitrile solution (20 ml) of trans-[Ni(H2L2)](ClO4)2
(0.5 g) was added 0.1 M NaOH aqueous solution (20 ml). The
resulting solution was evaporated at room temperature to precip-
itate a pale purple solid. The product was collected by filtration,
washed with water, and dried in air. It was recrystallized from
chloroform. Yield: ꢁ80%. Anal. Calc. for
629.5): C, 68.69; H, 8.01; N, 8.90. Found: C, 68.02; H, 7.83; N,
8.65%. FAB mass (m/z): 629.5 for [Ni(HL2)]+. IR (cmꢂ1): 3235 (
NAH).
Magnetic moment ( eff): 2.88 lB at 20 °C.
C36H50N4NiO2 (Mw:
m
l
C
36H52N4O2 (Mw: 572.8): C, 75.48; H, 9.15; N, 9.78. Found: C,
75.10; H, 8.82; N, 9.94%. GC–mass (m/z): 573 (M+). IR (cmꢂ1):
2.7. Preparation of cis-[Ni(HL2)]ClO4
3298(mNAH), 1637(m
C@O). 1H NMR (CDCl3): d 1.03 (d, Me), 7.2 (d,
C6H5), 7.3 (d, C6H5), 7.6 (d, C6H5). 13C NMR (CDCl3): 18.0, 21.5,
25.0, 25.6, 29.7, 34.2, 48.5, 50.8, 56.1, 77.5, 106.5, 125.2, 127.3,
127.7, 128.2, 128.9, 129.6, 138.3 (ACH2COC6H5) ppm.
To an acetonitrile solution (20 ml) of cis-[Ni(H2L2)](ClO4)2
(0.5 g) was added 0.1 M NaOH aqueous solution (20 ml). The
resulting solution was evaporated at room temperature to precip-
itate a pale orange solid. The product was collected by filtration,
washed with water, and dried in air. It was recrystallized from
2.3. Preparation of [H4L2](ClO4)2
methanol. Yield: ꢁ80%. Anal. Calc. for
C36H51ClN4NiO6 (Mw:
729.96): C, 59.23; H, 7.04; N, 7.68. Found: C, 59.03; H, 7.16; N,
To an acetonitrile suspension (20 ml) of H2L2 (1.0 g) was added
concentrated HClO4 (1.0 ml) dissolved in water (20 ml). The mix-
ture was stirred for 1 h at room temperature. The white solid,
which had been formed, was collected by filtration, washed with
7.26%. FAB mass (m/z): 729.6 for [Ni(H2L2)+ClO4]+, 629.7 for
[Ni(HL2)]+. IR (cmꢂ1): 3240 (
m
NAH), 3268 (
mNAH), 1660 (mC@O),
A , ClO ꢂ). Magnetic moment (
l
at 20 °C.
1100 (mCl
O
4
eff
): 2.85
B
l
water, and dried in air. Yield: ꢁ90%. Anal. Calc. for C36H54Cl2N4O10
:
C, 55.88; H, 7.03; N, 7.24. Found: C, 55.52; H, 6.95; N, 7.37%. FAB
2.8. Crystal structure determination
mass (m/z): 673.4 for [H4L2+ClO4]+, 573.5 for [H3L2]+. IR (cmꢂ1):
3230(mNAH), 1640 (mC@O), 1100 (m
ClAO, ClO4ꢂ).
Single crystals of trans-[Ni(H2L2)](ClO4)2ꢀ2DMSO and cis-
[Ni(H2L2)](ClO4)2ꢀH2O suitable for X-ray study were grown from
water–DMSO and water–acetonitrile solutions, respectively. Inten-
sity data were collected on a Rigaku R-AXIS RAPID II-S diffractom-
2.4. Preparation of trans-[Ni(H2L2)](ClO4)2
To a boiling methanol solution (30 ml) of H2L2 (0.5 g) was added
Ni(OAc)2ꢀ4H2O (ca. 2.0 g). The mixture was refluxed for 1 h and
then cooled to room temperature. After the addition of HClO4
(2.0 ml) and water (10 ml), the resulting solution was allowed to
stand at room temperature to produce a pale yellow solid. The
eter equipped with graphite monochromated MoKa (k = 0.71073
Å) radiation source and imaging plate detector (460 ꢃ 256 mm).
A total of 240 oscillation images were collected at 100 k using
widths of 3° in
x the raw data were processed to give structure
factors using the RAPID AUTO program. The structure was solved