Synthesis and Characterization of Ag@g?C3N4 and Its Photocatalytic Evolution in Visible Light Driven Synthesis Of Ynone

Article abstract of DOI:10.1002/cctc.201901802

The primary aim of this work is to synthesize photocatalyst to promote the synthesis of ynones. In this context, we synthesized AgNPs@g?C₃N₄ nanocomposite. The nanocomposite was characterized by using SEM, HR-TEM, XRD, EDS, ICP-AES,

Full text of DOI:10.1002/cctc.201901802

Accepted Article
Title: “Synthesis and Characterization of Ag@g-C3N4 and its
photocatalytic evolution in visible light driven synthesis of ynone’’
Authors: Dilip Virjibhai Vasava and Sunil Patel
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“Synthesis and Characterization of Ag@g-C3N4 and its photocatalytic evolution in
visible light driven synthesis of ynone’’
Sunil B. Patel[a] and Dilip V. Vasava*[b]
[38]
[39]
[40]
Abstract: The primary aim of this work is to synthesize photocatlyst to
promote the synthesis of ynones. In this context, we synthesized
AgNPs@g-C3N4 nanocomposite. The nanocomposite was
characterized by using SEM, HR-TEM, XRD, EDS, ICP-AES, Uv-Vis
DRS, XPS, PL and FT-IR. From the results of characterization, it was
transpired that the AgNPs anchored firmly on the carbon nitride sheet
and the size of nanoparticles ranges between 2-6 nm. We utilized the
photoactive nanocomposite for the synthesis of various substituted
ynones under visible light irradiation. Excellent yields were generated
for the various substituted ynones (74-84 %). Furthermore, we study
the gram scale synthesis and achieved yield up to 78 %. Recyclability
of the nanocomposite was also studied and found that the material
was recyclable up to 4 times without any significant loss in its activity.
We have used 80 W tungsten bulb (λ > 420 nm) as the light source
and GVL (gamma Valero lactone) as the solvent which proves the
, deboronative alkynylation
, Aza- Hanry reaction
,
[41]
dehalogenation reaction
, C-C and C-P bond formation
, intermolecular addition reaction[44]
,
[42]
[43]
reaction
, oxidation
Indole functionalization [45] , C-H functionalization [46] , heterocycle
synthesis & functionalization [47] and etc.
Ynones (α, β-acetylenic ketone), have numbers of application in
synthetic chemistry. They are involved in biologically active
components and utilized as vital building blocks in heterocycle
synthesis (Figure 1). The presence of carbonyl and the polarized
alkyne group makes ynones more reactive intermediate.[48]
Ynones are important intermediates for the construction of
process much greener as compared to the conventional methods.
heterocyclic compounds such as furan[49-50] , dihydropyranones
[51]
, pyroline[52] , pyrolle[53] , N- sulfinamines[54] , triazine[55]
,
,
Introduction
spyrobaciline[56] , pyrazoles[57-60] , oxazepines, and oxazines[61]
The environmental issues are drastically increasing day by day
and as a result, human facing major problems such as water, air,
soil adulteration because of major chemical industries. Due to that,
the natural resources affected rapidly and cause many serious
issues. So, to overcome such problems research efforts have
been made for cleaner and greener production by using
photocatalysis.[1-9] Photocatalysis is one of the widely studied
topics because of its wide range applicability. Many researchers
diazepines[62] , triazoles[63] , quinolones[64] and annulation.[65]
Various synthetic methods for the synthesis of ynones have been
reported by using various metals like magnesium[66] , silver[67]
cadmium[68] , silicon[69] , copper[70] , tin[71] , lithium[72] , gallium[73]
stibium[74] , indium[75] , zinc[76] and boron.[77]
,
,
In the recent years, polymeric graphitic carbon nitride (g-C3N4)
has gain more attention as a photocatalyst switching under visible
light irradiation. Because of the lower band gap of 2.7 eV, this
material has been extensively explored as an advanced modern
semiconductor for the photocatalytic applications.[78] Taking
have made the efforts to develop the sustainable catalytic
[10-15]
approaches for the cleaner production.
Several photo
catalytic protocols have been reported in the visible light
irradiation to reduce the water contamination like waste water
treatment [16], Dye degradation [17-21], degradation of organic
pollutants [22-26] , H2 production and CO2 reduction [2-4] Furthermore,
photocatalysis covers broad area of organic transformation such
inspiration
from
this,
we
synthesized
Ag@g-C3N4
nanocomposites for the catalytic application. We applied
synthesized nanocomposite for the catalytic evolution in cross-
coupling reaction between benzoyl chloride and phenylacetylene
in the presence of visible light irradiation (λ > 420 nm and intensity
[30-
as, cross-coupling reaction,[27-29] trifluoromethylation
31] ,decarboxylative coupling reaction [32-37] , cycloaddition reaction
11 candela).
