Synthesis, structural characterization and theoretical studies of a new Schiff base 4-(((3-(tert-Butyl)-(1-phenyl)pyrazol-5-yl) imino)methyl)phenol

Article abstract of DOI:10.1016/j.molstruc.2017.09.078

4-(((3-(tert-Butyl)-(1-phenyl)pyrazol-5-yl)imino)methyl)phenol (4-OHFPz) was synthesized and characterized by FT-IR, MS, NMR, and single-crystal X-ray diffraction. Optimization of molecular geometry, vibrational frequencies, and chemical shifts were calculated by using the methods of density functional theory (DFT) with B3LYP and B3PW91 as functionals and Hartree-Fock with 6-311G++(d,p) as basis set using the GAUSSIAN 09 program package. With the VEDA 4 software, the vibrational frequencies were assigned in terms of the potential energy distribution (PED). The equilibrium geometries calculated by all methods were compared with X-ray diffraction results, indicating that the theoretical results matches well with the experimental ones. The data obtained from the vibrational analysis and the calculated NMR are consistent with the experimental spectra.

Full text of DOI:10.1016/j.molstruc.2017.09.078

Accepted Manuscript
Synthesis, structural characterization and theoretical studies of a new Schiff base 4-
(((3-(tert-Butyl)-(1-phenyl)pyrazol-5-yl) imino)methyl)phenol
Fernando Cuenú, Jennifer Londoño-Salazar, John Eduard Torres, Rodrigo Abonia,
Richard F. D'Vries
PII:
S0022-2860(17)31276-0
10.1016/j.molstruc.2017.09.078
MOLSTR 24327
DOI:
Reference:
To appear in: Journal of Molecular Structure
Received Date: 2 August 2017
Revised Date: 19 September 2017
Accepted Date: 21 September 2017
Please cite this article as: F. Cuenú, J. Londoño-Salazar, J.E. Torres, R. Abonia, R.F. D'Vries,
Synthesis, structural characterization and theoretical studies of a new Schiff base 4-(((3-(tert-Butyl)-
(1-phenyl)pyrazol-5-yl) imino)methyl)phenol, Journal of Molecular Structure (2017), doi: 10.1016/
j.molstruc.2017.09.078.
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Graphical abstract

ACCEPTED MANUSCRIPT
Synthesis, Structural Characterization and Theoretical Studies
of a new Schiff Base 4-(((3-(tert-Butyl)-(1-phenyl)pyrazol-5-yl)
imino)methyl)phenol
a*
a
a
Fernando Cuenú , Jennifer Londoño-Salazar , John Eduard Torres , Rodrigo
b
c
Abonia , Richard F. D’Vries
a
Laboratorio de Química Inorgánica y Catálisis, Programa de Química, Universidad del
Quindío, Carrera 15, Calle 12 Norte, Armenia, Colombia
b
Departamento de Química, Universidad del Valle, AA 25630, Cali-Colombia
c
Universidad Santiago de Cali, Calle 5 # 62-00, Cali, Colombia
*Corresponding author. Laboratorio de Química Inorgánica y Catálisis, Programa de Química,
Universidad del Quindío, Carrera 15, Calle 12 Norte, Armenia-Colombia. Mail:
fercuenu@uniquindio.edu.co
ABSTRACT
4
-(((3-(tert-Butyl)-(1-phenyl)pyrazol-5-yl)imino)methyl)phenol
(4-OHFPz)
was
synthesized and characterized by FT-IR, MS, NMR, and single-crystal X-ray diffraction.
Optimization of molecular geometry, vibrational frequencies, and chemical shifts were
calculated by using the methods of density functional theory (DFT) with B3LYP and
B3PW91 as functionals and Hartree-Fock with 6-311G++(d,p) as basis set using the
GAUSSIAN 09 program package. With the VEDA 4 software, the vibrational frequencies
were assigned in terms of the potential energy distribution (PED). The equilibrium
geometries calculated by all methods were compared with X-ray diffraction results,
indicating that the theoretical results matches well with the experimental ones. The data
obtained from the vibrational analysis and the calculated NMR are consistent with the
experimental spectra.
KEYWORDS: Schiff bases, Pyrazole, DFT, Hartree-Fock, NMR, FT-IR.

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1
.
Introduction
Schiff bases are an important class of organic compounds with significant biological and
chemical activities. Several Schiff base bearing N-heterocyclic groups in their structures
have received much attention in biological processes because they have shown a number of
properties like antimicrobial [1], antifungal [2], antituberculous [3], antitumoral [4],
antiparasitic [5] and antiviral [6] activity. They also have been considered as useful
synthetic building blocks in coordination chemistry because of their chelating effects [7].
Regarding to our interest in developing new structures from pyrazole derivatives, the new
Schiff base (4-OHFPz) was synthesized because of imines and pyrazole compounds have
chemical and biological properties, also 4-OHFPz will later be coordinated to palladium.
This Pd-Schiff base complex will be evaluated in C-C coupling reactions as well as
potential antifungal and anticancer agents. The crystal structure, the vibrational and
electronic spectra are reported in this work. The vibrational frequencies and the geometric
parameters of the compound mentioned in the ground state were calculated by ab initio
(
HF) and DFT (B3LYP, B3PW91) methodologies with the standard basis set 6-
11G++(d,p). A detailed interpretation of the vibrational spectrum of the aforementioned
compound was made on the basis of the calculated potential energy distribution (PED). The
3
1
13
H and C NMR spectra were calculated with ab initio and DFT by the GIAO method
from the optimized geometries, with tetramethylsilane (TMS) as standard and DMSO as
solvent. To calculate the HOMO and LUMO energies and the absorption spectrum, the TD-
SCF (Time-dependent self-consistent field) method was used by using the structure
optimized with the basis set 6-311G++ (d, p) in acetonitrile as solvent.
2
.
Experimental
2
.1.
Analytical and physicochemical measurements
Synthesis of 4-OHFPz was monitored by thin-layer chromatography (TLC) using silica gel
plates 60 F254 (Merck), visualization was achieved by ultraviolet (UV) light. Melting
points were determined on a Büchi melting point apparatus. Infrared spectra were taken on
a Perkin Elmer FT 2000 series spectrophotometer using KBr disks. Nuclear magnetic
resonance spectra were recorded on a Bruker Avance 400 spectrophotometer operating at
1
13
4
00 MHz for H and 100.61 MHz for C, using DMSO-d as solvent and tetramethylsilane
6

