Sains Malaysiana 47(7)(2018): 1491–1499
http://dx.doi.org/10.17576/jsm-2018-4707-17
Synthesis, Structure and Density Functional
Theory (DFT) Study of a Rhenium(I) Pyridylpyrazole Complex
as a Potential Photocatalyst for CO2
Reduction
(Sintesis, Struktur dan Kajian
Teori Fungsi
Ketumpatan (DDFT) ke atas
Kompleks Renium(I)
Piridilpirazol sebagai Fotomangkin untuk Penurunan CO2)
WUN FUI
MARK-LEE1.,
YAN
YI
CHONG1., KUNG
PUI
LAW1,3.,
ISHAK
B. AHMAD1
& MOHAMMAD
B. KASSIM1,2*
1School of Chemical Sciences and
Food Technology, Faculty of Science and Technology, Universiti
Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia
2Institut Sel
Fuel, Universiti Kebangsaan Malaysia,
43600 UKM Bangi, Selangor Darul Ehsan, Malaysia
3School of Biosciences, No. 1 Jalan Taylor’s, 47500 Subang Jaya,
Selangor Darul Ehsan, Malaysia
Diserahkan: 17 September 2017/Diterima: 28 Februari 2018
ABSTRACT
The Re(I)
complex, [Re(PyPzH)(CO)3Cl]
where PyPzH = 2-(1H-pyrazol-3-yl)pyridine,
was successfully synthesised and characterised
with an infrared (IR), ultraviolet-visible (UV-Vis),
1H
and 13C nuclear magnetic resonance (NMR)
spectroscopies and X-ray crystallography. The IR spectrum
featured three n(C≡O),
n(N-H), n(C=N) and n(C=C) signals
at (1860-2020), 3137, 1614 and 1513 cm-1, respectively. The UV-Vis
spectrum of the complex exhibited ligand-centred
(π®>*) electronic excitations [lmax =
227 nm, ε = 1.942 x 104 M-1cm-1;
lmax =
292 nm, ε = 0.853 x 104 M-1cm-1]
and a metal-to-ligand charge transfer (MLCT) band [lmax = 331 nm, ε = 0.467 x
104 M-1cm-1].
The 13C and 1H-NMR spectra
exhibited the characteristic signals of the three C≡O
(189.0 – 199.0 ppm) and NH (14.84 ppm), respectively. The X-ray
structure of [Re(PyPzH)(CO)3Cl]
showed the crystal adopted a monoclinic system with a C2/c space
group [unit cell dimensions: a = 27.7422(14) Å, b = 11.1456(5)
Å, c = 9.2461(4) Å with α = γ = 90º and β = 92.552(2)º].
Density functional theory (DFT)
and time-dependent (TD) DFT calculations
were performed to investigate the optimised
structural geometry and electronic properties of the title complex.
The results showed that the highest-occupied molecular orbital
(HOMO)
was predominantly found on the dπ-orbitals of Re(I),
Cl and CO. While the lowest-unoccupied molecular orbital (LUMO)
was located on the PyPzH moiety. The
structural and photophysical properties of the [Re(PyPzH)(CO)3Cl] were established and
the reaction enthalpies for the dissociation of Cl atom in the
formation of [Re(PyPzH)(CO)3]• were
discussed in view of its potential application for photocatalytic
CO2 reduction.
Keywords: Crystal structure;
DFT;
photocatalytic CO2 reduction;
pyridylpyrazole; rhenium(I)
polypyridine
ABSTRAK
Kompleks Re(I) [Re(PyPzH)(CO)3Cl]
dengan PyPzH
= 2-(1H-pirazol-3-il)piridina telah
berjaya disintesis
dan dicirikan dengan
spektroskopi inframerah
(IR),
ultralembahyung-nampak (UV-Vis) dan
resonans magnet nukleus
(RMN)
13C
dan 1H dan kristalografi
sinar-X. Spektrum
inframerah menunjukkan kehadiran tiga jalur n(C≡O),
n(N-H), n(C=N) dan
n(C=C) masing-masing pada
(1860-2020), 3137, 1614 dan 1513 cm-1. Spektrum
UV-Vis kompleks menunjukkan
peralihan elektronik
berpusatkan ligan (π®>*)
[lmaks =
227 nm, ε = 1.942 x 104 M-1cm-1;
lmaks =
292 nm, ε = 0.853 x 104 M-1cm-1]
dan satu jalur peralihan caj logam kepada
ligan (MLCT) [lmaks =
331 nm, ε = 0.467 x 104 M-1cm-1].
