Iron-Catalyzed and Air-Mediated C(sp3)?H Phosphorylation of 1,3-Dicarbonyl Compounds Involving C?C Bond Cleavage

Article abstract of DOI:10.1002/adsc.202001020

A C(sp³)?H phosphorylation has been achieved via the iron-catalyzed cross-coupling reactions between 1,3-dicarbonyl compounds and P(O)?H compounds involving C?C bond cleavages with air as the oxidant. This transformation provides a straightforward way to construct C(sp³)?P bonds, leading to the formation of β-ketophosphine oxides in up to 93% yield with good functional group tolerance. (Figure presented.).

Full text of DOI:10.1002/adsc.202001020

Title: Iron-Catalyzed and Air-Mediated C(sp3)–H Phosphorylation of
1,3-Dicarbonyl Compounds Involving C–C Bond Cleavage
Authors: Yingcong Ou, Yuanting Huang, Yu Liu, Yanping Huo, Yang
Gao, Xianwei Li, and Qian Chen
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To be cited as: Adv. Synth. Catal. 10.1002/adsc.202001020
Link to VoR: https://doi.org/10.1002/adsc.202001020

10.1002/adsc.202001020
Advanced Synthesis & Catalysis
UPDATE
DOI: 10.1002/adsc.202xxxxxx
Iron-Catalyzed and Air-Mediated C(sp3)–H Phosphorylation of
1,3-Dicarbonyl Compounds Involving C–C Bond Cleavage
Yingcong Ou,a Yuanting Huang,a Yu Liu,a Yanping Huo,a Yang Gao,a Xianwei Li,a and
Qian Chena,b,*
a
School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006,
People’s Republic of China
E-mail: qianchen@gdut.edu.cn
Key Laboratory of Functional Molecular Engineering of Guangdong Province, South China University of Technology,
b
Guangzhou 510640, People’s Republic of China
Received: ((will be filled in by the editorial staff))
Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/adsc.202######.
Abstract: A C(sp3)–H phosphorylation has been achieved
(e.g., K2S2O8 or dibenzoyl peroxide) and relatively
via the iron-catalyzed cross-coupling reactions between expensive catalysts (e.g., AgOAc or fluorescein).
1,3-dicarbonyl compounds and P(O)–H compounds
involving C–C bond cleavages with air as the oxidant. This
transformation provides a straightforward way to construct
C(sp3)–P bonds, leading to the formation of β-
ketophosphine oxides in up to 93% yield with good
functional group tolerance.
Therefore, the development of a mild and cheap
synthetic protocol for the preparation of these
important compounds is still highly desirable.
Iron salts, which are considered as the ideal
catalysts, have been of particular interest due to their
characteristic of low price and low toxicity.[7] In the
past decade, iron/O2-mediated oxidative coupling
reactions have attracted increasing attention.[8] The
use of air as the more sustainable oxidant instead of
chemical oxidants is considered to be an ideal
oxidation process.[9] In addition, the generation of
phosphoryl radicals from P(O)–H compounds with
dioxygen (O2) as the initiator represents a milder
process. However, O2-initiated phosphoryl radical
reactions have received less attention.[10] Based on
our recent studies on phosphorylation reactions[10e,11]
and air-initiated sulfenylation reactions,[12] we
Keywords: phosphorylation; C(sp3)–H bonds; iron
catalysts; air; β-ketophosphine oxides
It is well-known that β-ketophosphine oxides are of
great importance in organic synthesis, coordination
chemistry and catalysis, and extractants.[1] Notably,
β-ketophosphonates have been widely used as key
synthetic precursors in the Horner-Wadsworth-
Emmons reaction, which is the most popular and
reliable method for the preparation of alkenes.[2]
Traditional methods such as the Michaelis-Arbuzov
reaction for the synthesis of β-ketophosphine oxides
are somewhat unsatisfactory (e.g., the use of halides,
low efficiency, and harsh reaction conditions).[3,4]
Recently, the reactions between phosphoryl radicals
and unsaturated compounds such as alkenes, alkynes
and enolates for accessing β-ketophosphine oxides
have been well-documented.[5] Among them, the
became interested in developing
a
C(sp3)–H
phosphorylation of carbonyl compounds under mild
conditions. Herein, we report an efficient
transformation for the synthesis of β-ketophosphine
oxides through the cross-coupling reactions between
1,3-dicarbonyl compounds and P(O)–H compounds
involving C–C bond cleavages (Scheme 1b). The
significant advantages of this report are: 1) A cheap
iron salt is employed as a catalyst; 2) Air is used as
an oxidant.
C(sp3)–H
phosphorylation
of
1,3-dicarbonyl
compounds with P(O)–H compounds involving C–C
bond cleavages provided a more straightforward way
to construct C(sp3)–P bonds.[6] For example, Dong,
Ma, Peng and co-workers reported a silver-catalyzed
oxidative C(sp3)–H/P–H cross-coupling reaction of
1,3-dicarbonyl compounds with H-phosphonates
(Scheme 1a).[6a] Most recently, Kim, Wu and co-
workers developed a visible-light-induced radical
cascade reaction of 1,3-dicarbonyl compounds with
diarylphosphine oxides.[6b] However, these methods
require the use of excess amounts of strong oxidants
Scheme 1. Metal-catalyzed C(sp3)–H phosphorylation
involving C–C bond cleavages.
1
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10.1002/adsc.202001020
Advanced Synthesis & Catalysis
Table 1. Optimization of reaction conditions.[a,b]
Table 2. Scope of P(O)–H compounds.[a,b]
Yield of
3aa [%]
Entry [Fe]
Base
Solvent
1
Fe(OAc)2
THF
0
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17[c]
18[d]
19[e]
Fe(OAc)2
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
Cs2CO3 CH3CN
K3PO4
DBU
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
THF
THF
DCE
DMSO
Toluene 22
45
Trace
5
Fe(OAc)2
Fe(OAc)2
Fe(OAc)2
Fe(OAc)2
Fe(OAc)2
Fe(OAc)2
Fe(OAc)2
FeCl2
50
CH3CN
62
33
55
12
54
39
45
46
66
70
54
89
25
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
FeCl3
Fe2(SO4)3
FeCl2·4H2O
FeCl3·6H2O
FeSO4·7H2O K2CO3
FeSO4·7H2O K2CO3
FeSO4·7H2O K2CO3
FeSO4·7H2O K2CO3
[a] Reaction conditions: a 50 mL vial was charged with 1a
(0.2 mmol), 2a (0.6 mmol), iron salt (0.02 mmol) and base
(0.4 mmol) in solvent (2 mL) and sealed under air
[a] Reaction conditions: a 50 mL vial was charged with 1a
(0.2 mmol), 2 (0.6 mmol), FeSO4·7H2O (0.02 mmol) and
K2CO3 (0.4 mmol) in CH3CN (2 mL) and sealed under air
o
atmosphere (1 atm), and the mixture was stirred at 80 C
o
for 12 h. [b] Yield based on 1a was determined by 1H NMR
atmosphere (1 atm), and the mixture was stirred at 100 C
for 12 h. [b] Isolated yield based on 1a. [c] The reaction was
performed in a 4 mmol scale (0.9 g of 1a) under an open
air atmosphere at reflux for 12 h. [d] Cu(OTf)2 instead of
FeSO4·7H2O.
[c]
analysis using an internal standard.
FeSO4·7H2O (5
mol%) was employed. [d] The reaction was carried out at
100 oC. [e] The reaction was carried out at 60 oC.
The reaction conditions were tested using a model
reaction of 1,3-dicarbonyl compound 1a with
diphenylphosphine oxide 2a catalyzed by an iron salt
(10 mol%) under air, and the results were shown in
Table 1. Initially, no reaction occurred when the
reaction was carried out in the presence of Fe(OAc)2
at 80 oC in THF (entry 1). To our delight, the desired
β-ketophosphine oxide 3aa was obtained in 45%
yield with the addition of 2 equiv of K2CO3 (entry 2).