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as an internal standard. Chemical shifts (
δ
) are in ppm, coupling constants (J) are in Hertz
(Hz), and the classical abbreviations are used to describe the signal multiplicities.
Microanalyses were performed on an Agilent CHNS elemental analyzer and the values are
within ± 0.4% of the theoretical values. The mass spectrum was obtained on a
SHIMADZU-GCMS 2010-DI-2010 spectrometer equipped with a direct inlet probe
operating at 70 eV. High-resolution mass spectrum (HRMS) was recorded on an Agilent
Technologies Q-TOF 6520 spectrometer via electrospray ionization (ESI). The UV-Vis
absorption spectrum of 4-OHFPz was obtained in a solution of acetonitrile at room
temperature in the range of 200 to 600 nm with a Shimadzu UV-Vis 160A
spectrophotometer.
2
2
.2.
Synthesis
.2.1. Synthesis of 3-tert-butyl-1-phenyl-1H-pyrazole-5-amine (1)
Compound 1 was synthesized by following reported methodologies [8,9]. Phenylhydrazine
2.1220 g, 19.62 mmol) and 4,4-dimethyl-3-oxopentanenitrile (1.8502 g, 14.78 mmol) were
(
added into a solution of concentrated hydrochloric acid (4 mL) in water (32 mL). The
mixture was heated to 70 °C under constant stirring for 1 h. Then, concentrated
hydrochloric acid (4 mL) was added and the mixture was further heated for 1 h. The
reaction mixture was cooled in an ice bath and the solution was neutralized with
ammonium hydroxide, with the formation of a precipitate. The solid formed was filtered
under vacuum and washed with water (5 x 50 mL). The starting precursor 1 was obtained in
7
6.1% yield as a light brown solid. Anal. Calc. for C13
9.52. Found: C% 72.78, H% 7.65; N% 19.65. IR ( ΚΒr, cm ):
301,=C-H 3062, νas CH 2962, νs CH 2869 C=N 1623, C=C 1565 cm , δas CH 1376
ω C=C 698. H NMR (DMSO-d ): δ 1.32 (s, 9H) H-5; 3.74 (s, 2H) NH ; 5.51
17 3
H N : C% 72.52, H% 7.96; N%
-1
1
ν
as NH
2
3440, ν NH
2
s
-1
3
ν
ν
,
3
3
,
3
1
τ =C-H 756
,
6
2
1
3
(
s, 1H) H-6; 7.30 (t, 1H) H-11; 7.45 (t, 2H) H-10; 7.54 (d, 2H) H-9 ppm. C NMR
DMSO-d ): δ 30.0 (C-5); 32.4 (C-4); 90.4 (C-6); 122.1 (C-9); 124.9 (C-10); 144.7 (C-8);
44.8 (C-11); 145.4 (C-7); 164.0 (C-3) ppm. The atoms were numbered according to
Supp. Inf. S1).
(
6
1
(

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2
.2.2. Synthesis of the title compound 4-OHFPz
A mixture of the aminopyrazole 1 (352.46 mg, 1.64 mmol), 4-hydroxybenzaldehyde (200
mg, 1.64 mmol) and glacial acetic acid (5 drops) was stirred for 10 min at room
temperature. After reaction was complete (monitored by TLC), the crude solid formed was
washed with cold water (5x20 mL) and filtered under vacuum to dryness, affording
compound 4-OHFPz as a beige solid in 97% yield. Single-crystals of compound 4-OHFPz
suitable for X-ray diffraction were grown by slow evaporation of an acetone solution at
room temperature. The synthetic procedure for 4-OHFPz is shown in Scheme 1.
Insert Scheme 1.
Anal. Calc. for C H N O: C% 75.17, H% 6.52, N% 13.28. Found: C% 75.21, H% 6.63,
2
0
21
3
+
+
N% 13.16. M.p: 155.3 °C. MS (70 eV) m/z (%) 319 (M , 83.43), 304 (M -15, 100), 262
+
+
-1
(
M -57, 3.49), 226 (M -93, 5.39), 77 (23.29), 57 (13.54). IR ( ΚΒr, cm ): ν O-H 3455.98,
3 s 3
ν C-H 3124.27 (pyrazole), ν C-H 3058.7 (aromatic), νas –CH 2962.27, ν –CH 2865.84,
1
ν –C=N 1618.06. H NMR (DMSO-d
6
): δ 1.34 (s, 9H, tBu-H, H-18); 6.48 (s, 1H, H-15);
3
3
3
6
.90 (d, 2H, J = 8.39 Hz, H-6); 7.33 (t, 1H, J = 7.41 Hz, H-11); 7.50 (t, 2H, J = 7.61 Hz,
1
3
H-10); 7.75 (bd, 4H, H-5 and H-9); 8.76 (s, 1H, H-7); 10.28 (bs, 1H, H-1). C NMR
DMSO-d ): δ 30.69 (tBuC, C-18); 32.66 (C-17); 90.91 (C-15); 116.40 (C-6); 123.86 (C-
); 126.51 (C-11); 127.61 (C-4); 129.09 (C-10); 131.49 (C-5); 140.00 (C-8); 151.01 (C-14);
(
6
9
1
1
61.46 (C-7); 161.69 (C-16); 161.77 (C-1). The atoms were numbered according to figure
.
2
.3. X-ray crystal structure determination
Crystal data for 4-OHFPz were deposited at CCDC with the reference number
CCDC 1549505. Single-crystal X-ray data for 4-OHFPz were collected at 143 K on
a Bruker APEX-II CCD diffractometer using MoKα radiation (0.71073 Å)
monochromated by graphite. Cell determination and final cell parameters were
obtained on all reflections using the Bruker SAINT software included in APEX2
software suite [10]. Data integration and scaling was carried out by using the Bruker
SAINT software [11].