Spektrum
RMN
13C
dan 1H masing-masing
menunjukkan isyarat
cirian untuk tiga
isyarat kumpulan
C≡O (189.0 - 199.0 ppm) dan NH (14.84 ppm). Struktur X-ray bagi hablur tunggal [Re(PyPzH)(CO)3Cl]
memberikan sistem
monoklinik dengan kumpulan ruang C2/c dengan dimensi sel unit sel a = 27.7422(14) Å,
b = 11.1456(5) Å, c = 9.2461(4) Å dengan
α = γ = 90º dan β = 92.552(2)º. Pengiraan
berdasarkan teori fungsi ketumpatan (DFT)
dan DFT bersandar
masa (TD)
telah dijalankan
untuk membangunkan struktur geometri optimum dan ciri elektronik
kompleks [Re(PyPzH)(CO)3Cl]. Keputusan
kajian menunjukkan
orbital molekul terisi dengan tenaga tertinggi
(HOMO)
disetempatkan pada
orbital-dπ Re(I), Cl dan CO manakala
orbital molekul tidak
terisi dengan tenaga
terendah (LUMO) terletak
pada moiety PyPzH.
Struktur dan sifat
fotofizikal kompleks
[Re(PyPzH)(CO)3Cl]
telah dikenal
pasti dan entalpi
tindak balas
untuk penguraian atom Cl untuk pembentukan [Re(PyPzH)(CO)3]• juga
dibincangkan untuk
aplikasi sebagai fotomangkin penurunan CO2 yang
berpotensi.
Kata kunci: DFT;
fotomangkin penurunan
CO2; piridilpirazol;
renium(I)
polipiridina; struktur
Kristal
RUJUKAN
Agarwal,
J., Johnson, R.P. & Li, G. 2011. Reduction of CO2 on
a tricarbonyl rhenium(I)
complex: Modeling a catalytic cycle. Journal of Physical Chemistry
A 115(13): 2877-2881.
Amoroso,
A.J., Thompson, A.M.C., Jeffery, J.C., Jones, P.L., McCleverty,
J.A. & Ward, M.D. 1994. Synthesis of the new tripodal ligand tris-[3-(2′-pyridyl)pyrazol-1- yl] hydroborate, and the crystal structure of its europium(III)
complex. Journal of the Chemical Society,
Chemical Communications 24: 2751-2752.
Becke, A.D. 1988. Density-functional exchange-energy approximation with correct asymptotic
behaviour. Physical Review
A 38(6): 3098-3100.
Becke, A.D. 1993. Density functional thermochemistry III the role of exact exchange.
Journal of Chemical Physics 98: 5648-5652.
Chou,
P.T. & Chi, Y. 2006. Osmium- and ruthenium-based phosphorescent materials:
Design, photophysics, and utilization
in OLED fabrication. European Journal of Inorganic Chemistry
17: 3319-3332.
Cossi,
M., Rega, N., Scalmani,
G. & Barone, V. 2003. Molecules in solution with the C-PCM
solvation model. Journal of Computational Chemistry
24(6): 669-681.
Davidson,
E.R. & Feller, D. 1986. Basis set selection for molecular calculations.
Chemical Reviews 86(4): 681-696.
Doherty,
M.D., Grills, D.C. & Fujita, E. 2009. Synthesis of fluorinated ReCl(4,4′-R2-2,2′-bipyridine)(CO)3 complexes
and their photophysical characterization
in CH3CN
and supercritical CO2. Inorganic Chemistry 48(5):
1796-1798.
Fui, M.L.W., Hang,
N.K., Arifin, K., Minggu,
L.J. & Kassim, M.B.
2016. Photocatalytic degradation of bromothymol blue with Ruthenium(II)
bipyridyl complex in aqueous basic solution.
AIP Conference Proceedings 1784(II): 1-6.
Fui, M.L.W., Hang,
N.K., Minggu, L.J., Umar, A.A. &
Kassim, M.B. 2012a. Determination
of band energy levels for tungsten nitrosyldithiolene.
Sains Malaysiana
41(4): 439-444.
Fui,
M.L.W., Minggu, L.J. & Kassim,
M.B. 2012b.
Photo-chemical properties of molybdenum dithiolene.
Sains Malaysiana
41(5): 597-601.
Gibson,
D.H. & He, H. 2001. Synthesis and properties of fac-Re(dmbpy)(CO)3CHO (dmbpy
= 4,4[prime or minute]-dimethyl-2,2[prime or minute]-bipyridine),
a possible intermediate in reductions of CO2 catalyzed
by fac-Re(dmbpy)(CO)3Cl.
Chemical Communications (20): 2082-2083.
Hawecker,
J., Lehn, J.M. & Ziessel, R. 1983. Combinations as homogeneous catalysts. Chemical Communications
536: 536-538.
Hehre,
W.J., Radom, L., Schleyer, P.V.R. &
Pople, J.A. 1986. Ab initio molecular
orbital theory. Accounts of Chemical Research 9:
399-406.
Kianfar,
E., Kaiser, M. & Knör, G. 2015. Synthesis, characterization and photoreactivity
of rhenium and molybdenum carbonyl complexes with iminopyridine
ligands. Journal of Organometallic Chemistry 799-800:
13-18.
Klein,
C., Baranoff, E., Grätzel,
M. & Nazeeruddin, M.K. 2011. Convenient synthesis
of tridentate 2,6-di(pyrazol-1-yl)- 4-carboxypyridine and tetradentate 6,6’-di(pyrazol-1-yl)- 4,4’-dicarboxy-2,2’- bipyridine ligands. Tetrahedron Letters 52(5): 584-587.