When the reaction was performed without a catalyst,
only trace amounts of 3aa were detected (entry 3),
which indicated the importance of the iron salt. We
then turned our attention to the screening of solvents
(entries 4–7), and found that CH3CN was the
optimum solvent, leading to the formation of 3aa in
62% yield (entry 7). A screening of bases was also
carried out (entries 8–10), and K2CO3 was proved to
be the optimum base. Switching the catalyst from
Fe(OAc)2 to a variety of iron salts (entries 11–16)
showed that FeSO4·7H2O was the optimum catalyst
(70% yield, entry 16). A decrease in the amount of
FeSO4·7H2O (5 mol%) led to a lower yield (54%,
entry 17). Pleasingly, a yield of 89% was achieved
when the reaction was carried out at 100 oC (entry 18),
while the product yield was significantly decreased
when the temperature was set at 60 oC (entry 19).
With the optimized reaction conditions in hand
(Table 1, entry 18), we then set out to explore the
generality of this C(sp3)–H phosphorylation. We first
applied the optimized conditions to the coupling of
1a with a variety of P(O)–H compounds 2, and the
results were illustrated in Table 2. Pleasingly,
diarylphosphine oxides bearing different groups such
as Me, OMe and Cl at the para, meta, or ortho
position of aromatic rings were all applicable to the
reaction. The corresponding β-ketophosphine oxides
3aa–3ag were isolated in good to high yields (65–
92%) yields. It is noteworthy that the reaction of 1a
with ethyl phenylphosphinate afforded the desired β-
ketophosphinate 3ah in 35% yield. We then turned to
dialkylphosphine oxides. The reaction of 1a with
dibenzylphosphine oxide gave the desired 3ai in 53%
yield, while the employment of dibutylphosphine
oxide failed to give the desired 3aj. In addition, the
reactions of 1a with dialkylphosphites were
performed under standard conditions using Cu(OTf)2
instead of FeSO4·7H2O, and the corresponding β-
ketophosphonates 3ak and 3al were isolated in
moderate yields (see Table S2 in the Supporting
Information for more details). The scale-up of the
reaction of 1a with 2a was also attempted under an
2
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10.1002/adsc.202001020
Advanced Synthesis & Catalysis
open air atmosphere at reflux. When we increased the
scale of the reaction from 0.2 to 4 mmol, 3aa was
isolated in 54% yield (0.69 g).
group, selectively gave the corresponding products
3aa–3ca and 3ea–3pa in 43–75% yields as major
regioisomers (see Table S2 in the Supporting
Information for more details). These results showed
that the C–C bond cleavages mainly took place at
C2–C3 bonds, suggesting that acetyl group could be
preferred in the decarboxylation process. When
strong electron-withdrawing groups (CF3 or CN)
were introduced into the aromatic rings of 1-aryl-3-
methyl-β-diketones, C1–C2 bond cleavages became
predominant, leading to the formation of 3da in
moderate yields as a single regioisomer. In addition,
this reaction was successfully applied to heteroaryl-
substituted diketones to afford the corresponding
products 3qa–3sa in moderate yields. Moreover, in
the reaction of ethyl benzoylacetate with 2a, only a
single regioisomer 3ta was formed in 41% yield
involving the decarboxylation of benzoyl group.
To gain more insight into the mechanism of the
reaction, a couple of control experiments were
conducted (Scheme 2). When the reaction of 1a with
2a was carried out under N2, 3aa was not detected
(Scheme 2a), suggesting that an aerobic oxidation
might be involved in the reaction. When the radical
scavenger TEMPO (2,2,6,6-tetramethylpiperidine N-
oxyl) was employed under standard conditions, the
desired reaction was completely inhibited, and the
TEMPO-P(O)Ph2 adduct 4 was detected by LC-MS
(Scheme 2b), indicating that a phosphoryl radical
reaction pathway might be involved. In order to
confirm whether phosphoryl radicals were initiated
by iron salts, we carried out the reaction of 1a with
2a under N2 using excess amounts of Fe2(SO4)3
instead of air (Scheme 2c). The results (3aa, 0% yield)
showed that iron salts might not be the initiator,
suggesting that O2 (air) should initiate the radical
reaction.[10]
Table 3. Scope of 1,3-dicarbonyl compounds.[a,b]
[a] Reaction conditions: a 50 mL vial was charged with 1
(0.2 mmol), 2a (0.6 mmol), FeSO4·7H2O (0.02 mmol) and
K2CO3 (0.4 mmol) in CH3CN (2 mL) and sealed under air
o
atmosphere (1 atm), and the mixture was stirred at 100 C
for 12 h. [b] Isolated yield based on 1.
Next, the C(sp3)–H phosphorylation of various 1,3-
dicarbonyl compounds 1 with 2a under standard
conditions was examined (Table 3). The results
showed that symmetric 1,3-diaryl-β-diketones
bearing electron-donating groups (para-OMe) or
electron-withdrawing groups (para-Br) were well-
tolerated, leading to the formation of 3ba and 3ca in
93% and 74% yields, respectively. Unfortunately, the
reaction of symmetric 1,3-dimethyl-β-diketone with
2a afforded the desired 3da in only 28% yield.
Notably, 3ba was obtained in 76% yield as a single
regioisomer when unsymmetric 1,3-diaryl-β-diketone
(para-OMe and para-CN) was employed. The more
electron-deficient benzoyl group (para-CN) might
Scheme 2. Mechanistic studies.
undergo
a
more rapid decarboxylation. The
employment of unsymmetric 1-aryl-3-methyl-β-
i
diketones bearing different groups (Me, OMe, Pr, F,
Cl and Br) at the para, meta, or ortho position of
aromatic rings, as well as the bulky 2-naphthaleneyl
3
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10.1002/adsc.202001020
Advanced Synthesis & Catalysis
Acknowledgements
We thank the Science and Technology Planning Project of
Guangdong Province (No. 2017A010103044), the Technology
Plan of Guangdong Province (No. 2019A050510042), the
Guangdong Basic and Applied Basic Research Foundation (Nos.
2019B1515120023 and 2019B1515120035), and the Open Fund
of the Key Laboratory of Functional Molecular Engineering of
Guangdong Province (No. 2016kf07, South China University of
Technology) for financial support.
References
[1] a) D. J. Fox, D. S. Pedersen, S. Warren, Chem.
Commun. 2004, 2598–2599; b) G. Mehta, K. Pallavi, J.
D. Umarye, Chem. Commun. 2005, 4456–4458; c) D. J.
Fox, S. Parris, D. S. Pedersen, C. R. Tyzack, S. Warren,
Org. Biomol. Chem. 2006, 4, 3108–3112; d) C. Clarke,
S. Foussat, D. J. Fox, D. S. Pedersen, S. Warren, Org.
Biomol. Chem. 2009, 7, 1323–1328; e) T. Sawada, M.
Nakada, Org. Lett. 2013, 15, 1004–1007; f) W. Tang, X.
Zhang, Chem. Rev. 2003, 103, 3029–3070; g) H. A.
McManus, P. J. Guiry, Chem. Rev. 2004, 104, 4151–
4202; h) M. Wei, X. Liu, J. Chen, J. Radioanal. Nucl.
Chem. 2012, 291, 717–723; i) L. A. Mitchell, B. J.
Holliday, ACS Macro. Lett. 2016, 5, 1100–1103.
Scheme 3. Proposed mechanism.
Based on the above experimental results and
previous reports,[6,8,10] a plausible mechanism was
proposed (Scheme 3). Initially, phosphoryl radical 5
is generated by the autoxidation of P(O)–H
compound 2 in the presence of O2 and K2CO3.[10e]
Meanwhile, enolate 6 is formed via the complexation
of 1,3-dicarbonyl compound 1 with iron salts. Thus,
intermediate 7 was produced by the radical addition
of 5 to 6. Then, C-centered radical 7 is oxidized by
the iron salt to generate the direct phosphorylation
product 8 and Fe(II), which is reoxidized to Fe(III) by
O2.[8] Finally, the decarboxylation via the C–C bond
cleavage affords the desired product 3 through the
nucleophilic attack of H2O on the more electron-
deficient carbonyl group of 8.[6]
In summary, we have developed the iron-catalyzed
and air-mediated C(sp3)–H phosphorylation of 1,3-
dicarbonyl compounds involving C–C bond
cleavages. Compared with previous reports,[6] this
process is cheap and mild by using an iron salt as the
catalyst and using air as both oxidant and phosphoryl
radical initiator. The inexpensive, simple, and
efficient synthesis of extremely important β-
ketophosphine oxides with good functional group
tolerance showcases the potential of this approach in
organic synthesis.
[2] J. A. Bisceglia, L. R. Orelli, Curr. Org. Chem. 2015, 19,
744–775.
[3] a) B. A. Arbuzov, Pure Appl. Chem. 1964, 9, 307–335;
b) A. K. Bhattacharya, G. Thyagarajan, Chem. Rev.
1981, 81, 415–430; c) S. Megati, S. Phadtare, J.
Zemlicka, J. Org. Chem. 1992, 57, 2320–2327; d) P.-Y.
Renard, P. Vayron, E. Leclerc, A. Valleix, C.
Mioskowski, Angew. Chem. Int. Ed. 2003, 42, 2389–
2392; e) J. P. Abell, H. Yamamoto, J. Am. Chem. Soc.
2008, 130, 10521–10523; f) J. Guin, Q. Wang, M. van
Gemmeren, B. List, Angew. Chem. Int. Ed. 2015, 54,
355–358.
[4] a) N. A. Portnoy, C. J. Morrow, M. S. Chattha, J. C.
Williams, A. M. Aguiar, Tetrahedron Lett. 1971, 12,
1397–1400; b) D. Cavalla, C. Guéguen, A. Nelson, P.
O’Brien, M. G. Russell, S. Warren, Tetrahedron Lett.
1996, 37, 7465–7468; c) R. R. Milburn, K. McRae, J.
Chan, J. Tedrow, R. Larsen, M. Faul, Tetrahedron Lett.
2009, 50, 870–872; d) A. E. Antoshin, Y. N. Reikhov, K.
V. Tugushov, I. V. Rybaľchenko, V. F. Taranchenko, S.
A. Lermontov, A. N. Malkova, Russ. J. Gen. Chem.
2009, 79, 2113–2115; e) X. Li, G. Hu, P. Luo, G. Tang,
Y. Gao, P. Xu, Y. Zhao, Adv. Synth. Catal. 2012, 354,
2427–2432; f) P. Schroll, B. König, Eur. J. Org. Chem.
2015, 309–313.
Experimental Section
General Procedure for the Synthesis of β-
Ketophosphine Oxides
A 50 mL vial was charged with 1,3-dicarbonyl compound
1[13] (0.2 mmol), P(O)–H compound 2[14] (0.6 mmol),
FeSO4·7H2O (0.02 mmol) and K2CO3 (0.4 mmol) in
CH3CN (2 mL) and sealed under air atmosphere (1 atm),
and the mixture was stirred at 100 oC for 12 h. The reaction
solution was then cooled to room temperature and
quenched with saturated aqueous NaCl solution (20 mL).
The resulting mixture was extracted with ethyl acetate (3 ×
20 mL). The combined organic layers were dried over
anhydrous Na2SO4 and concentrated under reduced
pressure. The crude product was purified by flash column
chromatography on silica gel using ethyl acetate in
petroleum ether as the eluent to afford pure β-
ketophosphine oxide 3.
[5] a) J. Ke, Y. Tang, H. Yi, Y. Li, Y. Cheng, C. Liu, A. Lei,
Angew. Chem. Int. Ed. 2015, 54, 6604–6607; b) P.
Zhang, L. Zhang, Y. Gao, J. Xu, F. Hua, G. Tang, Y.
Zhao, Chem. Commun. 2015, 51, 7839–7842; c) Y.
Zeng, D. Tan, W. Lv, Q. Li, H. Wang, Eur. J. Org.
Chem. 2015, 4335–4339; d) Y. Zhou, M. Zhou, M.
Chen, J. Su, J. Du, Q. Song, RSC Adv. 2015, 5,
103977–103981; e) M. Bu, G. Lu, C. Cai, Catal. Sci.
Technol. 2016, 6, 413–416; f) Y. Zhou, C. Rao, S. Mai,
Q. Song, J. Org. Chem. 2016, 81, 2027–2034; g) Q. Fu,
4
This article is protected by copyright. All rights reserved.

10.1002/adsc.202001020
Advanced Synthesis & Catalysis
D. Yi, Z. Zhang, W. Liang, S. Chen, L. Yang, Q. Zhang,
Kozlowski, Chem. Rev. 2013, 113, 6234–6458; e) C.
Liu, D. Liu, A. Lei, Acc. Chem. Res. 2014, 47, 3459–
3470.
J. Ji, W. Wei, Org. Chem. Front. 2017, 4, 1385–1389; h)
W. Liang, Z. Zhang, D. Yi, Q. Fu, S. Chen, L. Yang, F.
Du, J. Ji, W. Wei, Chin. J. Chem. 2017, 35, 1378–1382;
i) Z.-J. Zhang, D. Yi, Q. Fu, W. Liang, S.-Y. Chen, L.
Yang, F.-T. Du, J.-X. Ji, W. Wei, Tetrahedron Lett. 2017,
58, 2417–2420; j) X. Chen, X. Chen, X. Li, C. Qu, L.
Qu, W. Bi, K. Sun, Y. Zhao, Tetrahedron 2017, 73,
2439–2446; k) P. Zhou, B. Hu, L. Li, K. Rao, J. Yang, F.
Yu, J. Org. Chem. 2017, 82, 13268–13276; l) C.-K. Li,
Z.-K. Tao, Z.-H. Zhou, X.-G. Bao, S.-F. Zhou, J.-P. Zou,
J. Org. Chem. 2019, 84, 2351–2357.
[10] a) T. Hirai, L.-B. Han, Org. Lett. 2007, 9, 53–55; b) W.
Wei, J.-X. Ji, Angew. Chem. Int. Ed. 2011, 50, 9097–
9099; c) K. Luo, Y.-Z. Chen, L.-X. Chen, L. Wu, J. Org.
Chem. 2016, 81, 4682–4689; d) P. Peng, Q. Lu, L. Peng,
C. Liu, G. Wang, A. Lei, Chem. Commun. 2016, 52,
12338–12341; e) Y. Ou, Y. Huang, Z. He, G. Yu, Y.
Huo, X. Li, Y. Gao, Q. Chen, Chem. Commun. 2020, 56,
1357–1360.
[11] a) Q. Chen, X. Yan, Z. Du, K. Zhang, C. Wen, J. Org.
Chem. 2016, 81, 276–281; b) Q. Chen, X. Yan, C. Wen,
J. Zeng, Y. Huang, X. Liu, K. Zhang, J. Org. Chem.
2016, 81, 9476–9482; c) Q. Chen, J. Zeng, X. Yan, Y.
Huang, C. Wen, X. Liu, K. Zhang, J. Org. Chem. 2016,
81, 10043–10048; d) Q. Chen, C. Wen, X. Wang, G. Yu,
Y. Ou, Y. Huo, K. Zhang, Adv. Synth. Catal. 2018, 360,
3590–3594; e) Q. Chen, X. Wang, G. Yu, C. Wen, Y.
Huo, Org. Chem. Front. 2018, 5, 2652–2656; f) X.
Wang, Y. Ou, Z. Peng, G. Yu, Y. Huang, X. Li, Y. Huo,
Q. Chen, J. Org. Chem. 2019, 84, 14949–14956.
[6] a) L. Li, W. Huang, L. Chen, J. Dong, X. Ma, Y. Peng,
Angew. Chem. Int. Ed. 2017, 56, 10539–10544; b) X.
Zhao, M. Huang, Y. Li, J. Zhang, J. K. Kim, Y. Wu,
Org. Chem. Front. 2019, 6, 1433–1437.
[7] a) C. Bolm, J. Legros, J.-L. Le Paih, L. Zani, Chem.
Rev. 2004, 104, 6217–6254; b) L.-X. Liu, Curr. Org.
Chem. 2010, 14, 1099–1126; c) I. Bauer, H.-J. Knölker,
Chem. Rev. 2015, 115, 3170–3387.
[8] For recent examples, see: a) T. Shen, Y. Yuan, S. Song,
N. Jiao, Chem. Commun. 2014, 50, 4115–4118; b) B.
Xiong, X. Zeng, S. Geng, S. Chen, Y. He, Z. Feng,
Green Chem. 2018, 20, 4521–4527; c) S. Geng, B.
Xiong, Y. Zhang, J. Zhang, