Photo-induced thiol coupling and C-H activation using nanocrystalline lead-halide perovskite catalysts

Article abstract of DOI:10.1039/c8cy01240g

The use of photon energy to promote chemical transformations offers versatile control of reaction kinetics and progress. Over the past decade, many photoactive transition-metal complexes and organic chromophores were developed to catalyze chemical transformations, enabling a myriad of reactions and compounds that were previously inaccessible via traditional synthetic methods. Here, we demonstrate the photocatalytic oxidative coupling of organic thiols using cesium lead halide perovskite nanocrystals as photocatalysts. The photo-catalyzed thiol coupling reactions selectively produced symmetric and unsymmetrical disulfides in high yields (68-96% isolated yields). Additionally, we discovered a perovskite-catalyzed phosphonylation of tertiary amines via visible-light-mediated cross-dehydrogenative coupling reaction, and obtained good isolated yields (50-96%). The variety of visible-light-induced photocatalytic processes that perovskite nanocrystals are capable of, coupled with their facile preparation, easily tunable redox potentials, high catalytic efficiency and reusability, presents great opportunities for their future applications in green and sustainable organic synthesis.

Full text of DOI:10.1039/c8cy01240g

View Article Online
View Journal
Catalysis
Science &
Technology
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: W. Wu, Y. Wong,
Z. Tan and J. Wu, Catal. Sci. Technol., 2018, DOI: 10.1039/C8CY01240G.
This is an Accepted Manuscript, which has been through the
Volume 6 Number 1 7 January 2016 Pages 1–308
Royal Society of Chemistry peer review process and has been
accepted for publication.
Catalysis
Science &
Technology
Accepted Manuscripts are published online shortly after
www.rsc.org/catalysis
acceptance, before technical editing, formatting and proof reading.
Using this free service, authors can make their results available
to the community, in citable form, before we publish the edited
article. We will replace this Accepted Manuscript with the edited
and formatted Advance Article as soon as it is available.
You can find more information about Accepted Manuscripts in the
author guidelines.
Please note that technical editing may introduce minor changes
to the text and/or graphics, which may alter content. The journal’s
ISSN 2044-4753
standard Terms & Conditions and the ethical guidelines, outlined
in our author and reviewer resource centre, still apply. In no
event shall the Royal Society of Chemistry be held responsible
PAPER
Qingzhu Zhang et al.
Catalytic mechanism of C–F bond cleavage: insights from QM/MM
analysis of fluoroacetate dehalogenase
for any errors or omissions in this Accepted Manuscript or any
consequences arising from the use of any information it contains.
rsc.li/catalysis

Please do not adjust margins
Catalysis Science & Technology
Page 1 of 7
View Article Online
DOI: 10.1039/C8CY01240G
Journal Name
ARTICLE
Photo-Induced Thiol Coupling and C−H Activation Using
Nanocrystalline Lead-Halide Perovskite Catalysts
Wen-Bin Wu,a‡ Ying-Chieh Wong,a‡ Zhi-Kuang Tan,*ab Jie Wu*a
Received 00th January 20xx,
Accepted 00th January 20xx
The use of photon energy to promote chemical transformations offers versatile control of reaction kinetics and progress.
Over the past decade, many photoactive transition-metal complexes and organic chromophores were developed to
catalyze chemical transformations, enabling a myriad of reactions and compounds that were previously inaccessible via
traditional synthetic methods. Here, we demonstrate the photocatalytic oxidative coupling of organic thiols using cesium
lead halide perovskite nanocrystals as photocatalysts. The photo-catalyzed thiol coupling reactions selectively produced
symmetric and unsymmetrical disulfides in high yields (68-96% isolated yields). Additionally, we discovered a perovskite-
catalyzed phosphonylation of tertiary amines via visible-light-mediated cross-dehydrogenative coupling reaction, and
obtained good isolated yields (50-96%). The variety of visible-light-induced photocatalytic processes that perovskite
nanocrystals are capable of, coupled with their facile preparation, easily tunable redox potentials, high catalytic efficiency
and reusability, presents great opportunities for their future applications in green and sustainable organic synthesis.
