New dioxido-vanadium(V) complexes containing hydrazone ligands: Syntheses, crystal structure and their catalytic application toward C–H bond functionalization

Article abstract of DOI:10.1016/j.jorganchem.2018.08.025

New dioxido-vanadium(V) complexes derived from hydrazone ligands have been synthesized in good yield. The complexes were characterized by elemental analysis, IR, UV–Visible and ¹H NMR spectroscopies. The structure of both the complexes was established by Single Crystal X-ray crystallography. Complex 1 crystallized in monoclinic P2₁/n space group, with cell parameters a = 8.3725(5) ? b = 15.0475(17) ? c = 32.227(3) ? α = 90° β = 91.846(5)^o, γ = 90°. Complex 2 crystallized in triclinic P-1 space group, a = 8.1871(7) ? b = 11.2605(17) ? c = 11.4031(18) ? α = 105.961(14)° β = 110.528(12)^o and γ = 96.387(10)^o. Both the complexes act as efficient catalyst which can catalyse the C–H bond functionalization reaction.

Full text of DOI:10.1016/j.jorganchem.2018.08.025

Accepted Manuscript
New dioxido-vanadium(V) complexes containing hydrazone ligands: Syntheses,
crystal structure and their catalytic application toward CH bond functionalization
Sunshine D. Kurbah, M. Asthana, Ibanphylla Syiemlieh, Alzelia A. Lywait, M.
Longchar, R.A. Lal
PII:
S0022-328X(18)30610-7
10.1016/j.jorganchem.2018.08.025
JOM 20552
DOI:
Reference:
To appear in: Journal of Organometallic Chemistry
Received Date: 10 July 2018
Revised Date: 20 August 2018
Accepted Date: 27 August 2018
Please cite this article as: S.D. Kurbah, M. Asthana, I. Syiemlieh, A.A. Lywait, M. Longchar, R.A. Lal,
New dioxido-vanadium(V) complexes containing hydrazone ligands: Syntheses, crystal structure and
their catalytic application toward CH bond functionalization, Journal of Organometallic Chemistry (2018),
doi: https://doi.org/10.1016/j.jorganchem.2018.08.025.
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1

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New dioxido-vanadium(V) complexes containing hydrazone ligands:
Syntheses, crystal structure and their catalytic application toward C-H
bond functionalization
Sunshine D. Kurbaha, M. Asthanab, Ibanphylla Syiemlieha, Alzelia. A. Lywaita, M.
Longchara and R. A. Lala*
aCentre for Advanced Studies in Chemistry, North-Eastern Hill University, Shillong-793022,
India.
bDepartment of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039,
India
Abstract
New dioxido-vanadium(V) complexes derived from hydrazone ligands have been synthesized
in good yield. The complexes were characterized by elemental analysis, IR, UV-Visible and
1H NMR spectroscopies. The structure of both the complexes was established by Single
Crystal X-ray crystallography. Complex 1 crystallized in monoclinic P21/n space group, with
cell parameters a = 8.3725(5) Å, b = 15.0475(17) Å, c = 32.227(3) Å, α = 90o, β = 91.846(5)o,
γ = 90o. Complex 2 crystallized in triclinic P-1 space group, a = 8.1871(7) Å, b = 11.2605(17)
Å, c =11.4031(18) Å, α = 105.961(14)°, β = 110.528(12)o and γ = 96.387(10)o. Both the
complexes act as efficient catalyst which can catalyse the C-H bond functionalization
reaction.
Keywords: Crystal structure, C-H activation, Vanadium(V) and DFT
1. Introduction
Vanadium is a trace element and biologically relevant metal which may be beneficial
and possibly essential in humans but certainly essential for some living organisms [1-3].
Vanadium ions are found to exist in many oxidation states such as V3+, V4+, and V5+ [4-7].
Among these three oxidation states, vanadium(V) compounds have received considerable
attention. Moreover, high valence vanadium V(V) and V(IV) complexes are pro-drugs that
release active components, such as vanadates or peroxido-vanadates when react with
biological media, which then act as potent inhibitors of protein tyrosine phosphatases and
altered cell signalling [8, 9]. The research interest on oxidation state of vanadium are very
4+
interesting not only due to its ability to exist in three different motifs viz., VO3+, V2O3 and
+
VO2 but also due to its involvement in many catalytic processes. The ability of vanadium to
switch easily between +IV and +V oxidation states and their relative stability, depend upon
the basicity of the ligands in which it coordinated [10, 11]. The ability of vanadium metal to

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possess variable oxidation states which are easily interconvertible, have high affinity for
oxygen and the Lewis acidic nature, extends its application in redox and Lewis acid catalyzed
reactions [12, 13].
Many vanadium complexes have been synthesized and characterized which act as a
catalyst for the oxidation of wide varieties of organic substrates such as oxidative C-H
activation, epoxidation, alcohol oxidation reactions, oxidative halogenation and sulfoxidation
by utilizing O2 and H2O2 [14-16]. C-H bond functionalization has emerged as a powerful
strategy for construction of more useful compound having C-C, C-X (C-F, C-Cl, C-Br and C-
I) or C-heteroatom bonds [17]. Due to its low cost and environmentally benign, many
vanadium compounds have been extensively used for the synthesis of many organobromines
through C-H functionalization [18]. Vanadium compounds utilized O2 as oxidants in most of
these processes, the catalysis vanadate/peroxovanadate catalysts in combination with the
reactive peroxides are carried out under strong acidic conditions.
2. Experimental
2.1. Materials and methods
The ligand was prepared as described in the literature [19]. All chemical were
1
13
reagents grade and solvents were reagent grade and used as received. The H NMR and C
NMR were recorded with a Bruker Avance II 400 & 100 MHz in DMSO-d6 solution using
TMS as an internal standard. Infrared spectra in the range 4000 - 200 cm-1 were recorded as
KBr discs by using a BX-III/ FTIR Perkin Elmer Spectrophotometer. Electronic spectra were
recorded on a Perkin-Elmer Lambda-25 spectrophotometer.
2.2. X-ray crystallography
Crystallographic data for the compound were measured at 291.8 K, using Xcalibur,
Eos, Gemini diffractometer equipped with a monochromated MoK radiation ((λ = 0.71073 Å)
source. The CrysAlis PRO; Agilent, 2013 software packages were used for data collection
and reduction, respectively [20]. In all cases absorption corrections based on multiscan using
SADABS software were applied [21]. SHELXT-2014 and SHELX-2014 were used for
structure solutions and refinements [22]. Crystallographic Data Centre, CCDC, 12 Union
Road, Cambridge CB21EZ, UK. Depository number CCDC-1839171, 1854787; E-Mail:
deposit@ccdc.cam.ac.uk, http://www.ccdc.cam.ac.uk).
2.3. Preparation of complexes
Vanadium(V) complex (0.32 g, 1 mmol) was dissolved in 20 mL of methanol. To this
solution vanadyl acetyl acetonate (0.265 g, 1 mmol) was added under stirring conditions for