[a]
Mr. S. B. Patel
School of Sciences, Department of chemistry, Gujarat University
Navrangpura Ahmedabad-380009.
E-mail: skpatel111812@gmail.com
[b]
Dr. D. V. Vasava
School of Sciences, Department of chemistry, Gujarat University
Navrangpura Ahmedabad-380009.
E-mail: dilipvasava20@gmail.com
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Figure 2. SEM image (a) g-C3N4 (a) and (b) AgNPs@g-C3N4.
Figure 1. Application of ynone in construction of various heterocycles and
annulation.
To evaluate the phase and crystal structure of the synthesized
nanocomposites, the prepared samples were analyzed by XRD.
In figure 3 the XRD pattern of g-C3N4 and AgNPs@g-C3N4 was
given. In the XRD pattern of g-C3N4 one broad peak at 27.4° 2
was observed and it was associated with (0 0 2) plane with d =
0.322 nm. The high and intense peak at 27.4° 2 was attributed
to the high interplanar stacking of the aryl re-arrangement which
referred as the (0 0 2) plane of g-C3N4 (ICCD card no 87-1526)
(Figure 3a). In Ag@g-C3N4 nanocomposite sample XRD shows
five different reflections including one peak of g-C3N4. The X-Ray
Diffraction peaks at 38.4°, 44.0°, 64.4° and 77.42° were referred
to (1 1 1), (2 0 0), (2 2 0) and (3 1 1) planes for silver nanoparticles
(Figure 3b). The observed pattern and reflection planes are in
good agreement with the standard pattern of AgNPs (ICCD card
no. 04-0783).[79] The peak intensity intended the low loading of
Ag+ ions on graphitic carbon nitride. In the second spectrum the
extra peaks except g-C3N4 confirmed the encapsulation of AgNPs
on g-C3N4. The average crystallite size of the AgNPs was
calculated by using Scherer’s formula. From the above discussed
results, we can say the AgNPs having face cantered cubic (fcc)
symmetry and having crystalline nature.
Results and Discussion
Photocatalysis is an important area of research in catalysis. The
g-C3N4 was having many properties of heterogeneous catalyst as
well as photocatalyst. Furthermore, it has high surface area,
stability and photo catalytic activity, and it has proved a very
interesting supporting material for photocatalysis. As a part of our
study we synthesized and characterized the catalyst by using
SEM, HR-TEM, EDX, XRD, Uv-Vis DRS, XPS, PL, FT-IR and ICP-
AES.
The morphology of synthesized samples was investigated though
SEM analysis. the SEM images of synthesized g-C3N4 and
AgNPs@g-C3N4 nanocomposite were given. The pure carbon
nitride reflects an aggregated particle which were larger in size.
On later investigation we observed the morphology of carbon
nitride was like flower petal. The layered surface of the
aggregation is smooth. After the encapsulation of silver
nanoparticles, the morphology did not affect but the surface was
seemed to be rough. Both the figures were given below which
(Figure 2a) indicates surface of carbon nitride before
퐾휆
퐷 =
β Cos ϴ
encapsulation and (Figure 2b) after encapsulation of AgNPs.
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Where D = average grain size; K = shape factor with a value of
∼0.9; λ = x-ray wavelength (Cu Kα = 0.15405 nm); β = (FWHM)
full width at half-maximum (in radians); and θ = Bragg’s angle.
The calculated average grain size of AgNPS@g-C3N4 were 4-8
nm.
Figure 3. X-ray diffraction pattern of g-C3N4 (a) and AgNPs@g-C3N4 (b).
To find out more information regarding the morphology, particle
size and shape of prepared sample AgNPs@g-C3N4 was
examined through TEM and HR-TEM analysis. As shown in
(Figure 4), the black coloured spots were referred to silver
nanoparticles and grey coloured area ascribed to surface of g-
C3N4. The synthesized material is capable to absorb visible light.
The grey surface in TEM image of g-C3N4 is capable to absorb
visible light. In figure it’s clearly seen that the interfacial contact of
silver nanoparticles with g-C3N4 sheet, which enclosed the whole
surface area of the sheet. From the figure we can concluded the
encapsulated AgNPs were spherical in shape and size as
measured between 2-6 nm. Furthermore, no agglomeration of
AgNPs were observed which is very good thing from the aspects
of heterogeneous catalysis. SAED pattern of nanocomposites
showed bright rings, specifying that the nanocomposite is highly
crystalline in nature. The bright fringes appeared were attributed
to (1 1 1), (2 0 0), (2 2 0) and (3 1 1) planes for metallic silver
species.