Komala,
T. & Khun, T.C. 2014. Biological carbon dioxide sequestration potential of Bacillus pumilus. Sains
Malaysiana 43(8): 1149-1156.
Lee,
C., Yang, W. & Parr, R. 1988. Development of the Colle-
Salvetti correlation energy formula
into a functional of the electron density. Physical
Review B 37(2): 785-789.
Mark-Lee,
W.F., Rusydi, F., Minggu,
L.J. & Kassim, M.B. 2017. Bis(Bipyridyl)-Ru(II)-1-benzoyl-3-(pyridine-2-yl)- 1H-pyrazole
as potential photosensitiser: Experimental
and density functional theory study. Jurnal
Teknologi 79(5-3): 117-123.
Mark-Lee,
W.F., Ng, K.H., Minggu, L.J., Umar,
A.A. & Kassim, M.B. 2013. A molybdenum
dithiolene complex as a potential photosensitiser
for photoelectrochemical cells.
International Journal of Hydrogen Energy 38(22): 9578-9584.
Miertuš,
S., Scrocco, E. & Tomasi,
J. 1981.
Electrostatic interaction of a solute with a
continuum. A direct utilization of Ab
initio molecular potentials for the prevision of solvent effects.
Chemical Physics 55(1): 117-129.
Ng,
K.H., Minggu, L.J., Mark-Lee, W.F.,
Arifin, K., Jumali, M.H.H. &
Kassim, M.B. 2018. A new method
for the fabrication of a bilayer WO3/Fe2O3
photoelectrode for enhanced photoelectrochemical
performance. Materials Research Bulletin 98: 47-52.
Ng,
K.H., Minggu, L.J., Jaafar,
N.A., Arifin, K. & Kassim,
M.B. 2017.
Enhanced plasmonic photoelectrochemical
response of Au sandwiched WO3 photoanodes. Solar Energy Materials and Solar Cells 172:
361-367.
Ng,
K.H., Minggu, L.J., Jumali,
M.H.H. & Kassim, M.B. 2012. Nickel-doped tungsten
trioxide photo electrodes for photoelectrochemical
water splitting reaction. Sains
Malaysiana 41(7): 893-899.
Obata, M., Kitamura,
A., Mori, A., Kameyama, C., Czaplewska, J.A., Tanaka, R., Kinoshita, I. Kusumoto, T., Hashimoto, H., Harada, M., Mikata, Y., Funabiki, T. & Yano,
S. 2008. Syntheses, structural characterization and photophysical
properties of 4-(2-pyridyl)-1,2,3-triazole
rhenium(I) complexes. Dalton Transactions 25: 3292-3300.
Pearce,
B.H., Ogutu, H.F. & Luckay,
R.C. 2017.
Synthesis of pyrazole-based pyridine
ligands and their use as extractants
for nickel(II) and copper(II): Crystal
structure of a copper(II)– ligand complex. European Journal
of Inorganic Chemistry 2017(8): 1189-1201.
Piletska,
K.O., Domasevitch, K.V., Gusev,
A.N., Shul’Gin, V.F. & Shtemenko,
A.V. 2015.
fac-Tricarbonyl
rhenium(I) complexes of triazole-based
ligands: Synthesis, X-ray structure and luminescent properties.
Polyhedron 102(I): 699-704.
Radaideh,
J.A., Alazba, A.A., Amin, M.N., Shatnawi,
Z.N. & Amin, M.T. 2016. Improvement of indoor
air quality using local fabricated activated carbon from date
stones. Sains Malaysiana 45(1):
59-69.
Sahara,
G. & Ishitani, O. 2015. Efficient photocatalysts for CO2 reduction.
Inorganic Chemistry 54(11): 5096-5104.
Seridi,
A., Wolff, M., Boulay, A., Saffon,
N., Coulais, Y., Picard, C., MacHura,
B. & Benoist, E. 2011. Rhenium(I) and
technetium(I) complexes of a novel pyridyltriazole-based
ligand containing an arylpiperazine
pharmacophore: Synthesis, crystal structures, computational studies
and radiochemistry. Inorganic Chemistry Communications 14(1):
238-242.
Tamaki,
Y. & Ishitani, O. 2017. Supramolecular photocatalysts for the reduction
of CO2. ACS Catalysis 7(5):
3394-3409.
Wun, F.M.L., Pui, L.K., Heng, L.Y. & Kassim, M. 2013. Molybdenum complex as potential
photosensitiser for direct water splitting. Materials
Science Forum 756: 231-237.
Yamazaki, Y.,
Takeda, H. & Ishitani, O. 2015. Photocatalytic
reduction of CO2 using metal complexes. Journal
of Photochemistry and Photobiology C: Photochemistry Reviews 25:
106-137.
Yilmaz, F., Balta,
M.T. & Selbaş, R. 2016. A review of solar based hydrogen
production methods. Renewable and Sustainable Energy Reviews
56: 171-178.
*Pengarang
untuk surat-menyurat;
email: mb_kassim@ukm.edu.my