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o
10 minutes. The reaction mixture was refluxed at 70 C for 1 h. The precipitate was then
filtered, washed and dried. The resulting solution was then cooled to room temperature which
yielded precipitate. Single crystals of the complex were obtained from DMF/water mixture
(2:3, v/v) by slow evaporation within a week.
2.4. VO2L1
Yield: 87 %. Anal (%), Calcd for C13H9BrN3O4V (MW 400 g/mol) C, 38.80; H, 2.21;
N, 10.42. Found: C, 38.81; H, 2.22; N, 10.40. IR data (cm-1 KBr): 1537 (vs) ν(N=CO-), 944
(s), 893 (s), ν(V=O). 1H NMR (400 MHz, DMSO-d6, Me4Si): δ (ppm): 9.26 (s, 1H, C(H)=N),
8.85-6.85 (m, 7H, Ar-H). Electronic spectrum (λmax, nm): 322, 421.
2.5. VO2L2
Yield: 90 %. Anal (%), Calcd for C13H9BrN3O4V (MW 400 g/mol) C, 38.80; H, 2.21;
N, 10.42. Found: C, 38.80; H, 2.21; N, 10.40. IR data (cm-1 KBr): 1601 (vs) ν(N=CO-), 935
1
(s), 914 (s), ν(V=O). H NMR (400 MHz, DMSO-d6, Me4Si): δ (ppm): 8.88, 8.66 (s, 1H,
C(H)=N),6.84-7.96 (m, 7H, Ar-H). Electronic spectrum (λmax, nm): 324, 416.
2.6. General experiment for oxidative bromination
In a 50 mL round bottom flask equipped with a magnetic stirring bar, 2-
hydroxyacetophenone (10 mmol) were added. To this solution, KBr (40 mmol) dissolved in
20 mL water was added and then dissolved by stirring at ambient temperature followed by
addition of a 30% H2O2 (4 mmol). To this reaction mixture, vanadium(V) complex (0.01
mmol) and 70% HClO4 (4 mmol) were added and the reaction mixture was stirred at 0 oC and
then after 10 minutes at room temperature. An additional 4 mmol of 70 % HClO4 was further
added in three equal portions after every 10 minutes with continuous stirring. In addition, all
the reactions were monitored using thin layer chromatography as a qualitative method. The
NMR spectra of bromination products are given in the supporting information.
3. Results and discussion
3.1. Spectroscopic studies
Scheme 1. Structure of ligands used in the present study.
Vanadium(V) complexes was prepared by reaction of hydrazone ligands with
vanadium pentoxide in 1:1 molar ratios in methanol. Complex 1 shows three new bands at

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-1
945 cm-1, 893 cm-1 and 1537 cm , the bands at 945 cm-1 and 893 cm-1 are assigned to V=O
stretching vibration and the band at 1537 cm-1 is assigned to newly created –N=CO
functional group. Similarly, complex 2 shows three important prominent bands at 1601 cm-1,
935 cm-1 and 914 cm-1, these bands are assigned to –N=CO functional group and V=O
stretching vibration [23]. The ligand shows resonances at
δ = 12.20-12.31 ppm and δ = 11.28-
11.13 ppm, these resonances are assigned to -OH and -NH protons respectively (Fig. S1 &
S2). The disappearance of these signals during complexation confirmed the ligand coordinate
to metal ions in deprotonated form i.e. enol form which are confirmed by IR studies, with the
absence of carbonyl stretching frequency (Fig. S3 & S4). The electronic spectrum of the
complex shows two absorption bands at 322 nm and 421 nm (complex 1) and 324 nm and
416 nm (complex 2) (Fig. S5 & S6). The band at 322 nm and 324 nm are assigned to intra-
ligand charge transfer whereas the band at 421 nm and 416 nm are assigned to ligand to metal
charge transfer transition [24].
3.2. X-ray crystallographic studies
The crystal data and structure refinement parameters for the complexes are given in
Table 1, whereas the molecular structure of the complex is given in Fig. 1 and Fig. 2,
respectively. Selected bond lengths and bond angles of the complex are summarized in Table
2. The ligand coordinates to metal ion in tridentate fashion through -ONO- donors and two
oxido ligands forming a penta- coordinated geometry around the metal center in both the
complexes.