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The structures were solved by SHELXS-2013 software and then refined by
SHELXL-2013 [12], included in WinGX [13] and Olex2 [14]. Non-hydrogen atoms
of the molecules were clearly resolved and their full-matrix least-squares refinement
with anisotropic thermal parameters was conducted. All hydrogen atoms were
stereochemically positioned and refined by the riding model [12]. Hydrogen atoms
of the water molecules were localized and fixed (with Uiso(H) = 1.5 Ueq) on the
density map. ORTEP diagram was prepared with Diamond program [15]. TOPOS
[
16], Mercury [17], and Diamond [15] programs were used in the preparation of the
artwork of the polyhedral and topological representations.
3.
Computational study
Molecular optimization, harmonic vibration frequency, NMR and energy studies were
calculated by ab-initio computational methods, such as Hartree-Fock (HF) and DFT, using
the hybrid of the functional density B3LYP and B3PW91 with the basis set 6-311G++(d,p)
and the Gaussian packet 09 [18] without any obstacle to geometry. Theoretical vibrational
spectra of 4-OHFPz were interpreted by means of Potential Energy Distributions (PED)
using the VEDA 4 program [19] and the percentage contribution of the frontier orbitals at
each transition of electronic absorption spectrum using GaussSum software [20].
4
.
Results and discussion
4
.1. Structural description.
Details of data collection and refinement are summarized in Table 1. The ORTEP diagram
for 4-OHFPz is shown in Figure 1.
Insert Table 1.
Insert Figure 1.
Compound 4-OHFPz crystallized in the monoclinic space group P21/n with one molecule
per asymmetric unit. This compound is formed by three groups around the pyrazole ring: (i)
one phenolamine group, which presents a torsion angle between the rings C3-C4-C14-N2=
4
2.44(3)⁰; (ii), one phenyl group with a torsion angle C12-C13-N2-N3=43.72(3)⁰, and

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finally, (iii) a tert-butyl l group (Table 1). A general search in the CCDC database [21] for
similar compounds formed from a three substituted pyrazole ring reveals 20 entries of
which 3 hits present a good agreement with the obtained compound 4-OHFPz. VAGYOS
[22] and VIKTAM [23] compounds present a similar arrangement around its pyrazole ring,
substituted by a phenolamine, a phenyl and a tert-butyl groups. These structures present
significatively differences in the tortion angles of the substituents (Figure 2), giving to this
compound a particular crystallographic arrangement. The compound MEJRAX [24]
recently reported, is a structural isomer of 4-OHFPz with a -OH group in orto position.
Unlike the compound 2-OHFPz which present intramolecular O-H···N, the compound 4-
OHFPz have this accessible group enable to form intermolecular interactions. Differences
in the OH position provokes structural and supramolecular changes as will be explained
below.
Insert Figure 2.
In this case, the supramolecular structure is formed by the O-H···N interaction between the
phenol group and one nitrogen atom of the pyrazole ring with a distance of 2.883(3) Å,
forming chains along [010] direction (Figure 3 a). The chains are joined by C-H···O and C-
H···π interactions with distances 3.612(3) and 3.591(4) Å along [100] and [001] directions,
respectively (Figure 3 b and c).
Insert Figure 3.
Another way to observe and quantify the supramolecular interactions is through the
Hirshfeld surface [25] and the finger print plots [26]. On the superfice of the Figure 4a, is
possible to observe in red colour, the region susceptible to form interactions or hydrogen
acceptor groups. As it was expected, the red regions are mainly targered on the OH, N and
CH groups involved in the intermolecular interaction. The contribution of each interaction
to the formation of the supramolecular structure are obtained from the fingerprint plots,
being the most important present in the Figure 4b.
Insert Figure 4.

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4
.2.
Molecular Geometry
Optimization of the geometry in the ground state was carried out by using the HF,
B3PW91, and B3LYP levels with the basis set 6-311G++ (d,p). Optimization of the
structures is presented in Figure 5. The geometric data obtained are given in Table 2,
compared to the experimental data.
Insert Figure 5.
Insert Table 2.
Experimental bond lengths C12-N3, C6-O1, and N4-N5 are observed at 1.277(3), 1.357(2),
and 1.370(2) Å, respectively; 1.257, 1.344, and 1.345 Å for the HF level; 1.282, 1.357, and
1
.346 Å for the B3PW91 level; and 1.283, 1.364, and 1.355 Å for the B3LYP level. In 4-
OHFPz, the experimental bond C6-O1 (1.357(2) Å) is a typical single bond that is slightly
longer than the calculated values in all methods. The experimental bond length of C12=N3
(1.277(3) Å) is in good agreement with the theoretical data of 1.257 Å HF, 1.282 Å
B3PW91 and 1.283 Å B3LYP. This result agrees with data reported by Wang et al., [27].
Experimental bond N4-N5 (1.370(2) Å) is a typical N-N single bond [28], consistent with
the theoretical data of 1.345 Å HF, 1.346 Å B3PW91, and 1.355 Å B3LYP. Experimental
bond C14-N3 (1.387(3) Å) is longer than C14-N4 (1.363(3) Å); this is because the
substituent groups are different [29].
Few differences exist between bond lengths (less than 0.16 Å) and calculated angles (less
than 3 degrees). By examining the dihedral angles, the differences are more significant
mainly in the rotation of the tert-butyl group, given that the differences between the atoms
involved oscillate between 1 and 60°, for example, the dihedral angle between C30-C29-
C28-N5 has a difference of 60° with respect to the methods employed by HF, B3PW91,
and B3LYP, which is due to the rotation of the tert-butyl group with the pyrazole nitrogen.
These results are supported by the structural superposition of the calculated and
experimental molecules (Figure 6). From this superposition, it is possible to calculate a
RMSD value, which is a measure of the degree of agreement between the experimental and

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calculated models. The obtained values show good agreement between experimental and
calculated models with values around 0.1 and 0.3.
Insert Figure 6.
4
.3. Vibrational analysis
Table 3 shows the list of wave numbers of the bands observed in the FT-IR spectra of 4-
OHFPz. The theoretical frequencies and intensities of the IR spectra were calculated via
the HF, B3PW91, and B3LYP methods. Usually, scale factors are inputs to change the
calculated frequency values. In our calculations, we introduced different scaling factors,
0
.899748 for HF, 0.957562 for B3PW91, and 0.960461 for B3LYP.
Insert Table 3.
The experimental FT-IR spectrum is shown in Supp. Inf. S2 and those calculated in Supp.
Inf. S3. Discrepancies between the calculated and experimental vibrational frequencies are
due to two fundamental reasons: first, the experimental frequencies correspond to the solid
phase of KBr and the calculated frequencies belong to the gas phase. Second, the
calculation has been made for an isolated molecule in the gas phase and the experimental
values include intermolecular interactions. This is the reason why a correction of calculated
frequencies is employed using a scaling factor for all HF, B3PW91, and B3LYP methods
[30].
4
.3.1. O-H and C-OH Vibrations
The OH group provides two normal vibrations, ν(O-H) and ν(C-O) [31]. A free hydroxyl
-1
group gives frequencies in the range of 3450-3700 cm [32]. The OH-bond vibration is
-1
observed in the experimental IR spectrum at 3455.98 cm and in the calculated values at
-1
-1
-1
3
760.95 cm for HF, 3721.99 cm for B3PW91, 3677.60 cm for B3LYP. In addition, the
PED analysis shows that this vibration frequency is a pure mode with 100% contribution.
Binil et al., [31] reported the vibration of the C-OH bond for [4-butyl-1-(4-hydroxyphenyl)-
-
1
2
-phenyl-3,5-pyrazolydinedione] at 1211 cm ; this vibration is observed in the