DOI: 10.1039/x0xx00000x
www.rsc.org/
high efficiency.7 The Xu and Xiao group discovered that Ni-modified
CdS nanoparticles could efficiently catalyze an aerobic oxidation of
alcohols to aldehydes and ketones.8 Very recently, the Weix group
1. Introduction
Visible-light-mediated photochemistry has witnessed dramatic
developments over the past ten years.1-6 Because most organic
substrates do not absorb photons in the visible-light region, using
visible-light rather than strong UV light to promote organic
demonstrated that the CdSe QDs could serve as an advantageous
replacement for Ru- or Ir-based photoredox catalysts with
improved turnover numbers.9 Furthermore, the König group has
described that the appropriate combination of heterogeneous
semiconductors with chiral organocatalysts could promote highly
stereoselective transformations under visible-light-irradiation.10
However, development of semiconductors as photocatalysts for
organic bond formation is still at its early stage,7-21 and there
transformations often delivers
a cleaner and more selective
reaction. More importantly, by activation with visible-light, the
photocatalyst can function as a single-electron redox mediator or
facilitate energy transfer to activate a diverse range of organic
substrates, which enables previously inaccessible transformations
and products. In this context, transition-metal chromophores such
as Ru and Ir polypyridyl complexes have garnered particular
recognition due to their rich redox chemistry at the MLCT (metal-to-
ligand charge-transfer) excited states.4 On the other hand, organic
photocatalysts enable unique chemistry far more than just “metal-
free” alternatives to transition-metal photocatalysts.1 Among other
possible photocatalysts, inorganic semiconductors, such as
quantum dots (QDs) and TiO2, offer a unique way to harvest light
energy and activate organic molecules through electron-hole-
transfer. Notably, in 2014, the Wu group reported the use of CdSe
QDs as the photocatalyst to achieve an oxidant-free
dehydrogenative coupling of thiols to symmetric disulfides in very
remains
a critical need for the development of effective
heterogeneous photocatalysts to enable valuable and sustainable
synthetic processes.
Lead halide perovskites, such as CsPbX3 and CH3NH3PbX3 (X
represents I, Br or Cl, Fig. 1a), exhibit exceptional semiconductor
properties,22-24 and have been leveraged in various optoelectronic
applications such as photovoltaics25-30 and light-emitting devices.31-
36
Compared to other semiconductors, perovskites offer easy
materials preparation and application via low-temperature
solution-based methods, and allow facile tuning of their
semiconductor bandgap through the control of their halide
compositions. Fig. 1a shows the unit cell crystal structure of
perovskites and their electronic bandgaps. A change in the halide
content from iodide to bromide to chloride allows the bandgap to
be tailored from 1.8 eV to 3.0 eV, as estimated from the absorbance
and photoluminescence (PL) spectra of the respective perovskites in
Fig. 1b. Perovskites, being direct-bandgap semiconductors, possess
high extinction coefficient, and depending on their halide content,
could allow light absorption over a wide UV to near infrared range.
Hence, we envision that the solution-dispersible nanocrystals (NC)
of CsPbX3 perovskites,37 which exhibit high photo-activity and large
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 1
Please do not adjust margins

Please do not adjust margins
Catalysis Science & Technology
Page 2 of 7
View Article Online
DOI: 10.1039/C8CY01240G
ARTICLE
Journal Name
surface area, will be a promising class of photocatalysts.38 To the using a 1 mol% CsPbBr3 perovskite catalyst (entry 1). No external
best of our knowledge, there has been no reports on the use of lead oxidant was required, as a significant amount of product 2a was
halide perovskites as photocatalysts to synthesize useful organic generated under strict oxygen-free environment (entry 2), with
molecules. We herein
molecular hydrogen produced as the reduction by-product (Fig.
Table 1 Condition optimization for CsPbBr3 perovskite catalyzed
disulfide formationa
b
CsPbI
3
CsPbBr
CsPbCl
3
3
White LED
S11a, see ESI†). However, the transformation was even more
efficient without special deoxygenation treatment (entry 1 vs. 2),
enabling a convenient operation protocol. CH2Cl2 was the most
effective solvent among those tested (entries 3, 4 and 6). A mixed
solvent system CH2Cl2/cyclohexane (1:1, v/v) afforded an equally
good yield to that with CH2Cl2 alone (entry 7). Bulk perovskites
(entries 8-9) were shown to exhibit much lower catalytic activity,
indicating that the reactions occurred on the large surface areas
offered by the nanocrystals. Crucially, the absence of either the
catalyst or light (entry 10) gave negligible reaction yields,
confirming the photocatalytic nature of the reaction. The computed
external quantum yield of this thiol coupling was 3.6%, which is
reasonably high compared to other semiconductor-catalyzed non-
400
500
600
700
800
Wavelength (nm)
Fig 1. (a) Unit cell structure and energy level diagram of CsPbX3
perovskites. Energy levels were estimated from literature values,39-
40 and converted to redox potentials vs. SCE (-4.68 eV vs. vacuum).
(b) Absorbance (dashed lines) and photoluminescence (solid lines)
spectra of perovskites.
report that CsPbX3 perovskites can effectively activate S−H and C−H
bonds
under
visible-light-irradiation
for
subsequent
transformations.
radical chain-based photo chemical transformations (e.g.,
alkylation using CdSe QD as the catalyst).9
β-
2. Results and Discussion
The photocatalytic activity of perovskite nanocrystals with
different halide contents was subsequently tested. As shown in
Table 2, the bromide-rich perovskites gave the highest reaction
yields (entries 2 and 3). The smallest-bandgap iodide perovskite
offered a lower yield of 58% (entry 1) due to its lower oxidative
potential compared to CsPbBr3. The reaction was significantly less
active for the larger-bandgap chloride-rich perovskites (entries 5-6),
and this is due to the material’s low extinction coefficient in the
visible range, hence causing lower photoexcitation efficiency by
white LEDs (Fig. 1b). However, photoexcitation with a 400 nm UV
LED allows a high reaction yield (93%) to be obtained using CsPbCl3
catalyst (entry 7). In addition, an in-situ halide exchange using
CsPbCl3 with bromine,48 can also trigger this reaction and turn
CsPbCl3 into an effective photocatalyst under visible-light (entries 8-
9). TEM and HR-TEM images (Fig. 2) have also shown the perovskite
cuboidal nanocrystalline structure and size distribution to be
preserved at the end of an 8-hour reaction, hence suggesting that
the catalyst was robust and reusable. The reusability of the catalyst
was investigated in CH2Cl2/cyclohexane mixed solvent under white
2.1 CsPbX3 catalyzed oxidative coupling of thiols to disulfides
Disulfides are essential for proteins to fold into biologically active
conformations,41-42 and were also widely applied in fine chemical
industry as anti-oxidants, pharmaceuticals, pesticides, and as
vulcanization agents.43 Symmetric disulfides are normally accessed
by oxidative coupling of thiols with oxidants, which normally suffer
from at least one drawback such as over-oxidation, high catalyst-
loading, excess and expensive oxidants, strong acidic or basic media,
and high temperature.44 The development of
a mild, green,
selective, and efficient thiol coupling protocol is still highly desired.
In this context, photocatalysis offers a milder pathway to achieve
this important transformation.7, 45-47
Our investigation commenced with using thiophenol 1a as the
substrate and a broadband white light-emitting diode (LED, 420 nm
to 700 nm emission, Fig. 1b) as light source to investigate the effect
of various parameters on the photo-coupling reaction. As shown in
Table 1, we discovered that thiophenol 1a can be successfully
coupled to disulfide 2a in virtually quantitative yield in CH2Cl2 by
2 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Please do not adjust margins
Catalysis Science & Technology
Page 3 of 7
View Article Online
DOI: 10.1039/C8CY01240G
Journal Name
ARTICLE
LED irradiation for consecutive three batches of thiophenol except the sterically demanding substrate tert-butyl mercaptan 1i
coupling, achieving 98%, 95%, and 90% NMR yield respectively (Fig. which showed a less efficient transformation (82% conversion).
S9a, see ESI†), which indicated
nanocrystalline perovskite catalyst.
a good reusability of the
Table 2 Reaction investigation using CsPbX3 perovskite catalysts
with different halogen contentsa
Table 3 Substrate scope of symmetric and unsymmetrical disulfides
formationa
CsPbBr3 (1 mol%)
S
R2
R1 SH
R2 SH
+
SH
R1
S
CsPbX3 perovskite (1 mol%)
S
CH2Cl2, white LEDs, rt, air, 6 h
CH2Cl2, white LEDs, rt, air, 12 h
2 X
1
1'
2a-l
S
2a 2i
-
: R1 = R2
1a
2a
: R1 = Ar, R2 = Alkyl
2j 2l
-
Yield of 2a (%)b
F
Entry
CsPbX3 perovskite
S
S
S
S
S
1
2
3
4
CsPbI3
CsPbBr3
58
98
98
68
S
F
2a, 95%
2b, 91%
2c, 92%
CsPbBr2Cl
CsPbBr1.5Cl1.5
OMe
N
S
N
S
S
S
S
S
5
CsPbBrCl2
CsPbCl3
CsPbCl3
35
12
93
S
S
6
MeO
7c
2d
2e
2f
, 90%
, 93%
, 86%
8
9
CsPbCl3 + Br2
Br2
62
8
S
S
S
S
S
S
a Reaction conditions: thiophenol (1a, 0.2 mmol), CsPbX3 (1 mol%),
and CH2Cl2 (4 mL) at room temperature for 6 h. b NMR yields with
1,3,5-trimethoxybenzene as the internal standard. c Irradiated using
UV LED strip (maximum emission at 400 nm).
2g, 90%
2h, 96%
2i, 76%
N
S
N
S
S
N
S
S
S
S
S
b
b
b
2j
, 71%
2k
2l
, 68%
, 72%
c
(2j: 2a = 6: 1)c
(
:
> 20: 1)
c
70% conversion
no Ar-S-S-Ar byproduct
2k 2e
a
1a i
Standard reaction conditions: thiols ( - , 0.2 mmol), CsPbBr3 (1 mol%), and CH2Cl2 (4
mL) at room temperature under white LED for 12 h. Average isolated yields of two runs.
b
c
1a 1e
1l 2h
, 0.2 mmol), Alkyl-SH (
2i
and , 0.3 mmol). Ratios and
Ar-SH (
,
and
conversions based the crude 1H NMR spectra.