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Fig. 1. Crystal structure of complex 1
Fig. 2. Crystal structure of complex 2
Complex 1, crystallized in monoclinic P21/n space group. The metal bond lengths in
the complex are 1.891(3) Å (V1-O1), 1.967(3) Å (V1-O2), 1.661(3) Å (V1-O3), 1.599(4) Å
(V1-O4), 1.980(3) Å (V1-O5), 1.915(3) Å (V1-O6), 1.660(3) Å (V1-O7), 1.601(4) Å (V1-
O8), 2.133(4) Å (V1-N1) and 2.165(4) Å (V1-N4), respectively. The geometrical bond angles
around vanadium ions are 105.19(18)o (O4-V1-O1), 95.27(16)o (O3-V1-O1), 146.58(16)o
(O1-V1-O2), 93.74(15)o (O3-V1-O2), 102.78(16)o (O4-V1-O2), 106.93(19)o (O4-V1-O3),
150.05(14)o, 74.20(14)o (O2-V1-N1), 149.08(18)o (O3-V1-N1), 81.75(15)o (O1-V1-N1),
103.52(17)o and (O4-V1-N1), 73.73(13)o. The trans angle in the complex are 146.58(16)o
(O1-V1-O2) and 149.08(18)o (O3-V1-N1) around V1 with τ = 0.042.
Complex 2, crystallized in triclinic P-1 space group. The vanadium-oxygen bond
distance in complex are 1.914(3) Å (V1-O1), 1.978(4) Å (V1-O2), 1.607(4) Å (V1-O3), and
1.634(4) Å (V1-O4), whereas the vanadium-nitrogen bond distance is 2.139(5) Å (V1-N1)
longer compare to V-O bond length in the complex. The metal-ligand bond angles in the
complex are O1-V1-O2 (153.3(17)o, O1-V1-N1 (82.35 (15)o, O2-V1-N1(73.68 (15)o, O4-V1-
O1 (97.09 (16)o, O4-V1-O2 (92.86 (17)o, O4-V1-N1 (137.27 (18)o, O3-V1-O1 (101.82 (19)o,
O3-V1-O2 (98.31 (19)o, O3-V1-O4 (108.5 (2)o and O3-V1-N1 (113.49 (18)o, respectively.
The trans angle in the complex are O1-V1-O2 (153.3(17)o and O4-V1-N1 (137.27 (18)o with
τ = 0.26. Hence, vanadium ions adopt a square pyramidal geometry with slight distortion in

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complex 1 compared to complex 2. The geometrical bond lengths and bond angles are in
good agreement with the literature reports [24].
3.3. Packing diagram of complexes
Molecular packing diagram of the complexes exhibit a weak hydrogen bonding
interaction. The molecular packing diagram through crystallographic a-axis is shown in Fig. 3
and Fig. 4.
Fig. 3. Packing diagram of complex 1 along a-axis showing hydrogen bonding
In complex 1, the N--H…O and O--H... N bond distances are 2.774 Å (N(8) --H(8A)
..O(3) and 2.896 Å (O(9) --H(9B) ..N(3) with bond angles of 173o (N(8) --H(8A) ..O(3) and
127o (O(9) --H(9B) ..N(3). The C--H…O bond distances are 3.167(7) Å (C(29) --H(29A)
..O(8), 3.470(10) Å (C(31) --H(31C) ..O(1) and 3.264(8) Å (C(32) --H(32A) ..O(4), with
geometrical bond angles 150o (C(29) --H(29A) ..O(8), 152o (C(31) --H(31C) ..O(1) and 129o
Å (C(32) --H(32A) ..O(4), respectively.

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Fig. 4. Molecular packing diagram of complex 2 along a-axis
The geometrical N--H…O and O--H... N bond distances in complex 2 are 2.722(7) Å
(N(4)--H(4A) ..O(4) and 2.756(7) Å (N(4)--H(4B) ..O(5) and 2.803(8) Å (O(5)--H(5B)
..N(3) with their bond angles 167o, 176o and 175o, respectively. The O--H…O bond length
and bond angle are 2.967(6) and 169o. The C--H…O bond distances are 3.331(7) Å (C(4)--
H(4)..O(4), 3.390(7) Å (C(7)--H(7)..O(3) and 3.425(9) Å (C(15)--H(15C) ..O(5), with bond
angles 144o and 153o.
3.4. Computational studies of complexes
Theoretical studies for the electronic structure of the complex in gas phase were
performed using density functional theory with hybrid functional B3LYP using GAUSSIAN
09 program [25]. The electronic geometry was calculated using 6-31+G(d,p) basis set for
carbon, hydrogen, oxygen, nitrogen and bromine atoms and for vanadium ion LANL2DZ
[26] basis set was used. Contour plots of selected molecular orbitals and their energy gap
(HOMO-LUMO) are shown in Figs. 5 & 6. The energy different between the HOMO and
LUMO in the complexes are 2.89 eV in complex 1 and 3.05 eV in complex 2, which are

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lesser compared to that of the corresponding ligands 3.89 eV and 3.72 eV. The compositions
of HOMO and LUMO are very useful in order to understand the absorption spectra of the
complexes as well as their nature of transition. A large energy gap between HOMO-LUMO
corresponds to a high energy required for electron excitation. Hence, energy for electron
excitation in the complexes are less compared to that of the ligand due to smaller energy gap.
In these two complexes the HOMO is composed of ligand π orbital and whereas the LUMO
is mainly composed of ligand π* orbital and vacant d-orbital of vanadium. The geometrical
bond lengths and bond angles optimized in gas phase are in good agreement with the
experimental data obtained from single crystal X-ray crystallography. Slight deviation was
observed, as a result geometrical optimization is performed in gaseous state in which
intermolecular interactions are absent and structure is more extended compared to X-ray
crystallography data.
Fig 5. Contour plots for some selected molecular orbitals of complex 1

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Fig 6. Contour plots for some selected molecular orbitals of complex 2
3.5. Catalytic studies
The catalytic studies for C-H bond functionalization was tested using stoichiometric
amount of the complex with organic substrates such as acetophenone and acetophenone
derivatives, 2-hydroxybenzaldehyde in presence of KBr, HClO4 and 15% H2O2.
Table 3. Optimization of reaction conditions for the oxidative bromination catalysed by
vanadium(V) complexes.
Entry
1
Molar ratio
Temperature Time
Isolated
yield (%)
(oC)
(min)
V-comlex: S
S: KBr
Br:H2O2
1:1
HClO4
(mmol)
2
1:10
1:2
RT
30
64
2
3
4
1:10
1:10
1:10
1:4
1:4
1:4
1:1
1:2
1:4
2
2
2
RT
RT
RT
30
30
30
70
82
79

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5
1:20
1:4
1:4
2
RT
30
56
6
7
8
9
1:05
1:10
1:10
1:10
1:4
1:4
1:4
1:4
1:4
1:4
1:4
1:4
2
2
2
2
RT
40
55
70
30
30
30
30
81
73
70
65
10
11
1:10
-
1:4
1:4
-
4
4
RT
RT
30
240
87
7.5
1:4b
aAll the reactions were carried out using 0.04 g catalyst (0.1 mmol), 2-hydroxyacetophenone
as substrate, KBr as bromide source, HClO4 (4.0 mmol) and H2O (5 mL) as solvent unless
stated.
bControl reaction: acetophenone (1.0 mmol), catalyst (0.1 mmol), KBr (4.0 mmol), HClO4
(4.0 mmol) and H2O (5 mL).
Scheme 1. Substrate scope and isolated yield.
Using our newly synthesized vanadium(V) complexes as catalyst, the reaction was
carried out using different molar ratios of complex, acetophenone, KBr and hydrogen
o
peroxide. The reaction mixture first was stirred at low temperature (0 C) and then after 10
minutes it was raised to room temperature. The effect of solvents was also tested by carrying
out the reaction using different solvents and it was found that water gave the best yield. The
catalytic studies were carried out using different molar ratios of complex/substrate/KBr and
hydrogen peroxide and it was found that 1:10:40:40 molar ratios of
complex/substrate/KBr/hydrogen peroxide gave the best yield. The effects of acid for the
oxidative bromination reaction were tested and found that 4 molar ratios of HClO4 gave
maximum yield (Table 3, entry 10). Control experiment were also performed using
stoichiometric amount of catalyst (0.1 mmol), acetophenone (1.0 mmol), KBr (4.0 mmol),
HClO4 (4.0 mmol) and H2O (5 mL) in the absence of an oxidant, but it was observed that,

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only a trace amount of product was obtained even after a period of 4 hr. The catalytic activity
of the complex 2 were also tested using the same reaction condition and it was found that
complex 2 can be also used as catalyst for catalytic reaction but its yield is almost similar to
complex 1. In the recent past, the bromination of many organic substrates by vanadium-based
catalysts has been extensively studied (Table 3). Maurya et al. studied the oxidative
bromination of salicylaldehyde using vanadium complexes having [VIVO]2+ and [VVO2]+
cores with binucleating dibasic tetradentate ligands, which show a maximum of 95.7% yield
of 5-bromosalicylaldehyde [27]. In their studies they have shown that increase in the
hydrogen peroxide concentration improves the conversion of salicylaldehyde. Further, in the
absence of catalyst the conversion of product was only 4%. Maurya et al. have also studied
the catalytic bromination reaction of salicylaldehyde using polymer-anchored dioxo-
vanadium(V) complexes, which shows a maximum conversion of 85% product (5-
brompsalicylaldehyde) [28]. In their studies, they also reported that when Chloromethylated
polystyrene supported oxo-vanadium(IV) complexes are used as catalysts in the oxidative
bromination of salicylaldehyde, the formation of product (5-bromosalicylaldehyde) was 73%
and in this case dibrominated product was also formed [29].
Manirul Islam et al. reported the catalytic oxidative bromination of salicylaldehyde
using polymer anchored oxovanadium complex (PS-tetaeVO) with 98% yield of 5-
bromosalicylaldehyde (Table 4). In their studies they showed that hydrogen peroxide plays a
very important role in the catalytic oxidative bromination, in the absence of hydrogen
peroxide the formation of bromo products was significantly less [30].
Table 4. Bromination of salicylaldehyde catalyzed by other vanadium-based catalysts
Catalyst
Yield %
Ref
Cs2[CH2{VVO2(sal-bhz)}2].2H2O
polymer-supported-K[VO2(sal-inh)(im)
polymer-supported-[VO(fsal-ohyba) DMF]
Polymer anchored oxovanadium complex (PS-tetaeVO)
95.7
85
73
27
28
29
30
98
Dioxido-vanadium(V) complexes containing hydrazone 90
ligands
This study
To explore the validity of this method other organic substrates were tested. Some
selected results are listed in scheme 1. The bromination reaction of salicylaldehyde gave 90%
yield of 5-bromo salicylaldehyde in 40 min. Inspired by these results, we hypothesized that
the α-bromoketone could be obtained using vanadium(V) complexes and acetophenone as the
substrate. In our study, we found that bromination of acetophenone gave α-

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bromoacetophenone as the only product with 80% yield within the time period of 38 min.
The bromination reaction of different substituted α-bromoketone was also performed, such as
2-hydroxy acetophenone gave the product α-bromo-2-hydroxy acetophenone with 87% yield
within 35 minutes. Bromination reaction of p-methoxy-acetophenone gave the product α-
bromo-p-methoxy-acetophenone with 89% yield in 30 min, higher yield is due to the electron
donating nature of methoxy group present in the para position of the benzene ring. Other
substituted ketones such as 4-methyl-2-hydroxy- acetophenone and 5-methyl-2-hydroxy-
acetophenone were also smoothly monobrominated to α-bromoketone in high yields with
85% with the time period of 40 minutes. Hence, the present approach is very simple and
efficient method for C-H bond functionalization reaction of many organic substrates and
provide an access to α-bromoketones.
3.6. The plausible mechanistic pathway
To explain the observed behaviour, a possible mechanism is shown in Fig 7. In the
first step vanadium(V) complexes react with hydrogen peroxide resulting in the formation of
peroxo-vanadium species. In the next step, the reaction of peroxo-vanadium with KBr yield
bromide species in the presence of an acid. In the last step, α-hydrogen abstraction by
monoperoxo vanadium(V) species occur giving rise to a reactive intermediate, which may
undergo nucleophilic displacement by the bromide anion yielding α-bromoketones as the
product.
Fig 7. Plausible mechanism for C-H bond functionalization catalysed by vanadium(V)
complexes
4. Conclusion