Figure 4. TEM images of AgNPs@g-C3N4 (a) at 0.2 um scale (b) at 100 nm
scale (c) at 50 nm scale (d) SAED pattern (e) HR-TEM image of AgNPs (f)
Particle size distribution curve.
For elemental information of the silver nanocomposites EDX
mapping of selected area was carried out. In (Figure 5) the peak
appeared near 0.3 and 3.0 keV confirmed the presence of silver
species in nanocomposites. In the mapping image different colour
appeared and they were attributed to different elements which
was further clarified in images where red colour was for silver. The
red coloured dots were very less in the image hence we
concluded that the loading of metal was very low in synthesized
nanocomposite. Furthermore, loading of silver was found 0.0531
mmol/gm from ICP-AES analysis.
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Typical FT-IR spectrum of silver nanocomposites was shown in
(Figure 6). As the material consist of triazine units the breathing
of triazine units can be seen at 796-808 cm-1. Here peaks
appeared at 1171 cm-1, 1438 cm-1 and 1671 cm-1 indicated the C-
N stretching of heterocycle and revelling the information about C-
N-C linkages[79] present in the material. Here we can see there
was no significant changes in the fresh nanocomposite and
nanocomposite after fourth cycle.
Figure 6. FT-IR images of (a) Fresh AgNPs@g-C3N4 and (b) Recycled
AgNPs@g-C3N4.
For the deeper investigation of elemental composition and
oxidation state of AgNPs@g-C3N4 XPS was carried out (Figure
7). The four elements (C, N, O, Ag) could be seen in the survey
spectrum of AgNPs@g-C3N4. The peak arise at 287.67 eV and
292.59 eV were denoted as C 1S peaks, which also revealing the
information about the sp2 hybridized carbon atoms and N-C-N
bonding in the g-C3N4. The peak arise at 399.18 eV was denoted
as N 1S peak, which significantly indicating the presence of sp3
hybridized N atoms and C-N-C linkages in the synthesized
material. [80,81] In the spectrum of Ag 3d the peaks arise at 367.18
eV and 373.16 eV can be denoted as Ag 3d5/2 and Ag 3d3/2. The
XPS results confirmed that the Ag nanoparticles firmly anchored
on the surface of g-C3N4.
Figure 5. EDX mapping image of AgNPs@g-C3N4.
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Figure 7. XPS spectra of Ag@g-C3N4 (a) XPS servey spectrum (b) High
resolution spectrum of C 1S (c) High resolution spectrum of N 1S (d) High
resolution spectrum of Ag 3d.
UV-Vis Diffuse Reflectance Spectra
To study the optical absorption ability of the synthesized samples,
the UV–vis DRS analysis was carried out. The spectral
measurements of pure g-C3N4 and Ag@g-C3N4 was carried out.
As shown in (Figure 8), the pure g-C3N4 existed good absorption
performance in the visible light region. The absorption edge of the
synthesized sample was estimated at about 450 nm, and the band
gap value was determined to be 2.72 eV for g-C3N4. For the
Ag@g-C3N4, the absorption capability was notably enhanced as
compared to the g-C3N4. In the spectra it was clearly seen that the
distinct red shift took place around 450-600 nm, which was took
place due to the SPR (silver surface plasmon resonance). The
results could elaborate that the optical absorption ability was
increased due to the Ag species. It was notable that the
absorption spectra of Ag@g-C3N4 are better than g-C3N4. The
enhanced optical absorption capability will upsurge the
photocatalytic activity. The UV-DRS measurement results proved
that the Ag played a crucial role to intensify the photocatalytic
activity of Ag@g-C3N4.[81]
Figure 8. (a) UV-Vis DRS spectra of g-C3N4 and 2% Ag@g-C3N4 , 3% Ag@g-
C3N4 (b) Band gap determination of g-C3N4 (c) SPR cherecteristics of Ag.
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To measure the separation capability and life time of
photogenerated carrier’s photoluminescence (PL) measurement
was used. Photoluminescence spectra of g-C3N4 and Ag@g-C3N4
were shown in figure 9. the excitation wavelength used is 325 nm
during the experiment. A strong peak was observed near 450 nm,
from the comparison of both the spectra, we observed the
photoluminescence intensity of g-C3N4 is relatively more than the
Ag@g-C3N4. The weaker peak intensity showed a slower
recombination rate of photogenerated carriers. On the other hand,
the presence of Ag NPs present at the surface of g-C3N4
effectively slower down the recombination rate of electrons and
hole pairs. This leads the e- and h+ to facilitates the photo catalytic
process of Ag@g-C3N4.[81]
model substrates. A 80 W tungsten filament blub was used as the
irradiation source (λ > 420 nm) scheme 1.
.
Scheme 1. Synthesis of ynone from benzoyl chloride and phenylacetylene.
Table 1. Screening of cross-coupling reaction between benzoyl
chloride and phenylacetylene under different conditions
Entry
Catalyst
Solvent
Base
Yield b
1
Ag@g-C3N4
Ethylene
glycol
Et3N
52 %
2
3
4
5
Ag@g-C3N4
Ag@g-C3N4
Ag@g-C3N4
Ag@g-C3N4
PEG-100
PEG-200
GVL
Et3N
Et3N
Et3N
Et3N
50 %
40 %
84 %
75 %
Figure 9. PL spectra of pure g-C3N4 and Ag@g-C3N4.
Propylene
carbonate
6
Au@g-C3N4
Cu@g-C3N4
Pd@g-C3N4
Ag@g-C3N4
Ag@g-C3N4
GVL
GVL
GVL
GVL
GVL
Et3N
64 %
69 %
65 %
10 %
14 %
7
Et3N
Light driven catalytic evolution of AgNPs@g-
C3N4 for the synthesis of ynone
8
Et3N
9
K2CO3
Na2CO3
10
11
After successfully characterizing the nanocomposite, we planned
to examine its catalytic efficacy in the cross-coupling reaction
between benzoyl chloride and terminal alkynes. As we discussed
earlier, our aim was to develop efficient and greener conditions
for the synthesis of ynones. We mainly focused on greener
reagents and reusability of material. For this, we chose the
reaction between benzoyl chloride and phenyl acetylene as the
Ag@g-C3N4
Ag@g-C3N4
GVL
GVL
Cs2CO3
Et3N
12 %
12 c
No reaction
a
Reaction conditions: Benzoyl chloride (1.1 mmol), phenylacetylene
(1.2mmol), Base (2 mmol), Catalyst (100 mg), Solvent (2 mL), under N2 atm.,
80 W tungsten blub, 24 h. GVL = gamma Valero lactone.
b Isolated yields, c in dark conditions.
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Here we were selected only greener solvents which were
available easily and unharmful for the environment. As a
prospectus to obtain benign conditions we scan the experiment in
ethylene glycol (EG), PEG-100, PEG-200, gamma Valero lactone
(GVL) and propylene carbonate. After scanning the solvents, we
found good results were obtained in gamma Valero lactone and
achieved yield up to 84 % table 1 (entry 1 to 5). Some other
nanocomposites were used such as Au@g-C3N4, Cu@g-C3N4
and Pd@g-C3N4 table 1 (entry 6, 7, 8) but best results were
obtained with the Ag@g-C3N4. Bases such as Et3N, K2CO3,
Na2CO3 and Cs2CO3 table 1 (entry 4, 9, 10, 11) were incorporated
in the reaction. Amongst them results obtained with Et3N were
optimum. In rest of the inorganic bases desired product was not
obtained in good yield the results have been mentioned in table 1.
Furthermore, the reaction carried out in absence of base, but the
reaction was not initiated. Hence, we concluded that the basic
medium was required to carry out the reaction. Similar results
were obtained while the reaction was carried out in absence of
nanocomposite and in absence of light.
a Table 2. AgNPs@g-C3N4 catalyzed cross coupling reaction between
Substituted benzoyl chloride and terminal alkynes
% Yield b
Entry
Reactant
Product
1
84
2
81
Hence by taking the optimized reaction conditions further
reactions were carried out. The scope of the reaction was further
generalized by using different substituted benzoyl chlorides and
terminal acetylenes. Better group tolerance was observed under
optimized photocatalytic conditions. We have used bicyclic
benzoyl chloride, -methoxy, -methyl and -chloro substituted
benzoyl chlorides all the substituted derivatives provided
excellent yield up to 70-84 % [table 2 (entry 1 to 8)].
Correspondingly, in substituted alkynes such as -Cl, -Br, -F, -CH3,
-OCH3 we were obtained excellent yield up to 80-84 % [table 2
(entry 9 to 13)]. However, in aliphatic alkynes the expected yield
was lower in the case of cyclopropyl acetylene 76 % yield was
obtained and in 1-hexyne yield was declined to 74 % [table 2
(entry 14, 15)]. Conclusion drawn from the obtained results that
the aromatic substituted benzoyl chloride and acetylene reacted
well to give corresponding ynones in excellent yield.
3
4
5
6
80
84
82
82
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7
15
80
74
a
Reaction conditions: Benzoyl chloride (1.1 mmol), phenylacetylene
(1.2mmol), Et3N (2 mmol), Catalyst (100 mg), GVL (2 mL), under N2 atm.,
80 W tungsten blub, 24 h. GVL = gamma Valero lactone.b Isolated yields.
8
9
79
84
Gram scale synthesis of ynone
Scale up synthesis is one of the important factors in
heterogeneous catalysis. We scanned synthesized nanomaterial
for the scale up synthesis by taking 5.0 gm of the initial reactant.
The reaction was stirred under visible light irradiation for 24 h
under optimized reaction condition and 3.90 gm of ynone (78%
yield) was obtained.
10
83
11
84
Scheme 2. Gram scale synthesis of ynone.
Photocatalytic Mechanism
The probable photocatalytic mechanism for the synthesis of
ynone is discussed based on SPR effect of Ag species and
decreased rate of the recombination of photogenerated e- and h+
pairs. Modification of g-C3N4 with silver nanoparticles increased
the photocatalytic performance of Ag@g-C3N4. When Ag@g-C3N4
irradiated to visible light source (80 W tungsten bulb, λ > 420 nm),
the e- and h+ pairs are separated, e- is excited and moved to CB
of g-C3N4 while on the other hand, h+ stay at VB of g-C3N4. Then
e- transfers to Ag nanoparticles due to the high Schottky barrier.
[81] Finally, transfer takes place to the surface of photocatalyst to
join the formation of silver acetylide complex with terminal
acetylene in presence of base and reaction facilitates towards the
formation of ynone.
12
80
13
80
14
76
Recyclability Study
Recyclability is an important factor which affects the performance
of the heterogeneous nanomaterial. So, we carried out the
recyclability studies of the synthesized nanocomposite. In that
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context, the recovered catalyst obtained after first cycle were
washed thrice with absolute alcohol and dried prior to reuse. We
repeated the same procedure for 4 times, after the fourth cycle,
the activity of nanocomposite gradually reduces. So, we conclude
that we can use the nanocomposite at least 4 times without any
significant loss in its catalytic activity (Figure 10). Furhtermore, we
investigate the resone behind the reduced activity after fourth
cycle. We found that the loss of catalyst during the recovery
process may be responsible for the decreasing activity of the
catalyst.
Figure 10. Recyclability image of AgNPs@g-C3N4.
Post recyclability studies were also carried out to ensure the
stability of the catalyst. TEM, XRD and XPS analysis were carried
out to ensure the stability of catalyst under optimized reaction
conditions. TEM, XRD and XPS analysis were given in (Figure
11), from the results we can concluded that there was no notable
changes observed in the catalyst after the reaction.
Figure 11. Post reaction XRD, TEM and XPS of AgNPs@g-C3N4.
Conclusions
In conclusion, AgNPs@g-C3N4 has been developed and
characterized by sophisticated techniques such as, SEM, HR-
TEM, EDX, XRD, ICP-AES, XPS, Uv-Vis DRS, PL and FT-IR. In
TEM and HR-TEM analysis results we found the size of the
AgNPs were in nano dimension (2-6 nm) and were highly
crystalline in nature. Similar evidences were found in XRD
analysis. Loading of metal was found very low (0.0531 mmol/gm)
from ICP-AES analysis. After successfully characterization of
nanocomposite, we have explored the photocatalytic activity of
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AgNPs@g-C3N4. We have developed greener pathway for the
access of various substituted ynones under visible light irradiation
(λ > 420 nm). Furthermore, we have utilized only greener solvents
which were environmentally friendly.
Conflict of interest
The authors declared no conflict of interest.
Keywords: Green approach • Heterogeneous catalysis • Silver
nanocomposite • Visible light • ynone
Experimental Section
Materials
All chemicals were used of analytical grade and of the highest purity
available. Benzoyl chloride, and terminal acetylenes were purchased from
Sigma-Aldrich. Ethyl acetate, ethanol, hexane and NaBH4 were purchased
from TCI. Water used in all experiments was purified by Millipore-Q system.
All glassware was thoroughly washed with aqua regia.
Synthesis of carbon nitride (g-C3N4)
Synthesis of carbon nitride was done according to the literature. [80]
Preparation of Ag@g-C3N4 nanocomposite
Ag@g-C3N4 nanocomposite was synthesized by a sorption reduction
method. Firstly, prepared solution of 1.0 mmol AgSO4 in deionized water
with 2 gm of carbon nitride powder was added in the solution with
continuous stirring. After 1 h the Ag+ ions were reduced by passing cold
NaBH4 solution at 10 °C. Excess of reagents were removed by washing
with deionized water and finally washed with ethanol. Resultant
nanocomposite was dried in oven at 60 °C for 10 h.
General procedure for the synthesis of ynone
Take 1.1 mmol of benzoyl chloride and 1.2 mmol of Phenylacetylene in10
mL RBF add 100 mg of Ag@g-C3N4 nanocomposite and 2 mL solvent.
Stirred the reaction mixture at room temperature and add appropriate
amount of Et3N (2 mmol), further the reaction mixture was purged with N2
and put the reaction mixture under visible light irradiation source (80 W
tungsten bulb, λ > 420 nm) with continuous stirring. Check the progress of
reaction by TLC (hexane/ethyl acetate 9:1), after 24 h the reaction was
completed. After completion of the reaction, quenched the reaction mixture
in ice water and extracted with ether. Wash the ether layer with brine
solution and dried over anhydrous MgSO4. The solvent was removed
under reduce pressure to get the desired crude product. The crude product
was further purified by column chromatography (hexane/ethyl acetate
100:1), and analyzed by 1H NMR and 13C NMR.
Acknowledgements
The authors are grateful to, MNIT, Jaipur for SEM, HR-TEM, XRD,
XPS, PL and EDX analysis, SAIF, Punjab University, Chandigarh,
for the 1H-NMR and 13C-NMR analysis. Authors are also grateful
to, Department of physics, school of sciences, gujarat university
for Uv-Vis DRS analysis specially Dr. U. S. Joshi and his research
students Poornima Sengunthar, Nisha Thangachen and Shivangi
patel.
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[1]
[2]
.
X. Lang, X. Chen, J. Zhao, Chem. Soc. Rev. 2014, 43, 473-486.
Y. Huo, J. Zhang, K. Dai, Q. Li, J. Lv, G. Zhu, C. Liang, App. Catal.
B: Env. 2019, 241, 528-538.
T. Hu, Z. Li, L. Lu, K. Dai, J. Zhang, R. Li, C. Liang, J. Coll. Int. Sci.
2019, 555, 166-173.
T. Hu, K. Dai, J. Zhang, G. Zhu, C. Liang, Appl. Surf. Sci. 2019, 481,
1385-1393.
F. Mei, J. Zhang, K. Dai, G. Zhu, C. Liang, Dalton Trans. 2019, 48,
1067-1074
Y. Huo, Y. Yang, K. Dai, J. Zhang, Appl. Surf. Sci. 2019, 481, 1260-
1269.
N. Zhang, Y. Zhang, M. Q. Yang, Y. J. Xu, Curr. Org. Chem. 2013, 17,
2503-2515.
M. Q. Yang, Y. J. Xu, Phys. Chem. Chem. Phys. 2013, 15, 19102-
19118.
[40] A. G. Condie., J. C. González-Gómez., C. R. Stephenson. J. Am.
Chem. Soc. 2010, 132, 1464-1465.
[41] T. Maji, A. Karmakar, O. Reiser, J. Org. Chem. 2010, 76, 736-739.
[42] D. P. Hari, B. Kꢀnig, Org. Lett. 2011, 13, 3852-3855.
[43] M. Rueping, R. M. Koenigs, K. Poscharny, D. C. Fabry, D. Leonori, C.
Vila, Chem.–A Eur. J. 2012, 18, 5170-5174.
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[44] R. S. Andrews, J. J. Becker, M. R. Gagné, Angew. Chem. Int. Ed.
2010, 49, 7274-7276.
[45] A. A. Festa, L. G. Voskressensky, E. V. Van der Eycken, Chemical
Society Reviews. 2019. Visible light-mediated chemistry of indoles
and related heterocycles. DOI: 10.1039/c8cs00790j
[46] M. Uygur, O. G. Mancheño, Org. & Bio. Chem. 2019, 17, 5475-5489.
[47] J. R. Chen, X. Q. Hu, L. Q. Lu, W. J. Xiao, Acc. Chem. Res. 2016, 49,
1911-1923.
[48] R. E. Whittaker, A. Dermenci, G. Dong, Synthesis, 2016, 48, 161-183.
[49] H. Sheng, S. Lin, Y. Huang, Tetrahedron Lett. 1986, 27, 4893-4894.
[50] A. V. Kel'i, V. Gevorgyan, J. Org. Chem. 2002, 67, 95-98.
[51] S. L. Shi, M. Kanai, M. Shibasaki, Angew. Chem. Int. Ed. 2012, 51,
3932-3935.
C. Han, Z. R. Tang, J. Liu, S. Jin, Y. J. Xu, Chem. Sci. 2019, 10, 3514-
3522.
[10] C. Han, S. H. Li, Z. R. Tang, Y. J. Xu, Chem. Sci. 2018, 9, 8914-8922.