We further tested the formation of unsymmetrical disulfides, as
they are important bioactive compounds, with some showing
promise in clinical evaluation for tumor treatment.49-50 As illustrated
in Table 3, by mixing one equivalent of an aryl thiol and 1.5
equivalent of an aliphatic thiol in the presence of the perovskite
nanocrystal catalyst under visible-light-irradiation, unsymmetrical
aryl alkyl disulfides 2j to 2l were produced in high selectivity (more
than statistical 3:1 ratio of hetero- to homo-disulfides). A time-scale
study (Fig. S1, see ESI†) indicated that the better selectivity may
originate from the fact that the aryl thiyl radicals generated are
more reactive than alkyl thiyl radicals, and the aryl-aryl disulfide
intermediate can react with alkyl thiyl radicals to generate the
desired unsymmetrical alkyl aryl sulfide, while the slowly generated
dialkyl sulfide cannot.51 This photocatalytic protocol provides a mild
way to selectively prepare certain types of unsymmetrical disulfides
in an atom- and step-economic way.
Fig. 2 TEM images of CsPbBr3 NCs before and after reaction. (a)
CsPbBr3 NCs, (b) 1 mol% CsPbBr3 NCs with PhSH in CH2Cl2 under
white LEDs irradiation for 8 h, (c) HR-TEM image of CsPbBr3 NCs, (d)
HR-TEM image of 1 mol% CsPbBr3 NCs with PhSH in CH2Cl2 under
white LEDs irradiation for 8 h.
In order to elucidate the reaction mechanisms, we measured the
PL intensity of CsPbBr3 and CsPbI3 perovskites with different added
concentrations of thiophenol, as shown in Fig. 3a and 3b. An
unexpected enhancement in the PL of CsPbBr3 and CsPbI3 was
observed upon the addition of thiophenol. Such behavior deviates
markedly from typical photocatalytic reactions where both
electron-transfer and energy-transfer processes from the
photocatalyst to the substrates lead to PL quenching. The PL
enhancement observations here could be rationalized by the
The optimized photocatalytic protocol was then applied to
convert a broad range of thiols into their corresponding disulfides
(Table 3). The couplings were quite efficient with aromatic
substrates, no matter with electron-rich, electron-poor, or
heterocyclic aryl substituents
(2a-2e). Aliphatic thiols can be
converted into the disulfides in excellent yields as well (2f-2h),
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 3
Please do not adjust margins

Please do not adjust margins
Catalysis Science & Technology
Page 4 of 7
View Article Online
DOI: 10.1039/C8CY01240G
ARTICLE
Journal Name
coordination of the thiol group to the nanocrystal surface at Pb-rich perovskite photocatalysts for organic synthesis, we show that the
defective sites, thereby passivating the surface and shutting off cesium lead perovskite nanocrystals can be effectively applied for
non-radiative Shockley-Read-Hall recombination. The binding of C−H activation by evaluating the phosphonylation of N-aryl
thiols to the Pb atoms on the surface of perovskites has also been tetrahydroisoquinoline derivatives and simple tertiary amines (for
confirmed by a characteristic Pb−S bond peak around 800 cm-1 in optimization, see ESI†, Table S1).56-58 As shown in Table 4, by the
the FTIR spectra (Fig. S13, see ESI†).52 Our observations suggest that employment of 1 mol% of CsPbBr3 in toluene under white LED
the efficacy of a photocatalytic reaction may not necessarily be irradiation, a range of phosphite esters
inferred via PL quenching, as typically described by the Stern- N-phenyl tetrahydrosioquinoline to deliver phosphonylation
Volmer relationship, since adventitious factors such as defect products 5a 5d in good to excellent yields. Both electron-rich and
passivation could completely mask and overpower any charge electron-deficient substituents on the N-aryl or the isoquinoline ring
transfer quenching effects. retained the high reactivity 5e 5k). Notably, the perovskite
4 can undergo the CDC with
-
(
-
Based on the accumulated experimental evidence, we propose photocatalysis strategy could be applied to more challenging simple
plausible mechanisms for the thiol coupling in Fig. S15 (See ESI†). acyclic and cyclic tertiary amines to produce
a
First, the thiol S and H coordinates to Pb and Br respectively. Upon
photo-excitation, the electron in the perovskite conduction band
PhSH Conc.
transfers to the proton while the hole in the valence band transfers
CsPbBr3
0 M
to the mercaptan group, leading to the formation of a hydrogen
radical and a thiyl radical (see ESI† for the experimental support
towards generation of thiyl radicals). The former will couple to
produce H2 while the thiyl radicals couple to form the
corresponding disulfides on the surface of the catalyst. In the
presence of air, O2 can be reduced by accepting electrons in the
0.017 M
0.051 M
0.068 M
0.085 M
-
-
conduction band of CsPbBr3 to give superoxide (O2 ꢀ) (Ered [O2/ O2 ꢀ]
= -0.8 V vs. SCE], which may promote the thiol coupling.
During our experiments, we discovered that the absorbance
edge of the perovskite nanocrystals blue-shifted monotonically
from 530 nm to 440 nm over the course of the reaction, as shown in
Fig. S12 (See ESI†). Such spectral shifts are reminiscent of bandgap
changes due to halide exchange reactions, which is well-reported
for lead halide perovskites mixed with other ionic halide sources.37,
480
500
520
540
560
580
Wavelength (nm)
b
PhSH Conc.
53-54
CsPbI3
In our case, this spectral shift is a result of a slow photo-
0 M
0.017 M
0.034 M
0.051 M
0.068 M
activated halide exchange of the bromide perovskites with the
CH2Cl2 solvent, which indicated a perovskite-promoted C−Cl bond
cleavage. The photo-promoted anion exchange between CsPbBr3
with CH2Cl2 has been confirmed by XRD study of the perovskite
nanocrystals before and after reaction, as well as the detection of
bromochloromethane of the reaction product mixture. We
conducted the experiments in the dark and confirmed that there
were no spectral shifts in the perovskite, indicating that this halide
exchange reaction with dichloromethane was photo-activated.
Spectral shifts were also observed when experiments were
conducted in the absence of thiophenol, hence showing that the
halide exchange was independent of the thiol-coupling process.
Detailed study on the mechanism, scope evaluation, and its
application to access full-spectral tuning of perovskite
photoluminescence from red to violet will be reported in another
report.
620
640
660
680
700
720
740
760
780
Wavelength (nm)
Fig. 3 PL intensity of (a) CsPbBr3 in THF and (b) CsPbI3 in CH2Cl2 with
different added concentrations of thiophenol.
the corresponding C−P coupling product (5l and 5m) in moderate
efficiency. On the other hand, N-methylmorpholine cannot give the
desired product (5n). Similar to thiol coupling, the phosphonylation
proceeded under strict air-free environment with evolution of
molecular hydrogen gas (Fig. S11b, see ESI†), however, it became
more efficient without any special degassing treatment. Finally, we
examined the recyclability and reusability of the CsPbBr3 perovskite
for this phosphonylation. It was found that the catalyst could be
reused at least five times without a noticeable loss of catalytic
activity (Fig. S10, see ESI†).
2.2 Perovskite catalyzed dehydrogenative C−P coupling reactions
of tertiary amines with phosphite esters
The direct use of C−H bonds for cross-coupling reactions is a
primary goal for green organic synthesis due to its atom- and step-
economy. The cross-dehydrogenative coupling (CDC) reaction of the
C−H bond adjacent to an amino nitrogen atom represents an
important synthetic strategy as the nitrogen-containing
pharmaceutical compounds presented
a substantial level of
structural complexity.55 To further demonstrate the utility of
4 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Please do not adjust margins
Catalysis Science & Technology
Page 5 of 7
View Article Online
DOI: 10.1039/C8CY01240G
Journal Name
ARTICLE
The luminescence quenching study showed that both the remarkable potential lies in the materials’ large extinction
tetrahydroisoquinoline and phosphite would enhance the PL of coefficients, broad absorption spectra, facile bandgap tuning, rich
CsPbBr3 at low concentration (Fig. S14, see ESI†), indicating the surface chemistry, and easy fabrication. We have demonstrated a
coordination of both substrates to the perovskite nanocrystal clean, mild, and efficient oxidative coupling of thiols to symmetric
surface. However, PL quenching of CsPbBr3 was observed when disulfides with or without external oxidants, and further extended
further increasing the amount of tetrahydroisoquinoline or the protocol to prepare valuable unsymmetrical disulfides. The
phosphite, with
tetrahydrosioquinoline, which may suggest an electron-transfer dehydrogenative coupling between tertiary amines and phosphite
between the photocatalyst and the substrates. plausible esters further illustrates that the perovskite nanocrystals can
a
higher quenching rate associated with subsequent discovery of
a
visible-light-mediated cross-
A
mechanism was thus proposed for the perovskite-catalyzed activate a variety of organic substrate patterns, and offer an initial
phosphonylation (Fig. S16, see ESI†). Upon irradiation by visible- blueprint towards its utilization in a diverse range of photo-
light, the electron in the perovskite conduction band transfers to catalyzed organic transformations. The easy fabrication of
-
molecular O2 to form superoxide radical anion O2 ꢀ, while the hole in perovskite nanocrystals also indicates their potential applications in
the valence band transfers to the amine substrate on the catalyst
continuous-flow synthesis, and these studies are ongoing in our
laboratories.