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Dioxido-vanadium(V) complexes containing mono hydrazone ligands were
synthesized in good yield. The complex was synthesized by reaction of the ligand with
vanadium pentoxide in 2:1 molar ratio in methanol. Single crystal suitable for Single XRD
analysis was obtained from DMF/water mixture in 2:3 (v/v) at room temperature within a
week. The complexes obtained adopted a square pyramidal geometry around vanadium ion
with slight distortion. The two vanadium(V) complexes can catalyse the peroxidative
bromination of organic substrates and can be considered as potential functional models of
vanadium halo-peroxidases and their application toward C-H bond functionalization.
Acknowledgements
Authors are thankful to, SAIF, North-Eastern Hill University, Shillong-793022, India
for providing NMR spectra. Sunshine D. Kurbah and I. Syiemlieh would like to thank UGC,
New Delhi for NFST fellowship. We are also thankful to computer center of the university,
for providing high performance computing facilities.
Supplementary data
Supplementary materials may be found online in the supporting information tab for this
article.
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Table 1. Crystal data and structure refinement for complexes 1 & 2
Complex 1
C34H42Br2N8O9V2
968.45
Complex 2
C15H18BrN4O5V
465.18
Empirical formula
Formula weight
Temperature/K
Crystal system
Space group
295.8(3)
monoclinic
P21/n
292.5(2)
triclinic
P-1
a/Å
b/Å
c/Å
α/°
β/°
γ/°
Volume/Å3
Z
8.3725(5)
15.0475(17)
32.227(3)
90
91.846(5)
90
8.1871(7)
11.2605(17)
11.4031(18)
105.961(14)
110.528(12)
96.387(10)
921.0(2)
4058.0(6)
4
2
ρcalcg/cm3
1.585
1.677
ꢀ/mm 1
2.491
1.677
Radiation
MoKα (λ = 0.71073)
7098/0/503
0.962
R1 = 0.0524, wR2 = 0.1363 R1 = 0.0570, wR2 = 0.1308
R1 = 0.0935, wR2 = 0.1657 R1 = 0.0809, wR2 = 0.1516
MoKα (λ = 0.71073)
3237/0/240
1.067
Data/restraints/parameters
Goodness-of-fit on F2
Final R indexes [I>=2σ (I)]
Final R indexes [all data]
Table 2. Bond Lengths and bond angles for complexes
Atom Atom Length/Å
V1
V1
V1
V1
V2
V2
V2
V2
V2
V1
O1
O2
O3
O4
O5
O6
O7
O8
N4
N1
1.891(3)
1.967(3)
1.661(3)
1.599(4)
1.980(3)
1.915(3)
1.660(3)
1.601(4)
2.165(4)
2.133(4)
Atom Atom Atom Angle/˚
O4
O3
O1
O3
O4
O4
O2
O3
V1
V1
V1
V1
V1
V1
V1
V1
O1
O1
O2
O2
O2
O3
N1
N1
105.19(18)
95.27(16)
146.58(16)
93.74(15)
102.78(16)
106.93(19)
74.20(14)
149.08(18)

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O1
O4
V1
V1
N1
N1
81.75(15)
103.52(17)

ACCEPTED MANUSCRIPT
Highlights
Dioxovanadium(V) complexes containing simple hydrazone ligands has been synthesized in
good yield.
The complexes were characterized by IR, UV-Visible and 1H NMR spectroscopies.
The structure of complexes has been established by Single Crystal X-ray crystallography.
The complexes act as catalyst which efficiently catalyzed C-H bond activation reaction.