[11]
[12]
[13]
[14]
[15]
[16]
Y. Zhang, N. Zhang, Z. R. Tang, Y. J. Xu, Chem. Sci. 2012, 3, 2812-
2822.
N. Zhang, M. Q. Yang, S. Liu, Y. Sun, Y. J. Xu, Chem. Rev. 2015, 115,
10307-10377.
F. Mei, K. Dai, J. Zhang, W. Li, C. Liang, Appl. Surf. Sci. 2019, 488,
151-160.
Z. Li, X. Wang, J. Zhang, C. Liang, L. Lu, K. Dai, Chin. J. Catal. 2019,
40, 326-334.
Y. Huo, Z. Wang, J. Zhang, C. Liang, K. Dai, Appl. Surf. Sci. 2018,
459, 271-280.
S. Dong, J. Feng, M. Fan, Y. Pi, L. Hu, X. Han, J. Sun, RSC. Adv.
2015, 5, 14610-14630.
[52] N. Gouault, M. Le Roch, C. Cornee, M. David, P. Uriac, J. Org.
Chem. 2009, 74, 5614-5617.
[53] Z. Wang, Y. Shi, X. Luo, D. M. Han, W. P. Deng, N. J. Chem. 2013, 37,
1742-1745.
[54] Y. Liu, T. R. Kang, Q. Z. Liu, L. M. Chen, Y. C. Wang, J. Liu, Y. M. Xie,
J. L. Yang, L. He, Org. Lett. 2013, 15, 6090-6093.
[55] S. Hwang., H. Bae., S. Kim., S. Kim. Tetrahedron, 2012, 68, 1460-
1465.
[56] W. P. Unsworth, J. D. Cuthbertson, R. J. Taylor, Org. Lett. 2013,
15, 3306-3309.
[57] M. Kandasamy, B. Ganesan, M. Y. Hung, W. Y. Lin, Eur. J. Org.
Chem. 2019, 20, 3183-3189.
[17]
[18]
M. Yin, Z. Li, J. Kou, Z. Zou, Env. Sci. & tech. 2009, 43, 8361-8366.
S. W. Cao, Z. Yin, J. Barber, F. Y. Boey, S. C. J. Loo, C. Xue, ACS
app.mater. & inter. 2011, 4, 418-423.
[58] R. E. Whittaker, A. Dermenci, G. Dong, Synthesis, 2016, 48, 161-183.
[59] M. Schuler, F. Silva, C. Bobbio, A. Tessier, V. Gouverneur, Angew.
Chem. Int. Ed. 2008, 47, 7927-7930.
[19]
[20]
[21]
P. Wang. B. Huang, X. Qin, X. Zhang, Y. Dai, J. Wei, M. H. Whangbo.
Angew. Chem. Int. Ed. 2008, 47, 7931-7933.
A. K. L. Sajjad, S. Shamaila, B. Tian, F. Chen, J. Zhang. J. Hazardous
Mat. 2010, 177, 781-791.
A. T. Kuvarega, R. W. Krause, B. B. Mamba. J. Phy. Chem. C. 2011,
115, 22110-22120.
[60] J. D. Kirkham, S. J. Edeson, S. Stokes, J. P. Harrity, Org. Lett. 2012,
14, 5354-5357.
[61] C. François-Endelmond, T. Carlin, P. Thuery, O. Loreau, F. Taran,
Org. Lett. 2009, 12, 40-42.
[62] S. G. Huang, H. F. Mao, S. F. Zhou, J. P. Zou, W.
Zhang, Tetrahedron Lett. 2013, 54, 6178-6180.
[22]
[23]
J. Tang, Z. Zou, J. Ye. Angew. Chem. Int. Ed. 2004, 43, 4463-4466.
R. Abe, H. Takami, N. Murakami, B. Ohtani. J. Am. Chem. Soci. 2008,
130, 7780-7781.
[63] N. Li, D. Wang, J. Li, W. Shi, C. Li, B. Chen, Tetrahedron Lett. 2011,
52, 980-982.
[64] O. Seppaenen, M. Muuronen, J. Helaja, Eur. J. Org. Chem 2014, 19,
4044-4052.
[65] Z. Lian, M. Shi, Eur. J. Org. Chem, 2012, 581.
[66] J. W. Kroeger, J. A. Nieuwland, J. Am. Chem. Soc. 1936, 58, 1861-
1863.
[24] D. Chatterjee, S. Dasgupta. J. Photochem. and Photobio. C: 2005, 6,
186-205.
[25] D. Lu, H. Wang, X. Zhao, K. K. Kondamareddy, J. Ding, C. Li, P. Fang,
ACS Sus. Chem. & Eng. 2017, 5, 1436-1445.
[26] C. Yu, G. Li, S. Kumar, K. Yang, R. Jin. Adv. Mater. 2014, 26, 892-898.
[27] S. Kim, J. Rojas-Martin, F. D. Toste, Chemical science 2016, 7, 85-88.
[28] S. Protti, M. Fagnoni, A. Albini. Angew. Chem. Int. Ed. 2005, 44, 5675-
5678.
[29] M. De Carolis, S. Protti, M. Fagnoni, A. Albini, Angew. Chem. Int. Ed.
2005, 44, 1232-1236.
[67] R. B. Davis, D. H. Scheiber, J. Am. Chem. Soc. 1956, 78, 1675-1678.
[68] O. G. Yashina, T. V. Zarva, T. D. Kaigorodova, L. I. Vereshchagin,
J. Org. Chem. 1968, 4, 2104–2107.
[69] D. R. M. Walton, F. J. Waugh, Organomet. Chem. 1972, 37, 45.
[70] MW. Logue, G. L. Moore, J. Org. Chem. 1975, 40, 131– 132.
[71] MW. Logue, K. Teng, J. Org. Chem. 1982, 47, 2549–2553.
[72] HC. Brown, US. Racherla, SM. Singh, Tetrahedron Lett. 1984, 25,
2411–2414.
[30] W. Fu, W. Guo, G. Zou, C. Xu, J. Fluorine Chem. 2012, 140, 88-94.
[31]
[32]
Y. Ye, M. S. Sanford, J. Am. Chem. Soc. 2012, 134, 9034-9037.
F. Le Vaillant, T. Courant, J. Waser, Angew. Chem. Int. Ed. 2015, 54,
11200-11204.
[73] Y. Han, L. Fang, WT. Tao, YZ. Huang, Tetrahedron Lett. 1995, 36,
1287–1290.
[33]
[34]
[35]
C. Yang, J. D. Yang, Y. H. Li, X. Li, J. P. Cheng, J. Org. Chem. 2016,
81, 12357-12363.
J. Yang, J. Zhang, L. Qi, C. Hu, Y. Chen, Chem. Commun. 2015, 51,
5275-5278.
T. Qin, L. R. Malins, J. T. Edwards, R. R. Merchant, A. J. Novak, J. Z.
Zhong, P. S. Baran, Angew. Chem. Int. Ed. 2017, 56, 260-265.
[74] N. Kakusawa, K. Yamaguchi, J. Kurita, T. Tsuchiya, Tetrahedron Lett.
2000, 41, 4143–4146.
[75] I. Pérez, JP. Sestelo, LA. Sarandeses, J. Am. Chem. Soc. 2011, 123,
4155–4160.
[76] KY. Lee, MJ. Lee, JN. Kim, Tetrahedron. 2005, 61, 8705–8710.
[36] Q. Q. Zhou, W. Guo, W. Ding, X. Wu, X. Chen, L. Q. Lu, W. J. Xiao,
Angew. Chem. Int. Ed. 2015, 54, 11196-11199.
[77] Y. Nishihara, D. Saito, E. Inoue, Y. Okada, M. Miyazaki, Y. Inoue,
Tetrahedron Lett. 2010, 51, 306–308.
[37] J. Liu, Q. Liu, H. Yi, C. Qin, R. Bai, X. Qi, A. Lei, Angew. Chem. Int. Ed.
2014, 53, 502-506.
[78] L. Ge, C. Han, J. Liu, Journal of Materials Chemistry, 2012, 22, 11843-
11850.
[38] Z. Lu, M. Shen, T. P. Yoon, J. Am. Chem. Soc. 2011, 133, 1162-1164.
[39] H. Huang, G. Zhang, L. Gong, S. Zhang, Y. Chen, J. Am. Chem. Soc.
2014, 136, 2280-2283.
[79] S. B. Patel, D. V. Vasava, ChemistrySelect 2018, 3, 471-480.
[80] D. Liu, Y. Liu, P. Huang, C. Zhu, Z. Kang, J. Shu, M. Chen, X. Zhu, J.
Guo, L. Zhuge, X. Bu, P. Feng, T. Wu, Angew. Chem. Int.l Ed. 2018, 57,
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[81]
K. Qi, Y. Li, Y. Xie, S. Y. Liu, K. Zheng, Z. Chen, Z., R. Wang, Front.
chem., 2019, 7, 1-9..
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We have developed silver nanocomposite mediated synthesis of various substituted ynones in the presence of visible light. We have
utilized the GVL as a greener solvent for the reaction. The use of 80 W tungsten bulb as a visible light source and heterogeneous
catalyst makes the process sustainable.
This article is protected by copyright. All rights reserved.