Table
4 Substrate scope of cross-dehydrogenative coupling
between tertiary amines and phosphite estersa,b
Conflicts of interest
The authors declare no competing financial interest.
R1
N
O
R1
Ar
N
R3O
R3O
Ar
P
O
CsPbBr3 (1 mol%)
or
R3O
P H
+
or
toluene, white LEDs, air, rt, 4 h
OR3
Acknowledgements
N
N
OPh
OPh
The authors are grateful for the financial support provided by
the National University of Singapore (R-143-000-665-114, R-
143-000-696-114, and R-143-000-674-114) and A*STAR
RIE2020 AME (R-143-000-690-305).
P
O
3
4
5
(1.1 equiv.)
N
N
O
N
N
O
PhO
PhO
EtO
P
iPrO
P
BnO
BnO
P
P
EtO
O
iPrO
O
5a, 96%
5b, 70%
5c, 78%
5d, 70%
Notes and references
§
Photoluminescence.
Abbreviations: SCE, Saturated calomel electrode; PL,
N
N
N
N
PhO
PhO
PhO
PhO
PhO
PhO
PhO
P
P
P
P
O
F
O
Br
O
OMe
PhO
O
1
2
3
4
5
6
7
N. A. Romero and D. A. Nicewicz, Chem. Rev., 2016, 116
10075-10166.
D. Ravelli, S. Protti and M. Fagnoni, Chem. Rev., 2016, 116
9850-9913.
K. L. Skubi, T. R. Blum and T. P. Yoon, Chem. Rev., 2016, 116
10035-10074.
C. K. Prier, D. A. Rankic and D. W. C. MacMillan, Chem. Rev.,
2013, 113, 5322-5363.
J. Xuan and W.-J. Xiao, Angew. Chem. Int. Ed., 2012, 51
6828-6838.
J. M. R. Narayanam and C. R. J. Stephenson, Chem. Soc. Rev.,
2011, 40, 102-113.
X.-B. Li, Z.-J. Li, Y.-J. Gao, Q.-Y. Meng, S. Yu, R. G. Weiss, C.-H.
Tung and L.-Z. Wu, Angew. Chem. Int. Ed., 2014, 53, 2085-
2089.
,
,
,
5g
, 82%
5e
, 82%
5f
, 88%
5h
, 59%
Cl
O
N
N
O
N
Br
O
PhO
PhO
PhO
PhO
PhO
P
P
P
O
PhO
O
5k, 86%c
5i
5j
, 63%
, 70%
O
,
N
N
O
OPh
OPh
OPh
P
P
N
P
O
OPh
OPh
O
OPh
d
d
e
5l
, 50%
5m
, 61%
5n
, n.r.
a Standard reaction conditions: 3 (0.1 mmol), 4 (0.12 mmol, 1.1 equiv), CsPbBr3 (1 mol%), and toluene
(1.5 mL) at room temperature under white LED for 4 h. b Average isolated yields of two runs. c THF as
solvent. d CsPbBr3 (5 mol%), THF as solvent. e No reaction.
8
9
Z. Chai, T.-T. Zeng, Q. Li, L.-Q. Lu, W.-J. Xiao and D. Xu, J. Am.
Chem. Soc., 2016, 138, 10128-10131.
J. A. Caputo, L. C. Frenette, N. Zhao, K. L. Sowers, T. D. Krauss
and D. J. Weix, J. Am. Chem. Soc., 2017, 139, 4250-4253.
surface to generate a radical cation intermediate. The active species
-
O2 ꢀ subsequently abstracts a proton from the radical cation
intermediate to form an
α-amino radical, which will be further 10 M. Cherevatskaya, M. Neumann, S. Füldner, C. Harlander, S.
Kümmel, S. Dankesreiter, A. Pfitzner, K. Zeitler and B. König,
Angew. Chem. Int. Ed., 2012, 51, 4062-4066.
11 Z. Zhang, K. Edme, S. Lian and E. A. Weiss, J. Am. Chem. Soc.,
2017, 139, 4246-4249.
oxidized to an imine cation. The deprotonated phosphite
nucleophiles will attack the imine cation to yield the final coupling
product.
12 L.-M. Zhao, Q.-Y. Meng, X.-B. Fan, C. Ye, X.-B. Li, B. Chen, V.
Ramamurthy, C.-H. Tung and L.-Z. Wu, Angew. Chem. Int.
Ed., 2017, 56, 3020-3024.
13 S. C. Jensen, S. B. Homan and E. A. Weiss, J. Am. Chem. Soc.,
2016, 138, 1591-1600.
