1
44
J. Britton et al. / Journal of Molecular Structure 1047 (2013) 143–148
(
0.11 g, 2.02 mmol) and ammonia gas was bubbled through the
OH
CN
DMSO, K CO ,
solution under stirring at room temperature for several hours until
the solution took on a pale green color. After removing the solvent,
the residue was dissolved in toluene and washed several times
with water.
CN
2
3
NH3, CH ONa
3
O2N
O
Yield 0.47 g (80%) 1H NMR (THF-d
8
): d = 8.62 (3H, s, NH), 7.99
(
2H, d, ArAH), 7.33 (2H, d, ArAH), 7.14 (1H, s, ArAH), 7.06 (1H, d,
(3)
(4)
(5)
ꢁ1
ArAH), 6.80 (1H, d, ArAH). IR spectrum: 2949 cm
stretch), 1598 cm (C@C aromatic), 1533 cm (C@C aromatic),
1
(@CAH
ꢁ1
ꢁ1
ꢁ1
ꢁ1
ꢁ1
506 cm (C@C aromatic), 1435 cm (CH
3
bending), 1269 cm
ꢁ1
ꢁ1
(
CAOAC stretch), 1229 cm (CAOAC stretch), 1144 cm (CAOAC
ꢁ1
stretch), 1053 cm (CAOAC stretch).
N H2
N H
2.2.2. Synthesis of indium hemiporphyrazine (ClInHp, 6), Scheme 1
O
H2N
N H2
+
ClInHp was synthesized by combining 4-tert-butyl-phenoxyiso-
N H
indoline (5) (0.18 g, 0.63 mmol), InCl
3
(0.14 g, 0.63 mmol) and 1, 3,
(
2)
5
-triaminobenzene (2) (0.077 g, 0.63 mmol) in methanol and stir-
N H
(
5)
ring under reflux overnight. The product was then purified using
a silica column and THF, followed by THF:water 40:60 mixture
and finally EtOH as eluents, so as to separate all the components.
The final product in EtOH fraction was the compound of interest.
MeOH,
ClInHp: Yield: 0.16 g, 28%. UV–visible (DMF): kmax nm (log
e)
InCl
3
3
92.5 (3.29), 424.5 (3.18), 454 (2.99). NMR data listed in Table 1.
ꢁ1
ꢁ1
IR spectrum: 3300 cm (NAH stretch), 1711 cm (C@N groups),
1625 cm
ꢁ1
ꢁ1
ꢁ1
ꢁ1
NH2
(NAH bending), 1357 cm
(CAN aryl stretch), 1222 cm
(CAN aryl stretch),
ꢁ1
1
1
313 cm
021 cm
(aromatic ether),
(aliphatic amine). Mass Spectrum Calculated:
+
N
N
N
N
912.2 amu. Found: 913.1 amu [M+1] .
Cl
O
O
In
N
2
.2.3. Equipment
A convenient and fast experimental method to assess materials
N
for NLO (including optical limiting) is the open aperture Z-scan
experiment. This measures the total transmittance through the
sample as a function of incident laser intensity while the sample
is gradually moved through the focus of a lens (along the z-axis).
The Z-scan equipment employed in this work was fabricated at
the University of Stellenbosch in South Africa. All experiments de-
scribed in this study were performed using a tunable laser system
consisting of an Nd:YAG laser (355 nm, 135 mJ/4–6 ns, repetition
rate = 20 Hz) pumping an optical parametric oscillator (OPO,
NH2
(
6)
Scheme 1. Synthetic route for ClInHp (6).
enhance intersystem crossing to the triplet state and hence im-
prove NLO parameters. The NLO studies in this work were con-
ducted in DMF solutions.
3
3
0 mJ/3–5 ns) with a wavelength range of 420–2300 nm (NT-
42B, Ekspla).
UV–visible spectra were recorded on a Shimadzu UV-2550
2
. Experimental
.1. Materials
,5-Dinitroaniline (1), 4-nitrophthalonitrile (3), 4-tert-butyl-
spectrophotometer. Mass spectrometer used was a Bruker MAL-
DI-TOF/TOF Mass Spectrometer (Autoflex III), with the compound
placed in an a
-cyano-4-hydroxycinnamic acid matrix. 1H, C,
13
2
DEPT135 (DEPT = distortionless enhancement by polarization
transfer) and 2D NMR spectra (Heteronuclear Single Quantum
Coherence (HSQC), Heteronuclear Multiple Bond Correlation
(HMBC) and Nuclear Overhauser Enhancement Spectroscopy
(NOESY)) were obtained on a Bruker Avance AMX 600 MHz spec-
3
phenol (4), methanol (MeOH), ethanol (EtOH), palladium on acti-
vated carbon, celite, dimethylsulphoxide (DMSO), dimethylform-
amide (DMF), potassium carbonate, sodium methoxide, ammonia
gas, indium chloride and tetrahydrofuran (THF) were obtained
from Sigma–Aldrich. 1,3,5-Triaminobenzene (2) was synthesized
from complex 1, according to literature reports [10].
trometer using THF-d
8
as a solvent. Fluorescence measurements
were taken on a Varian Eclipse spectrofluorimeter. Infra-red spec-
tra were recorded on
Spectrometer.
a Perkin Elmer Spectrum 100 FT-IR
2
2
.2. Synthesis of In hemiporphyrazine (Hp)
2
.2.4. Third order parameters
Once the open aperture data was collected with the Z scan, it
.2.1. Synthesis of 4-tert-butyl-phenoxyisoindoline (5), Scheme 1
was analyzed by using the procedure described by Sheik-Bahae
et al. [11], using the following equation:
4
-Nitrophthalonitrile (3) (0.50 g, 2.89 mmol) and 4-tert-butyl-
phenol (4) (0.43 g, 2.89 mmol) were stirred overnight in DMSO in
the presence of excess potassium carbonate. The resulting com-
pound was purified using a silica gel column, the solvent removed
and then rinsed with water to remove any remaining potassium
carbonate and allowed to dry. The compound (0.56 g, 2.02 mmol)
was then placed in methanol, along with sodium methoxide
Z
1
1
s2
ꢁ
TðzÞ ¼ pffiffiffi
ln½1 þ q ðzÞe ꢂd
s
ð1Þ
(z)
0
p
q0ðzÞ ꢁ1
where T(Z) is the normalized transmittance of the sample and q
0
is given by the following equation: