Visible-light-induced denitrogenative phosphorylation of benzotriazinones: A metal- And additive-free method for accessing: Ortho -phosphorylated benzamide derivatives

Article abstract of DOI:10.1039/d0gc03613g

Metal-free, visible-light-induced denitrogenative phosphorylation of 1,2,3-benzotriazinones was achieved. With the use of eosin Y as a photoredox catalyst, N,N-diisopropylethylamine as a base, CH3CN-H2O as a solvent and sunlight or a blue LED as a light source, a variety of aryl-phosphonates, aryl-phosphinates, and aryl-phosphine oxides were efficiently prepared. In addition, B2pin2 instead of P-nucleophiles as a radical acceptor was also demonstrated. The key advantages of this newly developed method are the clean reaction profile, use of a low-cost organic-dye catalyst, energy efficiency, broad substrate scope, good to excellent yields and large-scale synthetic applicability. The gram-scale synthesised compounds could be isolated in pure form just upon extraction, followed by re-crystallisation; no tedious chromatographic purification was required.

Full text of DOI:10.1039/d0gc03613g

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DOI: 10.1039/D0GC03613G
ARTICLE
Visible-light-induced denitrogenative phosphorylation of
benzotriazinones: a metal- and additive-free method for
accessing ortho-phosphorylated benzamide derivatives
Received 00th January 20xx,
Accepted 00th January 20xx
Fushan Chen, Shanshan Hu, Sipei Li, Guo Tang,* and Yufen Zhao
DOI: 10.1039/x0xx00000x
Metal-free, visible-light-induced denitrogenative phosphorylation of 1,2,3-benzotriazinones was achieved. With
the use of eosin Y as a photoredox catalyst, N,N-diisopropylethylamine as a base, CH3CN-H2O as a solvent and
sunlight or blue LED as a light source, a variety of aryl-phosphonates, -phosphinates, and -phosphine oxides
were efficiently prepared. In addition, B2pin2 instead of P-nucleophiles as a radical acceptor was also
demonstrated. The key advantages of this newly developed method are the clean reaction profile, use of low-
cost organic-dye catalyst, energy-efficiency, broad substrate scope, good to excellent yields and large-scale
synthetic applicability. The gram-scale synthesised compounds could be isolated pure just upon extraction,
followed by re-crystallisation; no tedious chromatographic purification was required.
A. Ni(0)-catalyzed denitrogenative transannulation
Introduction
O
O
R
Ni(cod)2/L
R1 R2
O
R
N
Organophosphorus compounds are widely utilised in the fields of
pharmaceutical1, functional material2 and agricultural chemistry,3
particularly aromatic phosphorus compounds act as useful ligands in
transition-metal-catalysed reactions.4 Consequently considerable
attention has been paid to the study of aryl-P bonds formation and
various strategies for the synthesis of these scaffolds have been
established over the past few decades. Pioneered by Hirao,5 the
transition-metal-catalysed phosphorylation of different aryl
precursors such as arylhalides, aryl boronic acids, aryl mesylates,
triarylbismuths, arylnitriles, aryl sulfides, arylsilanes and
aroylhydrazides with phosphorus-based nucleophiles has seen an
explosion of interest.6 Although remarkable achievements have been
made in this field, high reaction temperature as well as long reaction
time are still needed.
R
N
N
N
Ni
R2
N2
R2
N
R1
N
R1
B. fac-Ir(ppy)3-hv-promoted denitrogenative transannulation
O
O
Ar
Ar1
fac-Ir(ppy)3
Ar
+
Ar1
N
N
H
rt, blue LEDs
N
C. Ni(0)-catalyzed denitrogenative ortho-functionalization
O
Ar
OH
R
O
O
N
Ni(cod)2/L
O
H
R
Ar
N
N
Ar
or
+
N
H
OH
or
N
B
OH
D. Pd/Cu catalyzed denitrogenative ortho-alkynylation
O
O
Ar
R
Over the past several years, transition-metal-triggered
denitrogenative annulation of 1,2,3-benzotriazin-4(3H)-ones with
Pd(OAc)2/L
CuCN
Ar
N
H
+
R
N
N
H
N
various -compounds provided an applicable route to heterocyclic
skeletons (Scheme 1A).7 This synthetic strategy has aroused great
attention due to the use of benzotriazinones as a versatile and
important building block, which can be easily prepared from
commercially available methyl anthranilate. Besides, nitrogen is the
only byproduct in the reactions. Recently, Yu et al. discovered an
iridium-polypyridyl complex catalysed denitrogenative alkyne
insertion of 1,2,3-benzotriazinones for the preparation of
isoquinolones via a radical mechanism (Scheme 1B).8 Apart from
E. Organic-dye-catalyzed denitrogenative ortho-phosphorylation
this work
(
)
R1
R2
O
O
or
P
O
R1
P
R
N
N
R
+
Ar
N
Eosin Y (5 mol %)
rt, Ar, DIPEA (2 equiv)
OR3
R2
Ar
H
N
MeCN (2.0 mL)-H2O (0.3 mL)
Eosin Y as a catalyst
Blue LED or sunlight
Aryl-phosphonates and -phosphine oxides
Metal- and additive-free
Room temperature
Scheme 1. Denitrogenative reactions of benzotriazinones.
Department of Chemistry, College of Chemistry and Chemical Engineering, and
the Key Laboratory for Chemical Biology of Fujian Province, Xiamen University,
Xiamen, Fujian 361005, China. E-mail: t12g21@xmu.edu.cn
Electronic Supplementary Information (ESI) available: Experimental procedures for
the synthesis, spectral data and NMR spectra of compounds 3a-3y, 4a-4d, 4f-4i,
6a and 6b. See DOI: 10.1039/x0xx00000x
cyclisation products, nickel-catalysed ortho-alkenylated, -arylated
and -alkylketoned benzamides were successfully synthesised from
benzotriazinones by the research groups of Mannathan,9a Cheng9b and
Li (Scheme 1C).9c The Mannathan group also reported an efficient
palladium-catalyzed ortho-alkynylation reaction of 1,2,3-
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benzotriazinones with aromatic terminal alkynes (Scheme 1D).7g Table 1. Optimisation of the reaction conditionsa
View Article Online
DOI: 10.1039/D0GC03613G
Although the use of transition-metal catalysts in the synthesis of fine
chemicals and pharmaceutical intermediates has become common in
the last few decades, the use of transition metals often entails
additional procedures to reduce the content of the residual metals and
improve the quality of pharmaceutical ingredients.10
O
EtO
O
DIPEA (2 equiv)
PC (5 mol %)
P
O
Ph
EtO
N
N
Ph
P(OEt)3
+
N
Solvent, rt, 90 min
Blue LEDs (30 W)
H
N
2a
1a
3a
Entry
1
2
Photocatalyst
Fluorescein
Rhodamine B
Rhodamine 6G
Eosin Y
Solvent (mL)
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
MeCN
Yield(%)b
Photoredox catalysis has emerged as a powerful and reliable tool
for the construction of C–C and C–heteroatom bonds because of its
sustainable and economy friendly characteristics. Myriad elegant
works of visible-light-induced reaction have been well documented
for years.11 From the environmental and economic points of view,
organic-dye is an attractive alternative to expensive and multi-step
prepared iridium and ruthenium polypyridyl complexes.12 Thus,
metal-free photocatalytic system has been documented as a promising
approach for modern organic synthesis. However, arylation of
phosphorus reagents via a single-electron-transfer (SET) process
under environment-friendly and metal-free conditions are relatively
scarce.13 Given our ongoing efforts to the exploration of green
methods of C–P bond construction,14 herein, we report the convenient
and efficient tactic for the synthesis of aromatic phosphorus via
organic-dye-catalysed denitrogenative phosphorylation of 1,2,3-
benzotriazin-4-(3H)-ones under the irradiation of blue light or
sunlight without any metal catalysts or additives (Scheme 1E).