3. Conclusions
Our study has demonstrated the potential of using perovskite
semiconductors as photocatalysts in organic synthesis. Their
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 5
Please do not adjust margins

Please do not adjust margins
Catalysis Science & Technology
Page 6 of 7
View Article Online
DOI: 10.1039/C8CY01240G
ARTICLE
Journal Name
14 C. M. Bernt, P. T. Burks, A. W. DeMartino, A. E. Pierri, E. S. 39 P. Schulz, E. Edri, S. Kirmayer, G. Hodes, D. Cahen and A.
Kahn, Energy Environ. Sci., 2014, 7, 1377-1381.
40 K. T. Butler, J. M. Frost and A. Walsh, Mater. Horiz., 2015, 2,
Levy, D. F. Zigler and P. C. Ford, J. Am. Chem. Soc., 2014, 136
2192-2195.
,
15 B. I. Ipe and C. M. Niemeyer, Angew. Chem. Int. Ed., 2006,
45, 504-507.
16 D. C. Fabry, Y. A. Ho, R. Zapf, W. Tremel, M. Panthofer, M.
Rueping and T. H. Rehm, Green Chem., 2017, 19, 1911-1918.
17 S. P. Pitre, T. P. Yoon and J. C. Scaiano, Chem. Commun.,
2017, 53, 4335-4338.
228-231.
41 V. T. Maulik, S. L. Jennifer and J. S. Teruna, Curr. Protein Pept.
Sci., 2009, 10, 614-625.
42 B. Heras, M. Kurz, S. R. Shouldice and J. L. Martin, Curr. Opin.
Struct. Biol., 2007, 17, 691-698.
43 R. J. Cremlyn, An Introduction to Organosulfur Chemistry,
Wiley-VCH, New York, 1996.
44 D. Witt, Synthesis, 2008, 2491-2509.
18 C. D. McTiernan, X. Leblanc and J. C. Scaiano, ACS Catal.,
2017,
7, 2171-2175.
19 C. Bottecchia, N. Erdmann, P. M. A. Tijssen, L.-G. Milroy, L. 45 H. J. Kim, J. H. Yoon and S. Yoon, J. Phys. Chem. A, 2010, 114
,
Brunsveld, V. Hessel and T. Noël, ChemSusChem, 2016,
1781-1785.
20 C. Vila and M. Rueping, Green Chem., 2013, 15, 2056-2059.
9,
12010-12015.
46 M. Oba, K. Tanaka, K. Nishiyama and W. Ando, J. Org. Chem.,
2011, 76, 4173-4177.
21 L. Cermenati, A. Albini, L. Cermenati, C. Richter and A. Albini, 47 A. Talla, B. Driessen, N. J. W. Straathof, L.-G. Milroy, L.
Chem. Commun., 1998, 805-806.
Brunsveld, V. Hessel and T. Noël, Adv. Synth. Catal., 2015,
357, 2180-2186.
48 D. Solis-Ibarra, I. C. Smith and H. I. Karunadasa, Chem. Sci.,
22 G. Xing, N. Mathews, S. Sun, S. S. Lim, Y. M. Lam, M. Grätzel,
S. Mhaisalkar and T. C. Sum, Science, 2013, 342, 344-347.
23 S. D. Stranks, G. E. Eperon, G. Grancini, C. Menelaou, M. J. P.
2015, 6, 4054-4059.
Alcocer, T. Leijtens, L. M. Herz, A. Petrozza and H. J. Snaith, 49 R. K. Ramanathan, J. Abbruzzese, T. Dragovich, L. Kirkpatrick,
Science, 2013, 342, 341-344.
24 Y. Chen, M. He, J. Peng, Y. Sun and Z. Liang, Adv. Sci., 2016,
1500392.
25 A. Kojima, K. Teshima, Y. Shirai and T. Miyasaka, J. Am. Chem.
Soc., 2009, 131, 6050-6051.
26 M. M. Lee, J. Teuscher, T. Miyasaka, T. N. Murakami and H. J.
Snaith, Science, 2012, 338, 643-647.
27 J. Burschka, N. Pellet, S.-J. Moon, R. Humphry-Baker, P. Gao, 52 Z. Liu, Y. Bekenstein, X. Ye, S. C. Nguyen, J. Swabeck, D.
J. M. Guillen, A. F. Baker, L. A. Pestano, S. Green and D. D.
Von Hoff, Cancer Chemother. Pharmacol., 2011, 67, 503-509.
50 R. K. Ramanathan, D. L. Kirkpatrick, C. P. Belani, D. Friedland,
S. B. Green, H.-H. S. Chow, C. A. Cordova, S. P. Stratton, E. R.
Sharlow, A. Baker and T. Dragovich, Clin. Cancer Res., 2007,
13, 2109-2114.