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-1
experimental IR at 1241.99 cm , which is consistent with the calculated values observed at
-1
-1
-1
1
250.65 cm for HF, 1251.90 cm for B3PW91, and 1239.95 cm for B3LYP. For
-1
paracetamol ν(C-O) was reported at 1240 cm [33].
.3.2. C-H Vibrations
The vibration frequency of the pyrazole C-H bond is observed in the experimental spectrum
4
-1
-1
-1
at 3124 cm and in the calculated values at 3059 cm for HF, 3149 cm for B3PW91 and
-1
3
133 cm for B3LYP. The PED for this signal is 99%, which shows that the signal was
assigned correctly.
-1
In aromatic molecules, the C-H stretching vibrations appear in the range of 3100-3000 cm
[32]. In our studies, the experimental frequency of aromatic C-H stretching appears at
-
1
-1
3
3
058.7 cm . These frequencies appear in the calculated values at 3032.15 cm for HF,
-
1
-1
106.64 cm for B3PW91 and 3029.29 cm for B3LYP.
-1
The aliphatic C-H groups appear below 3000 cm [34]. Asymmetric C-H stretching
-1
vibration of the tert-butyl group was experimentally observed at 2962.27 cm and for the
-1
-1
-1
theoretical values at 2924.18 cm (HF); 2985.30 cm (B3PW91); 2960.14 cm (B3LYP).
-1
The symmetrical C-H stretching vibration was experimentally observed at 2865.84 cm
-1
-1
-1
and at the theoretical values at 2843.20 cm (HF); 2915.96 cm (B3PW91); 2899.63 cm
B3LYP).
The symmetrical deformations [35] of the methyl groups appear in the 1380 ± 20 cm
region. For 4-OHFPz, the symmetrical deformation of the methyl groups is observed
(
-1
-1
-1
experimentally at 1357.71 cm , for the theoretical values are observed at 1394.60 cm for
-1
-1
HF, 1338.57 cm for B3PW91, and 1335.04 cm for B3LYP.
The substitution patterns of the aromatic rings can be identified by flexing out of the plane
-1
of the C-H bond in the range of 900-675 cm [32]. The characteristic vibrations of para-
-1
substituted aromatic rings have been observed at 838 cm in the experimental IR, 863.75
-1
-1
-1
cm for HF, 857.01 cm for B3PW91, and 859.61 cm for B3LYP.
4
.3.3. C-C Vibrations
-1
Generally, bands C=C have varying intensities and are observed at 1650-1430 cm [36]. In
our studies, experimental aromatic C=C stretching vibrations were observed at 1527.42,

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-
1
1
1
500.42, and 1448.35 cm ; for the calculated values, these appear at 1610.55, 1511.58, and
-1
-1
421.60 cm for HF; 1589.91, 1546.58, and 1425.24 cm for B3PW91; 1577.07, 1568.43,
-1
and 1430.13 cm for B3LYP, the experimental data agree with the theoretical values.
4
.3.4. C=N and N=N Vibrations
The most characteristic band of the Schiff base derivatives is a vibration of the C=N bond
-1
in the 1500-1700 cm region [37]. In our studies, this vibration is observed experimentally
-1
at 1618.06 cm , which is congruent with that reported by Wang et al., [27]. The theoretical
-1
-1
values calculated for the C=N bond are observed at 1682.53 cm for HF, 1633.25 cm for
-1
B3PW91, and 1603.01 cm for B3LYP.
-1
All imine compounds exhibit N-C stretching in the 1000-1350 cm region [37]. In the
-1
experimental IR is observed a band at 1141.71 cm , which is attributed to N-C stretching.
-1
-1
The calculated values show 1196.66 cm for HF, 1147.89 cm for B3PW91, and 1196.73
-1
-1
cm for B3LYP. Temel et al., [38] reported N-C stretching at 1184 cm for the Schiff base
E)-2-nitro-4-[(phenyl-imino)methylphenol], which is consistent with our results.
(
-1
The experimental N-N stretching band of the pyrazole ring was observed at 1141 cm , and
-1
-1
were calculated at 1196.66 cm for HF, 1147.89 cm for B3PW91, and 1196.73 for
B3LYP. For N-N stretching vibration, the results are in good agreement with the similar
compounds [39,40].
To see the similarity between experimental and theoretical values, frequencies were plotted
2
in correlation graphs. As shown in Supp. Inf. S4, the value of R is very close to 1.00,
therefore, it can be stated that little variation exists in the results and the behavior of the
experimental vibrations can be corroborated by both computational methods.
In the correlation graphs, the vibration of the hydroxyl group was not taken into account
because it presents a high deviation between the experimental values and the theoretical
values. The difference between these values arises as a result of the calculations which not
consider the interaction generated between the nitrogen atom of the pyrazole ring on the
phenol group, generating a relatively strong intramolecular hydrogen bond.

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4
.4.
NMR studies
1
13
The chemical shifts of H and C NMR were calculated with ab initio and DFT through
the GIAO method [41,42] from the optimized geometries, with tetramethylsilane (TMS) as
1
13
standard and DMSO as solvent. The experimental and theoretical H and C chemical
shifts in DMSO-d solution are collected in Table 4 (the atoms were numbered according to
6
1
13
Figure 5). The experimental H and C NMR spectra of the studied molecule are shown in
2
1
Supp. Inf. S5 and Supp. Inf. S6 respectively. The correlation coefficient (R ) of H NMR
chemical shifts is 0.9926 for HF, 0.9950 for B3PW91 and 0.9924 for B3LYP (Supp. Inf.
2
13
S7), and (R ) of C NMR chemical shifts is 0.9959 for HF, 0.9981 for B3PW91 and
0
.9974 for B3LYP (Supp. Inf. S8).
Insert Table 4.
1
4
.4.1. H NRM
Experimental and calculated chemical shifts of 4-OHFPz are presented in Table 4. In the
1
H NMR spectrum of the title compound appears 8 signals that integrate for twenty one
protons. The NMR chemical shifts of aromatic protons of organic molecules are usually
1
observed in the range of 7.00–8.00 ppm, in the experimental H NMR spectrum, chemical
shifts in aromatic protons were observed between 6.9 and 7.75 ppm, while those calculated
were obtained between 6.55 and 8.26 ppm (HF); 7.34 and 8.58 ppm (B3PW91); 6.90 and
8
.39 ppm (B3LYP). The values calculated are higher and have different values compared to
the experimental value; this may be due to the effects of the DMSO solvent. It was
observed that the highest deviation in the experimental chemical shift from the values
calculated (δ -δtheo) was 6.22 ppm (H-2) with HF. The differences with the B3PW91 level
exp
were 5.31 ppm (H-2) and 5.41 ppm (H-2) for B3LYP. This can be attributed to the
overestimated paramagnetic contribution in the DFT calculations (B3PW91 and B3LYP)
[43], given that having a higher level of theory better describes the electronegativity effect
and the low field displacement of said atom, otherwise it happens with ab initio (HF)
calculation, because having a lower level of theory does not take into account the
electronegativity effect.

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1
3
4
.4.2. C NRM
1
3
Fourteen signals for eighteen carbon atoms are observed in the experimental C NMR
spectrum of 4-OHFPz. The aromatic carbons give signals in the overlapped areas of the
spectrum with chemical shift values from 100 to 150 ppm [44,45]. Similarly, chemical
shifts were observed in the values calculated between 151.52 and 104.09 ppm (HF), 161.74
and 115.13 ppm (B3PW91), 167.25 and 119.04 ppm (B3LYP). Due to the effect of an
electron-withdrawing group, the chemical shift will be at low field, therefore, it was
observed that the deviations of the chemical displacements calculated respect to the
experimental ones in the C-6 and C-15 (δ -δ ) carbons were 7.25 ppm (HF), 0.03 ppm
exp teo
(B3PW91) and 5.48 ppm (B3LYP) for C-6, due to the electronegativity property of the
oxygen atom. Deviations for the C-15 atom were 4.91 ppm for HF, 1.39 ppm for B3PW91
and 6.62 ppm for B3LYP due to the electronegativity property of the nitrogen atom. In
1
13
general, the experimental results of H and C NMR with the level DFT / 6-311G++ (d, p)
represent a better approximation to the data observed experimentally.
4
.5.
Electronic properties
The time-dependent density functional theory (TD-DFT) method is used to calculate the
UV-Vis spectrum. In addition, electron-absorption spectra were calculated using the Time-
Dependent Self-Consistent Field (TD-SCF) method by using the optimized structure with
the base set 6-311G++(d,p) in acetonitrile as solvent.
Insert Figure 7.
The experimental UV-Vis spectrum for 4-OHFPz (See Figure 7) shows four absorption
-1
-1
-1
-1
bands at 197 nm (ε = 74700 L mol cm ) 234 nm (ε = 44683 L mol cm ), 298 nm (ε =
-1
-1
-1
-1
3
6640 L mol cm ) and 334 nm (ε = 46518 L mol cm ) in CH CN. The absortion bands
3
at 197, 234 and 298 nm are assigned to π→π * transition associated to the aromatic rings
pyrazole and phenyl) and the band at 334 nm is assigned to π→π * transition within the
C=N azomethine group [32].
(
Insert Table 5.
The experimental UV-Vis spectrum shows four different possible transitions, with a
maximum absorption at 334, 298, 234 and 197 nm, respectively. From the calculated values

ACCEPTED MANUSCRIPT
(See Table 5), three transitions appear at 258.31, 221.95, and 219.45 nm for HF; 353.02,
3
21.21, and 292.77 nm for B3PW91; and 355.15, 324.53, and 293.57 nm for B3LYP in the
gas phase. The oscillator strength for the respective theoretical transitions are 0.7915,
.0164, and 0.0106 for HF; 0.8065, 0.1054, and 0.1080 for B3PW91; and 0.8050, 0.1019,
and 0.0983 for B3LYP.
0
(A) The band observed at 334 nm was compared to the theoretical data 258.32 nm (HF),
3
53.02 nm (B3PW91) and 355.15 nm (B3LYP). The strength of the oscillator for the
theoretical values were 0.7915 (HF), 0.8065 (B3PW91) and 0.8050 (B3LYP). The band
was classified as a possible HOMO → LUMO transition with a contribution percentage of
9
6%.
B) The band observed at 298 nm was compared to the theoretical data 221.95 nm (HF),
21.21 nm (B3PW91) and 324.53 nm (B3LYP). The strength of the oscillator for the
(
3
theoretical values were 0.0164 (HF), 0.1054 (B3PW91) and 0.1019 (B3LYP). The band
was classified as a possible HOMO-1 → LUMO transition with a contribution percentage
of 96%.
(C) The band observed at 234 nm was compared to the theoretical data 219.45 nm (HF),
2
92.77 nm (B3PW91) and 293.57 nm (B3LYP). The oscillator strength for the theoretical
values were 0.0106 (HF), 0.1080 (B3PW91) and 0.0983 (B3LYP). The band was classified
as a possible HOMO-2 → LUMO transition with a contribution percentage of 62%.
The frontier molecular orbitals HOMO and LUMO play a key role in the study of electrical
and optical properties. The highest occupied molecular orbital (HOMO) and the lowest
unoccupied molecular orbital (LUMO) can determine how the molecule interacts with other
species [46]. The HOMO represents the ability to donate an electron, and the LUMO to
accept an electron [47]. The difference in energy of a frontier orbital allows characterizing
the chemical reactivity and stability of the molecule. A molecule with a small difference in
the orbital energy is generally more reactive [48]. That is, a small interval between HOMO-
LUMO implies low kinetic stability and high chemical reactivity, as it is energetically
favorable to add electrons to a high LUMO and to extract electrons from a low HOMO.
Among many other uses, the energy difference between HOMO and LUMO has been used

ACCEPTED MANUSCRIPT
to predict the activity and intramolecular charge transfer in organic molecules with
conjugated π bonds [49,50].
Insert Figure 8.
From Fig. 8a, 8b, and 8c, it can be seen that HOMO is evenly distributed in the central
segment and on the phenol and pyrazole rings; whereas LUMO (Figure 8b, 8c) is
distributed similarly to HOMO, except that its distribution is partial in the pyrazole ring.
The HOMO-1 is distributed over the pyrazole and phenyl rings and partially over the tert-
butyl group (Figure 8a, 8b, 8c). The LUMO+1 shows an increase in the distribution on the
phenol and phenyl rings. This orbital also shows a partial distribution on the pyrazole ring
and a null distribution in the tert-butyl group. The LUMO and LUMO+1 (8a) show null
distribution throughout the molecule, which agrees with the pyrazole electron donor
capacity.
4
.6. Molecular electrostatic potential (MEP)
The molecular electrostatic potential (MEP) was investigated through HF and DFT
theoretical calculations at the 6-311G++ (d,p) level. The MEP is related to the electronic
density and it is a very useful descriptor in understanding sites for electrophilic attack and
nucleophilic reactions, as well as hydrogen bonding interactions, also it provides a visual
method to understand the relative polarity of the molecule [51]. The different values of the
electrostatic potential at the surface are represented by different colors; red represents
regions of highest electronegative electrostatic potential; blue represents regions of the
most positive electrostatic potential; and green represents a region of zero potential.
Potential decreases in the red > orange > yellow > green > blue order [52]. Negative
regions are usually associated with the lone pair of electronegative atoms [53]. As seen
from the MEP of the title molecule (Figure 9) for all methods, regions with negative
potential are over the electronegative atoms (oxygen atom of the hydroxy group and
nitrogen atom of the pyrazole). Thus, it can be predicted that a metal would preferentially
attack 4-OHFPz at the N-5 position.
Insert Figure 9.

ACCEPTED MANUSCRIPT
4
.7.
Global reactivity descriptors
The energy difference between HOMO and LUMO is an important chemical stability
index. A small HOMO-LUMO gap automatically means small excitation energies to the
manifold of excited states and a large HOMO-LUMO gap implies high stability with
respect to chemical reaction [54]. The HOMO and LUMO energies, energy gap (ꢀE),
ionization potential (IP), electron affinity (EA), absolute electronegativity (χ), absolute
hardness (η), absolute softness (σ), chemical potential (µ), and electrophilicity index (ω)
for 4-OHFPz have been calculated at HF, B3PW91 and B3LYP/6-311G++ (d,p) basis set
(
Figure 8) and the results are given the Table 6.
Insert Table 6.
According to Koopmans' theorem [55] ionization potential (IP) and electron affinity (EA)
can be expressed through HOMO and LUMO orbital energies: Ionization potential (IP) = -
EHOMO, Electron affinity (EA) = -ELUMO.
The electronegativity (χ), defined by Mulliken [56] as the average of (IP) and (EA):
ꢁ
ꢂ + ꢃꢄ
2
ꢀ
=
The hardness of a molecule is related to the gap between the HOMO and LUMO orbitals.
The larger the HOMO-LUMO energy gap the harder the molecule will be [57]. Chemical
hardness can be calculated as follows:
ꢁ
ꢂ − ꢃꢄ
2
ꢅ =ꢆ
Global softness is the inverse of global hardness [58]:
1
ꢇ =
ꢅ

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The electron affinity in combination with ionization energy can also yield chemical
potential (µ) defined by Parr and Pearson [59] as the characteristic of molecule
electronegativity:
−
(ꢁꢂ + ꢃꢄ)
2
ꢈ =
Parr et al.,[60] have introduced the global electrophilicity index (ω) which measures the
propensity of a species to accept electrons. It can be calculated by using the electronic
chemical potential (µ) and chemical hardness (η):
ꢈꢊ
ꢉ =
2ꢅ
The small η value is an indicator of the dominance of the electron donating group in the
molecular system. ꢁ is known by an opposite behavior to that of η, so the high value of this
parameter is also an indicator of electron donor groups [61].
The frontier orbital energy gaps (EHOMO-ELUMO) of 4-OHFPz are found to be 9.3789 eV for
HF, 3.9257 eV for B3PW91 and 3.9103 eV for B3LYP in the gas phase. The global
softness of the molecule is 0.2132 eV for HF, 0.5094 eV for B3PW91 and 0.5114 eV for
B3LYP whereas hardness is 4.6894 eV for HF, 1.9628 eV for B3PW91 and 1.9551 eV for
B3LYP which indicate the molecule is relatively hard so it tends to undergo changes or
reactions easily. Considering, the chemical hardness, a large HOMO–LUMO gap means a
hard molecule and small HOMO–LUMO gap means a soft molecule. One can also relate
the stability of the molecule to hardness, which means that the molecule the smallest
HOMO–LUMO gap means it is more reactive [62]. GAUSSIAN 09 [18] has been used to
construct the shapes of frontier molecular orbitals.

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4
.8.
Non Linear optical (NLO) property study by computational method
Quantum chemical calculations have been shown to be useful in the explanation of the
relationship between the electronic structure of the systems and its nonlinear optical
properties [63]. Urea is one of the prototypical molecules used in the study of the NLO
properties of molecular systems. Therefore it has been used frequently as a threshold value
for comparative purposes [64]. The calculations of the total molecular dipole moment (ꢀ),
linear polarizability (α) and first-order hyperpolarizability (β) were calculated by
DFT/B3LYP method with 6-311G++ (d,p) basis sets using Gaussian 09 program package.
Insert Table 7.
The total molecular dipole moment of 4-OHFPz from B3LYP with 6-311G++(d,p) basis
set is collected in Table 7. The total molecular dipole moment of 4-OHFPz from this basis
set is 3.0992D, which is 1,726 times higher than the value of urea (ꢀ = 1.3732 D). Similarly
-30
the first order hyperpolarizability of 4-OHFPz is 3.8298 x 10 esu which is 3.458 times
-30
higher than the value of urea (β= 0.372 x 10 esu). Our title molecule with higher dipole
moment and hyperpolarizability value than urea shows that the molecule has large NLO
optical property. As seen in Table 7, βyyz component is dominated, having a certain
dominant component means that there is a significant charge transfer in this direction.
5
.
Conclusion
4
-((3-(tert-Butyl)-(1-phenyl)pyrazole-5-yl)imino)methyl)phenol
(4-OHFPz)
was
1
13
synthesized and characterized through different techniques, like H NMR, C NMR, DEPT
1
35, 2D NMR (HSQC, HMBC), FT-IR, UV-Vis, MS and single-crystal X-ray diffraction.
Vibration frequencies were calculated by using the HF and DFT methods (B3LYP and
B3PW91) with 6-311G++(d,p) as the basis set. The title molecule was crystallized in the
monoclinic space group P21/n with one molecule per asymmetric unit. The data obtained
via X-ray diffraction and computational calculations indicate that good correlation exists
among these data. To predict the reactive sites for electrophilic and nucleophilic attack for
the 4-OHFPz molecule, the MEP at the optimized geometry was calculated.

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Acknowledgement
The authors are grateful to Universidad del Valle, Universidad Santiago de Cali and
Universidad del Quindío for financial support to project 789, as well as the contribution by
Dr. Ruben Toscano, from the Institute of Chemistry at UNAM (Mexico), in the
development of the research.
Appendix
Supplementary crystallographic data for this article is available in: [Optimized and
experimental geometries, experimental and theoretical FT-IR spectrum, correlation graphic
of the calculated and experimental IR and NMR frequencies]. Cambridge Crystallographic
information (CCDC 1549505). It can be obtained free of charge via
http://www.ccdc.cam.ac.uk/.
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ACCEPTED MANUSCRIPT
TABLES.
Table 1. Crystallographic data and refinement parameters for 4-OHFPz.
Compound
Emp. Formula
FW (g/mol)
Temp. (K)
λ (Å)
Crystal system
Space Group
Unit cell
a (Å)
4-OHFPz
C H N O
20 21
3
3
19.4
98
.71073
2
0
Monoclinic
P21/n
11.530(3)
12.717(4)
12.327(3)
b (Å)
c (Å)
α(⁰)
β(⁰)
9
0
1
03.890(5)
9
0
γ(⁰)
Volume (Å )
3
1754.5(8)
4
Z
3
1
0
.209
.076
ρ calcd (mg/m )
Abs.Coeff (mm )
F(000)
-
1
680
2.17 to 27.10
θ range (˚)
Reflections collected /27019 / 3866
Unique [R(int)]
[0.0604]
9
9
Completeness (%)
Data / restraints
3866 / 0 /
/
parameters
Gof on F
223
2
1.029
R1 [I>2σ(I)]
wR2[I>2σ(I)]
0.0579
0.1410

ACCEPTED MANUSCRIPT
Table 2. Optimized and experimental geometries of 4-OHFPz in the ground state.
Experimental HF/6-311++G (d,p) B3PW91/6-311++G B3LYP/6–311++G
a
Parameters
Bond Lengths (
(
∆
*)
(
∆
*)
(d,p)
(∆
*)
(d,p) (∆*)
Ǻ
)
1
355 (15)
.364 (7)
.401 (17)
.086
.385 (15)
.083
.405 (17)
.283 (6)
.097
N(5)-N(4)
C(6)-O(1)
1.370 (2)
1.357 (2)
1.384 (3)
0.930
1.345 (25)
1.344 (13)
1.391 (7)
1.077
1.346 (24)
1.357 (0)
1.399 (15)
1.087
1
1
1
1
C(7)-C(6)
1
H(8)-C(7)
C(9)-C(7)
1.370 (3)
0.931
1.378 (8)
1.074
1.383 (13)
1.084
1
H(10)-C(9)
C(11)-C(9)
C(12)-N(3)
H(13)-C(12)
C(14)-N(4)
C(14)-N(3)
C(15)-N(4)
C(16)-C(15)
H(17)-C(16)
C(18)-C(16)
H(19)-C(18)
C(20)-C(18)
H(21)-C(20)
C(22)-C(6)
H(23)-C(22)
C(24)-C(22)
H(25)-C(24)
C(26)-C(14)
H(27)-C(26)
C(28)-N(5)
C(29)-C(28)
C(30)-C(29)
H(31)-C(30)
H(32)-C(30)
H(33)-C(30)
C(34)-C(29)
H(35)-C(34)
H(36)-C(34)
H(37)-C(34)
C(38)-C(29)
H(39)-C(38)
H(40)-C(38)
1.388 (3)
1.277 (3)
0.930
1.393 (5)
1.257 (20)
1.086
1.402 (14)
1.282 (5)
1.098
1
1
1
1
.377 (14)
.377 (10)
1.363 (3)
1.387 (3)
1.426 (3)
1.373 (3)
0.930
1.350 (13)
1.386 (1)
1.418 (8)
1.385 (12)
1.072
1.373 (10)
1.373 (14)
1.417 (9)
1.394 (21)
1.082
1
.423 (3)
1
1
1
1
.396 (23)
1
.080
.393 (12)
.084
.393 (30)
.084
.396 (10)
.083
.387 (9)
.085
.392 (20)
,077
1.381 (3)
0.930
1.385 (4)
1.075
1.391 (10)
1.085
1
1.363 (4)
0.930
1.384 (21)
1.075
1.391 (28)
1.085
1
1.386 (3)
0.930
1.386 (0)
1.074
1.394 (8)
1.084
1
1
1.378 (3)
0.930
1.381 (3)
1.077
1.385 (7)
1.086
1
1
1.372 (3)
0,930
1.368 (4)
1,069
1.390 (18)
1,078
1
1
.334 (1)
.521 (12)
.545 (35)
1.335 (3)
1.509 (3)
1.510 (4)
0.961
1.298 (37)
1.518 (9)
1.539 (29)
1.087
1.332 (3)
1.515 (6)
1.538 (28)
1.095
1
1
1
1
1
.095
.094
.091
0.960
1.086
1.094
0.960
1.086
1.092
1
1
.539 (24)
1.515 (4)
0.960
1.539 (24)
1.086
1.532 (17)
1.094
1
1
1
.094
.094
.094
0.960
1.086
1.094
0.960
1.087
1.094
.544 (47)
1.497 (4)
0.960
1.534 (37)
1.084
1.538 (41)
1.094
1
1
.094
.095
0.960
1.087
1.095

ACCEPTED MANUSCRIPT
1
.092
.395 (24)
,084
.391 (17)
.082
H(41)-C(38)
C(42)-C(20)
H(43)-C(42)
C(44)-C(15)
H(45)-C(44)
0.960
1.084
1.386 (15)
1,075
1.092
1.392 (21)
1,085
1
1
1.371 (4)
0.930
1
1.374 (3)
0.930
1.383 (9)
1.073
1.388 (14)
1.083
1
Bond angles (°)
1
1
1
1
1
1
22.47
20.03
19.85
20.52
20.69
21.64
C(7)-C(6)-O(1)
C(9)-C(7)-C(6)
122.70 (2)
119.91 (2)
120.0
122.21
119.92
119.99
120.19
120.66
121.49
30.15
122.45
120.06
119.85
120.64
120.67
121.68
29.84
H(8)-C(7)-C(6)
H(10)-C(9)-C(7)
C(11)-C(9)-C(7)
119.12
121.72 (19)
119.35
H(13)-C(12)-N(3)
C(14)-N(4)-N(3)
C(16)-C(15)-N(4)
H(17)-C(16)-C(15)
C(18)-C(16)-C(15)
H(19)-C(18)-C(16)
C(20)-C(18)-C(16)
H(21)-C(20)-C(18)
C(22)-C(6)-O(1)
H(23)-C(22)-C(6)
C(24)-C(22)-C(6)
H(25)-C(24)-C(22)
C(26)-C(14)-N(4)
H(27)-C(26)-C(14)
C(28)-N(5)-N(4)
C(29)-C(28)-N(5)
C(30)-C(29)-C(28)
H(31)-C(30)-C(29)
H(32)-C(30)-C(29)
H(33)-C(30)-C(29)
C(34)-C(29)-C(28)
H(35)-C(34)-C(29)
H(36)-C(34)-C(29)
H(37)-C(34)-C(29)
C(38)-C(29)-C(28)
H(39)-C(38)-C(29)
H(40)-C(38)-C(29)
H(41)-C(38)-C(29)
C(42)-C(20)-C(18)
H(43)-C(42)-C(20)
C(44)-C(15)-N(4)
2
9.83
119.45 (19)
119.93 (19)
119.92
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
21.16
20.00
19.55
19.29
20.59
20.25
17.42
19.11
19.43
19.26
05.97
26.39
06.16
19.85
09.21
10.31
10.97
10.74
10.49
11.59
11.55
09.89
09.25
10.99
10.31
10.74
19.49
20.12
18.66
121.03
120.10
119.72
119.38
120.48
120.26
117.59
119.28
119.29
118.98
106.96
126.94
106.74
122.12
109.05
110.31
111.58
110.89
109.12
110.94
111.67
110.26
110.77
111.33
109.60
111.36
119.48
120.11
118.85
121.17
119.97
119.49
119.28
120.60
120.24
117.50
119.08
119.45
119.28
105.89
126.49
106.12
119.80
109.11
110.32
110.99
111.69
110.43
111.59
111.54
109.89
109.16
111.01
110.33
110.68
119.51
120.13
118.58
120.20 (2)
120.13
119.70 (3)
119.81
117.93 (18)
119.90
120.10 (2)
119.43
106.77 (18)
127.08
105.10 (16)
121.03 (19)
108.12 (2)
109.38
109.50
109.51
110.40 (2)
109.38
109.41
109.46
110.73 (2)
109.43
109.46
109.52
120.21 (3)
119.69
119.80 (2)

ACCEPTED MANUSCRIPT
1
21.19
H(45)-C(44)-C(15)
Dihedral angles (°)
120.41
120.87
121.33
2
.17
-0.12
-179.87
179.66
H(8)-C(7)-C(6)-O(1)
-0.04
-179.92
179.88
-0.07
-0.13
-179.88
179.65
-0.17
-
177.82
C(9)-C(7)-C(6)-O(1)
1
78.41
H(10)-C(9)-C(7)-C(6)
C(11)-C(9)-C(7)-C(6)
-
0.18
0.005
79.67
179.91
0.84
-1.57
-0.85
-
H(17)-C(16)-C(15)-N(4)
C(18)-C(16)-C(15)-N(4)
H(19)-C(18)-C(16)-C(15)
C(20)-C(18)-C(16)-C(15)
H(21)-C(20)-C(18)-C(16)
C(22)-C(6)-O(1)-C(7)
H(23)-C(22)-C(6)-O(1)
C(24)-C(22)-C(6)-O(1)
H(25)-C(24)-C(22)-C(6)
C(26)-C(14)-N(4)-N(3)
H(27)-C(26)-C(14)-N(4)
C(29)-C(28)-N(5)-N(4)
C(30)-C(29)-C(28)-N(5)
H(31)-C(30)-C(29)-C(28)
H(32)-C(30)-C(29)-C(28)
H(33)-C(30)-C(29)-C(28)
C(34)-C(29)-C(28)-N(5)
H(35)-C(34)-C(29)-C(28)
H(36)-C(34)-C(29)-C(28)
H(37)-C(34)-C(29)-C(28)
C(38)-C(29)-C(28)-N(5)
H(40)-C(38)-C(29)-C(28)
H(41)-C(38)-C(29)-C(28)
C(42)-C(20)-C(18)-C(16)
H(43)-C(42)-C(20)-C(18)
H(45)-C(44)-C(15)-N(4)
H(45)-C(44)-C(42)-C(20)
0.04
0.13
1
179.33
179.19
-0.94
179.68
179.98
-0.85
179.71
-179.91
-0.89
-
-
-
179.57
179.90
-179.95
179.78
-1.74
-179.55
-179.95
-0.02
-179.55
-179.88
-0.02
-
-0.02
1
79.95
79.97
75.76
178.30
-179.43
173.90
-179.32
-177.55
90.073
-172.33
67.73
179.96
179.99
176.27
-176.76
-179.78
119.03
179.77
59.92
179.95
179.96
175.65
-177.36
-179.98
59.38
1
1
-
177.43
179.99
-
5
9.39
178.96
1.20
58.72
79.64
0.79
60.49
179.85
60.14
79.33
9.19
.01
179.75
.37
179.81
-
-178.86
61.26
6
-
-52.38
-150.61
58.65
-60.44
-121.54
60.31
-58.64
179.65
60.85
1
6
-
-61.34
178.65
-0.30
-60.10
-179.92
-1.22
-60.46
-179.79
-60.09
179.18
59.09
-
-
1
178.19
58.20
179.83
59.85
5
0
0.07
0.067
-0.01
-
-
-179.09
1.59
-179.75
0.39
-179.72
0.37
0
178.92
-179.87
-179.83