48
40
7
3
4
54
42
32
58
49
<33
85
93(91)d
85
90
0
5
Eosin B
6
Na2Eosin Y
Eosin Y
7
8
Eosin Y
H2O
Solventc
9
Eosin Y
10
11
12
13e
14f
15g
16
Eosin Y
MeCN/H2O(0.1 mL)
MeCN/H2O(0.3 mL)
MeCN/H2O(0.5 mL)
MeCN/H2O(0.3 mL)
MeCN/H2O(0.3 mL)
MeCN/H2O(0.3 mL)
MeCN/H2O(0.3 mL)
Eosin Y
Eosin Y
Eosin Y (sunlight)
Eosin Y (dark)
Eosin Y
0
-
0
aReaction conditions: the reaction were performed with mixtures of 1a (0.2
mmol), 2a (0.3 mmol), base (0.4 mmol) and the photocatalyst (5 mol%) in the
solvent (2.0 mL) at room temperature under irradiation by blue LEDs (30 W)
for 90 min. bYield of 3a, determined by 31 P NMR analysis of the crude reaction
mixture using nC8H17P(O) (: 48 ppm) as an internal standard. cSolvent: DCE,
DMF, THF, acetone, EtOH were used. dValue in parentheses indicates the
isolated yield. eThe reaction worked with sunlight (25-30 oC). fThe reaction was
carried out at 60 oC in the darkness. gWithout DIPEA.
Results and discussion
A preliminary optimization of the reaction conditions was carried out
with 1,2,3-benzotriazinone 1a and triethyl phosphite 2a as the model
substrates (Table 1).
A mixture of both compounds, N,N-
diisopropylethylamine (DIPEA) and a photocatalyst was irradiated
with LEDs under an argon atmosphere. To our delight, in the presence
of fluorescein as a photocatalyst, the reaction in DMSO was irradiated
by blue LEDs, affording the desired product 3a in 48% yield (entry
1). Encouraged by this result, other cheap and readily available
organic dyes such as rhodamine B, rhodamine 6G, eosin Y, eosin B
and Na2eosin Y were next examined (entries 2-6), and eosin Y
delivered 3a in a yield of 54% (entry 4). In order to further improve
the efficiency of the reaction, many solvents instead of DMSO were
investigated, 3a was obtained in a similar yield when the reaction was
performed in MeCN or water (entries 7 and 8), and other solvents such
as DCE, DMF, THF, acetone and EtOH did not provide satisfactory
results (entry 9). Pleasingly, the targeted product 3a was detected in
85% yield in the mixed solvent of MeCN (2 mL) and H2O (0.1 mL)
at room temperature for 90 min (entry 10). The amount of H2O seemed
to significantly affect the reaction (entries 7–10). Furthermore, a 93%
yield was achieved with the mixed solvent of MeCN (2 mL) and H2O
(0.3 mL) application (entry 11). Further increasing the amount of H2O
to 0.5 mL, however, resulted in 3a with a slightly lower yield (entry
12). From an environmental and practical point of view, we were
intrigued to use abundant sunlight for activating this chemical
transformation. To our delight, the reaction under sunlight could
complete within 6 h with a yield of 90% (entry 13). The reaction didn’t
With the optimal reaction conditions identified, the scope of this
visible-light-catalysed denitrogenative ring-opening of 1,2,3-
benzotriazin-4-(3H)-ones for the synthesis of ortho-phosphorylated
aryl amide derivatives was investigated (Table 2). It was found that
1,2,3-benzotriazin-4-(3H)-one substrates possessing various
functional groups, such as alkyl, halogens, trifluoromethyl, ester,
ether and thioether at different positions on the benzene ring 1 could
be employed in this reaction, readily affording the respective products
in good to excellent yields (74-91%). Besides, substrates with a
multisubstituted benzene ring 1 were also well tolerated (3n-3o).
Notably, N-napthyl , N-pyridyl and N-styrenyl substrates proceeded
smoothly in the system to give corresponding phosphorylated
products 3p-3s in moderate yields (74-82%). Subsequently, we turned
our attention to explore the scope of substituents on the benzene ring
2. As expected, both electron-deficient groups (such as –CO2Me, -Cl
and -Br) and electron-rich groups (such as -Me and -OMe) on the
benzene ring 2 did not disturb the efficiency of this transformation and
the expected products (3t-3x) were isolated in yields range from 81 to
87%. Significantly, the reaction proceeds well in the presence of a
reactive furan ring, leading to the thiophene-derived phosphonate 3y
in 87% yield. Unfortunately, substrates bearing an aliphatic chain
instead of aryl group at the nitrogen atom were unreactive under
standard conditions and can be almost fully recovered probably due
to the unstable of radical anion intermediate formed during the
reaction (3z and 3aa). Those results clearly revealed that an aryl group
at the nitrogen atom was necessary to stabilise the key intermediate
and the electronic and steric factor of the aryl groups had a negligible
effect on the coupling reactivity. Furthermore, sunlight as a light
o
work without light even at 60 C (entry 14). Control experiments
without DIPEA or catalyst gave no desired product at all (entries 15
and 16).
2 | J. Name., 2012, 00, 1-3
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ARTICLE
phosphine oxides (4g-4i), which are important precursors to
DOI: 10.1039/D0GC03613G
triarylphosphine ligands, could be prepared in high yields under the
source could also effectively promote the reaction. When the reaction
tube was put on the window sill under sunlight for 6 hours without
stirring, the reaction mixture became turbid, indicating an ongoing
reaction and affording corresponding phosphorylated products 3a-3x
in satisfied yields.
View Article Online
4
optimal conditions. Furthermore, the reactions could also be
conducted by using sunlight as a light source in MeCN-H2O at 25-30
°C and gave corresponding products in good yields. Obviously, this
organic-dye-catalysed cleavage of C-N and N-N bonds provides a
facile route for the preparation of various valuable aryl-phosphonates
and -phosphine oxides.
Table 2. Scope of 1,2,3-benzotriazin-4(3H)-one derivatives
O
N
EtO
EtO
O
or
P
O
Table 3. Scope of P-nucleophilesa
R
N
N
R
Ar
P(OEt)3
+
N
Eosin Y (5 mol %)
rt, Ar, DIPEA (2 equiv)
MeCN (2.0 mL)-H2O (0.3 mL)
Ar
H
1
2a
R1
R2
O
O
3
P
O
R1
P
or
Ph
N
N
Ph
+
N
O
O
O
OR3
R2
Eosin Y (5 mol %)
EtO
EtO
EtO
EtO
EtO
EtO
H
N
P
O
P
O
P
O
rt, Ar, DIPEA (2 equiv)
1
1
1
2
3
1a
MeCN (2.0 mL)-H2O (0.3 mL)
N
H
N
Me
N
H
H
R
MeO
MeO
O
PhO
O
P
O
P
O
3a
3b
, 87% (82%)
91% (83%)
3c
3d
3e
, R = Me, 85% (78%)
, R = Br, 82% (87%)
, R = I, 81% (77%)
OMe
P
OPh
P
PhO
Ph
Ph
N
3f
N
,
R = F, 81% (85%)
, R = Cl, 80% (78%)
, R = CF3, 78% (80%)
MeO
iPrO
iPrO
OMe
PhO
EtO
OPh
H
H
3g
3h
O
O
O
EtO
EtO
R
EtO
EtO
CF3
2b
4a, 90% (86%)
iPrO
2e
4e
, 0%
P
P
O
3i
3j
,
,
R = CO2Me, 85% (79%)
R = Me, 90% (84%)
1
1
1
EtO
Ph
O
O
N
H
N
P
O
P
O
OiPr
iPrO
OEt
P
H
t
3k
, R = Bu, 85% (72%)
I
Ph
Ph
P
N
H
N
, 75% (77%)
OiPr
3l
,
R = OMe, 86% (87%)
Ph
3n
H
3m
,R = SMe, 83% (82%)
2c
4b
, 87% (84%)
O
2f
O
O
4f
O
, 89% (83%)
O
O
EtO
EtO
F
EtO
EtO
EtO
EtO
P
P
P
O
iPrO
iPrO
P
O
1
Ph
Ph
1
P
O
P
O
OiPr
P
Ph
P
N
H
Cl
N
N
Ph
Ph
H
H
N
N
OiPr
EtO
Ph
H
H
S
S
3o
3p
3q
, 78% (72%)
, 81% (75%)
, 74% (80%)
O
2c
4c
, 86% (76%)
2g
4g
, 86% (81%)
O
O
O
EtO
EtO
EtO
EtO
EtO
EtO
P
O
O
Ph
Ph
P
O
nBuO
nBuO
O
1
P
O
Ph
P
O
OnBu
N
N
N
Ar
N
2
H
H
N
2g
Ph
H
P
N
H
MeO2C
3t
nBuO
OnBu
H
3r
, 82% (69%)
O
3s
, 86% (81%)
O
, 75% (77%)
4h,
4i
Ar = C6H5, 84% (83%)
, Ar = 4-Cl-C6H4, 86% (81%)
EtO
2d
4d
, 81% (85%)
EtO
EtO
3u,
3v
3w
3x
P
O
R = Me,87% (84%)
, R = OMe, 85% (92%)
, R = Cl, 81% (77%)
, R = Br, 86% (84%)
P
O
EtO
N
N
2
aReaction conditions: 1 (0.2 mmol), 2 (0.3 mmol), DIPEA (0.4 mmol), eosin Y
(5 mol%), MeCN (2.0 mL), H2O (0.3 mL), room temperature, blue LEDs (30
W), stirring under argon for 90 min. Isolated yield. Yields in parentheses
determined by 31P NMR analysis using nC8H17P(O) as an internal standard and
the reaction irradiated by sunlight at 25-30 oC for 6 h.
H
2
H
S
3y
, 87% (71%)
R
O
O
EtO
EtO
EtO
EtO
P
O
P
O
Ph
N
N
H
H
3z
3aa
, 0%
, trace
EtO
EtO
O
O
N
P
O
Eosin Y (5 mol %)
DIPEA (2 equiv)
OEt
rt, MeCN : H2O = (20:3)
Reaction conditions: 1 (0.2 mmol), 2a (0.3 mmol), DIPEA (0.4 mmol), eosin
Y (5 mol%), MeCN (2.0 mL), H2O (0.3 mL), room temperature, blue LEDs
(30 W), stirring under argon for 90 min. Isolated yield. Yields in parentheses
determined by 31P NMR analysis using nC8H17P(O) (: 48 ppm) as an internal
standard and the reaction irradiated by sunlight at 25-30 oC for 6 h.
OEt
P
Ph
Ph
N
N
+
N
EtO
H
time
24 h
36 h
light:
3a
1a,
2a
1.67g
, 1.87g
2.05 g, 82%
blue LEDs (30 W)
sunlight (25-30 oC)
1.95 g, 78%
Ph
O
O
N
P
O
Eosin Y (5 mol %)
DIPEA (2 equiv)
The scope of other phosphites was also examined to further
demonstrate the generality of this methodology. As depicted in Table
3, apart from 2a, other phosphites such as P(OMe)3, P(OiPr)3 and
P(OnBu)3 were all compatible in this reaction providing 4a, 4b, 4c and
4d in yields of 90%, 87%, 86% and 81%, respectively. It is a pity that
the reaction was completely blocked when triphenylphosphite was
Ph
Ar
Ph
Ar
+
N
P
N
N
rt, MeCN : H2O = (20:3)
blue LEDs (30 W)
24 h
H
EtO
Ph
1g
, 2.57g
Ar = 4-C6H4Cl
2g,
3.45g
4i
3.36g, 78%
Scheme 2. Gram-scale preparation of 3a and 4i.
taken as
a
substrate. However, benzotriazinones undergo
phosphorylation successfully with 2f and 2g to deliver the target
products (4f-4i) with excellent reaction efficiency. Triaryl tertiary
To examine the synthetic utility of this transformation gram-scale
experiments were carried out (Scheme 2). Compound 3a and 4i were
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 3
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obtained with high efficiency in the yields of 82% and 78% after to the reaction system as a radical inhibitor. Recently, significant
View Article Online
DOI: 10.1039/D0GC03613G
prolonging the blue LED irradiation time to 24 h. The pure gram-scale progress has been made in C-B bond formation though a single-
synthesized compounds were isolated just upon extraction, followed electron transfer process.15 Diboron (B2pin2) as a good radical
by re-crystallization using a petroleum ether/AcOEt mixture as the acceptor could be applied to this system to produce the
solvent; no tedious chromatographic purification was required. corresponding borylated products 6a and 6b in good yields.
Furthermore, sunlight could also effectively promote the reaction, These results suggest that this reaction may involve a radical
affording compound 3a in 78% yield.
process. Based on the above results and previous
reports,8,13c,13d,16 a plausible mechanism for the visible-light-
promoted denitrogenative of 1,2,3-benzotriazin-4-(3H)-one was
proposed. Initially, the exited-stated eosin Y (Ep/2red = 0.83 V)17
was generated under the irradiation of visible light, which was
then reductively quenched by DIPEA (Ep/2ox = 0.63 V, see ESI).
A single-electron transfer between the anion radical eosin Y•- and
Furthermore, the luminescence of eosin Y with excitation at 575
nm could be readily quenched by DIPEA (Figure 1, see ESI). This
luminescence quenching is most likely due to photoinduced electron
transfer.
ox
benzotriazinone 1 (Ep/2 = 2.04 V, see ESI) took place to
produce the radical anion A with the regeneration of ground-state
eosin Y. Intermediate A could undergo an elimination of
nitrogen to produce the corresponding aryl radical anion
intermediate B, which reacted with phosphite 2 to give the
unstable phosphoranyl radical C. The anion species D could be
obtained by releasing an alkyl radical from C, followed by the
abstraction of a proton from water to give the final desired
product 3.
Conclusions
In summary, we have developed an organic-dye-catalysed
denitrogenative phosphorylation of 1,2,3-benzotriazin-4-(3H)-
ones for the synthesis of aryl-phosphonates, -phosphinates and -
phosphine oxides. This method features low-cost organic-dye
catalysis, environmental-friendly reaction conditions, broad
substrate scope and excellent functional group compatibility.
The radical mechanism was verified by control experiments and
employment of B2pin2 as a radical acceptor. Moreover, this
method can be easily adapted to large-scale preparation. Further
investigation of the mechanism and application of this reaction
are currently underway.
Figure 1 Luminescence quenching experiments.
(a)
EtO
EtO
O
O
P
O
Ph
standard condition
TEMPO (5.0 eq.)
Ph
N
N
P(OEt)3
+
N
H
N
O
1a
1a
2a
3a,
trace
(b)
Bpin O
Ar1
Ar2
+
Ar2
standard condition
N
N
Ar1
B2pin2
N
H
N
5
, Ar1 = C6H4, Ar2 = 3-MeC6H4, 70%
, Ar1 = C4SH3, Ar2 = C6H5, 65%
6a
6b
Experimental
DIPEA
EY*
DIPEA
EY
Organic-dye-catalyzed denitrogenative phosphorylation of
benzotriazinones
O
A schlenk tube containing benzotriazinone derivatives (1, 0.2 mmol)
and eosin Y (0.01 mmol) were evacuated and purged with argon three
times. DIPEA (0.4 mmol), phosphorylation reagent (2, 0.3 mmol),
H2O (0.3 mL) and CH3CN (2.0 mL) were sequentially added to the
system at room temperature. Then the system stirred at room
temperature under the irradiation of 30 W blue LEDs for 90 min (or
irradiated by sunlight at 25-30 oC for 6 h). Afterwards, the solvent was
removed in vacuum, and residues were purified by silica gel column
chromatography using petroleum ether/ethyl acetate as the eluent
(2:1) to afford the desired phosphorylation products.
N2
O
N2
R
R
N
N
R3H
hv
A
B
R1R2POR3
EY
R2
DIPEA
1
2
R2
DIPEA
R
OR3
R1 R2
P
R1
O
R1
O
P
O
P
O
O
R3
R
R
H2O
N
N
N
H
3
D
C
Gram-scale preparation of 3a and 4i.
Scheme 3. Investigation of the reaction mechanism.
A round flask containing benzotriazinone derivatives 1a, and eosin Y
(5 mol%) were evacuated and purged with argon three times, DIPEA
(2.0 equiv), phosphorylation reagent 2a (2g) (1.5 equiv), a mixture of
H2O and CH3CN (0.3:2.0) were sequentially added to the system at
To understand the mechanism, further experiments were
conducted (Scheme 3). Only a trace amount of 3a was detected
when 2,2,6,6-tetramethyl-1-piperidinyloxy(TEMPO) was added
4 | J. Name., 2012, 00, 1-3
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Green Chemistry
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Journal Name
ARTICLE
Catal., 2018, 360, 284-289; (g) M. H.; Balakrishnan and S.
room temperature. Then the system stirred at room temperature under
the irradiation of 30 W blue LEDs for 24 hours (or irradiated by
sunlight at 25-30 oC for 36 h). Quenched with addition of potassium
carbonate and water (6 mL/1 mmol) to pH = 8.5 and extracted with
ethyl acetate (3*60 mL). The combined organic layer were removed
in vacuum, dried over with MgSO4. Recrystallization using a
petroleum ether/AcOEt mixture as the solvent to afford the desired
phosphorylation products.
View Article Online
Mannathan, Org. Lett., 2020, 22, 542-546.
DOI: 10.1039/D0GC03613G
8
9
H. Wang and S. Yu, Org. Lett., 2015, 17, 4272-4275.
(a) M. H. Balakrishnan, K. Sathriyan and S. Mannathan, Org.
Lett., 2018, 20, 3815-3818; (b) V. H. Thorat, N. S. Upadhyay
and C.-H. Cheng, Adv. Synth. Catal., 2018, 360, 4784-4789. (c)
J. Li, Y. Zheng, M. Huang and W. Li, Org. Lett., 2020, 22,
5020-5024.
10 For selected reviews, see: (a) C.-L. Sun and Z.-J. Shi, Chem.
Rev., 2014, 114, 9219-9280; (b) S. Roscales and A. G. Csák,
Chem. Soc. Rev., 2014, 43, 8215-8225; (c) R. Rossi, M. Lessi,
C. Manzini, G. Marianetti and F. Bellina, Adv. Synth. Catal.,
2015, 357, 3777-3814.
Conflicts of interest
11 For selected reviews, see: (a) J. M. R. Narayanam and C. R. J.
Stephenson, Chem. Soc. Rev., 2011, 40, 102-113; (b) C. K.
Prier, D. A. Rankic and D. W. C. MacMillan, Chem. Rev.,
2013, 113, 5322-5363; (c) K. L. Skubi, T. R. Blum and T. P.
Yoon, Chem. Rev., 2016, 116, 10035-10074; (d) X.-Y. Yu, J.-
R. Chen and W.-J. Xiao, Chem. Rev., 2020, DOI:
10.1021/acs.chemrev.0c00030; (d) I. K. Sideri, E. Voutyritsa
and C. G. Kokotos, Org. Biomol. Chem., 2018, 16, 4596-4614;
(e) X.-P. Ma, C.-M. Nong, Y.-F. Liang, P.-P. Xu, X.-Y. Guo,
C. Liang, C.-X. Pan, C.-F. Su and D.-L. Mo, Green Chem.,
2020, 22, 3827-3834.
12 For selected reviews, see: (a) D. Ravelli, M. Fagnoni and A.
Albini, Chem. Soc. Rev., 2013, 42, 97-113; (b) D. Prasad and
B. König, Chem. Commun., 2014, 50, 6688-6699; (c) N . A.
Romero and D. A. Nicewicz, Chem. Rev., 2016, 116, 10075-
10166.
13 (a) K. Luo, Y.-Z. Chen, W.-C. Yang, J. Zhu, and L. Wu, Org.
Lett., 2016, 18, 452-455; (b) P. Peng, L. Peng, G. Wang, F.
Wang, Y. Luo and A. Lei, Org. Chem. Front., 2016, 3, 749-
752; (c) R. S. Shaikh, S. J. S. Düsel and B. König, ACS Catal.,
2016, 6, 8410-8414; (d) R. Li, X. Chen, S. Wei, K. Sun, L. Fan,
Y. Liu, L. Qu, Y. Zhao and B. Yu, Adv. Synth. Catal., 2018,
360, 4807-4813.
14 (a) J. Pan, R. Zhao, J. Guo, D. Ma, Y. Xia, Y. Gao, P. Xu and
Y. Zhao, Green Chem., 2019, 21, 792-797; (b) S. Shi, J. Chen,
S. Zhuo, Z. Wu, M. Fang, G. Tang and Y. Zhao, Adv. Synth.
Catal., 2019, 361, 3210-3216; (c) J. Wu, D. Ma, G. Tang and
Y. Zhao, Org. Lett., 2019, 21, 7674-7678.
There are no conflicts to declare.
Acknowledgements
This project was supported by the National Key Research and
Development Program of China (2020YFA0608300) and NSFC
(21772163, 21778042).
Notes and references
1
For selected references, see: (a) The Chemistry of
Organophosphorous Compounds, (Ed.: F. H. Hartley), Wiley,
New York, 1996; (b) Phosphorus Chemistry II, (Ed.: L.
Montchamp), in: Topics in Current Chemistry; Springer,
Switzerland, 2015; (c) C. Schultz, Bioorg. Med. Chem., 2003,
11, 885-898; (d) S. Demkowicz, J. Rachon, M. Daśko and W.
Kozak, RSC Adv., 2016, 6, 7101-7112.
2
3
4
For selected references, see: (a) P. H. Mutin, G. Guerrero and
A. Vioux, J. Mater. Chem., 2005, 15, 3761-3768; (b) C.
Queffélec, M. Petit, P. Janvier, D. A. Knight and B. Bujoli,
Chem. Rev., 2012, 112, 3777-3807.
(a) C. Sine, Farm Chemicals Handbook, Meister Publishing
Company, Willoughby, OH, USA, 1993; (b) D. Z. Shi, Chinese
Pesticide Dictionary, Chemical Industry Press Co, Lit.,
Beijing, China, 2008.
For selected reviews, see: (a) P. Espinet and K. Soulantica,
Coord. Chem. Rev., 1999, 193, 499-556; (b) W. Tang and X.
Zhang, Chem. Rev., 2003, 103, 3029-3069; (c) Y.-M. Li, F.-Y,
Kwong, W.-Y. Yu and A. S. C. Chan, Coord. Chem. Rev.,
2007, 251, 2119-2144; (d) J. M. Bayne and D. W. Stephan,
Chem. Soc. Rev., 2016, 45, 765-774; (e) H. Ni, W.-L. Chan and
Y.Lu, Chem. Rev., 2018, 118, 9344-9411.
15 G. Yan, D. Huang and X. Wu, Adv. Synth. Catal., 2018, 360,
1040-1053.
16 W. Lecroq, P. Bazille, F. Morlet-Savary, M. Breugst, J.
Lalevée, A.-C. Gaumount and S. Lakhdar, Org. Lett., 2018, 20,
4164-4167.
17 D.-M. Yan, J.-R. Chen and W.-J. Xiao, Angew. Chem. Int. Ed.
2019, 58, 378-380.
5
6
T. Hirao, T. Masunaga, Y. Ohshiro and T. Agawa, Tetrahedron
Lett., 1980, 21, 3595-3598.
For selected reviews, see: (a) H. A. McManus and P. J. Guiry,
Chem. Rev., 2004, 104, 4151-4202; (b) J.-L. Montchamp, Acc.
Chem. Res., 2014, 47, 77-87; (c) A. Hosseinian, S. Farshbaf,
L. Z. Fekri, M. Nikpassand and E. Vessally, Top Curr.
Chem.(Z), 2018, 376, 23-42; (d) T. Chen and L.-B. Han, Synlett,
2015, 26, 1153-1163; (e) T. Chen, J. S. Zhang and L.-B. Han,
Dalton Trans., 2016, 45, 1843-1849; (f) S. Vander Jeught and
C. V. Stevens, Chem. Rev., 2009, 109, 2672-2702; (g) T.
Baumgartner and R. Réau, Chem. Rev., 2006, 106, 4681-4727.
For selected references, see: (a) T. Miura, M. Yamauchi and
M. Murakami, Org. Lett., 2008, 10, 3085-3088; (b) M.
Yamauchi, M. Morimoto, T. Miura and M. Murakami, J. Am.
Chem. Soc., 2010, 132, 54-55; (c) T. Miura, M. Morimoto, M.
Yamauchi and M. Murakami, J. Org. Chem., 2010, 75, 5359-
5362; (d) T. Miura, Y. Nishida, M. Morimoto, M. Yamauchi
and M. Murakami, Org. Lett., 2011, 13, 1429-1431; (e) Z.-J.
Fang, S.-C. Zhang, Z. Guo, J.-Y. Guo, B. Tan and X.-Y. Liu,
Angew. Chem., Int. Ed., 2015, 54, 9528-9532; (f) V. H. Thorat,
N. S. Upadhyay, M. Murakami and C.-H. Cheng, Adv. Synth.
7
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