3,
51 J. Yuan, C. Liu and A. Lei, Org. Chem. Front., 2015, 2, 677-680.
M. K. Nazeeruddin and M. Gratzel, Nature, 2013, 499, 316- Zhang, S.-T. Lee, P. Yang, W. Ma and A. P. Alivisatos, J. Am.
319. Chem. Soc., 2017, 139, 5309-5312.
28 H.-S. Kim, C.-R. Lee, J.-H. Im, K.-B. Lee, T. Moehl, A. 53 D. M. Jang, K. Park, D. H. Kim, J. Park, F. Shojaei, H. S. Kang,
Marchioro, S.-J. Moon, R. Humphry-Baker, J.-H. Yum, J. E.
Moser, M. Grätzel and N.-G. Park, Sci. Rep., 2012, , 591.
29 N. J. Jeon, J. H. Noh, Y. C. Kim, W. S. Yang, S. Ryu and S. I. 54 G. Nedelcu, L. Protesescu, S. Yakunin, M. I. Bodnarchuk, M. J.
J.-P. Ahn, J. W. Lee and J. K. Song, Nano Lett., 2015, 15, 5191-
5199.
2
Seok, Nat. Mater., 2014, 13, 897-903.
30 W. Wang, M. O. Tade and Z. Shao, Chem. Soc. Rev., 2015, 44
5371-5408.
Grotevent and M. V. Kovalenko, Nano Lett., 2015, 15, 5635-
5640.
55 L. Shi and W. Xia, Chem. Soc. Rev., 2012, 41, 7687-7697.
,
31 Z. K. Tan, R. S. Moghaddam, M. L. Lai, P. Docampo, R. Higler, 56 X.-Z. Wang, Q.-Y. Meng, J.-J. Zhong, X.-W. Gao, T. Lei, L.-M.
Zhao, Z.-J. Li, B. Chen, C.-H. Tung and L.-Z. Wu, Chem.
Commun., 2015, 51, 11256-11259.
F. Deschler, M. Price, A. Sadhanala, L. M. Pazos, D.
Credgington, F. Hanusch, T. Bein, H. J. Snaith and R. H.
Friend, Nat. Nanotechnol., 2014,
32 H. Cho, S.-H. Jeong, M.-H. Park, Y.-H. Kim, C. Wolf, C.-L. Lee,
9
, 687-692.
57 W.-J. Yoo and S. Kobayashi, Green Chem., 2014, 16, 2438-
2442.
J. H. Heo, A. Sadhanala, N. Myoung, S. Yoo, S. H. Im, R. H. 58 M. Rueping, S. Zhu and R. M. Koenigs, Chem. Commun.,
Friend and T.-W. Lee, Science, 2015, 350, 1222-1225.
33 N. Wang, L. Cheng, R. Ge, S. Zhang, Y. Miao, W. Zou, C. Yi, Y.
Sun, Y. Cao, R. Yang, Y. Wei, Q. Guo, Y. Ke, M. Yu, Y. Jin, Y.
Liu, Q. Ding, D. Di, L. Yang, G. Xing, H. Tian, C. Jin, F. Gao, R.
2011, 47, 8679-8681.
H. Friend, J. Wang and W. Huang, Nat. Photon., 2016, 10
699-704.
,
34 M. Yuan, L. N. Quan, R. Comin, G. Walters, R. Sabatini, O.
Voznyy, S. Hoogland, Y. Zhao, E. M. Beauregard, P.
Kanjanaboos, Z. Lu, D. H. Kim and E. H. Sargent, Nat. Nano,
2016, 11, 872-877.
35 Q. A. Akkerman, V. D’Innocenzo, S. Accornero, A. Scarpellini,
A. Petrozza, M. Prato and L. Manna, J. Am. Chem. Soc., 2015,
137, 10276-10281.
36 G. Li, F. W. R. Rivarola, N. J. L. K. Davis, S. Bai, T. C. Jellicoe, F.
de la Peña, S. Hou, C. Ducati, F. Gao, R. H. Friend, N. C.
Greenham and Z.-K. Tan, Adv. Mater., 2016, 28, 3528-3534.
37 L. Protesescu, S. Yakunin, M. I. Bodnarchuk, F. Krieg, R.
Caputo, C. H. Hendon, R. X. Yang, A. Walsh and M. V.
Kovalenko, Nano Lett., 2015, 15, 3692-3696.
38 H. Huang, H. Yuan, K. P. F. Janssen, G. Solís-Fernández, Y.
Wang, C. Y. X. Tan, D. Jonckheere, E. Debroye, J. Long, J.
Hendrix, J. Hofkens, J. A. Steele and M. B. J. Roeffaers, ACS
Energy Lett., 2018, 3, 755–759.
6 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Page 7 of 7
Catalysis Science & Technology
View Article Online
DOI: 10.1039/C8CY01240G
R1SH
R1S-SR1
R1S-SR2
+
R2SH
OR'
P OR'
N
N
H
R
O
R
Cesium lead halide perovskite nanocrystals have been the first time utilized as photocatalysts for organic
bond formations.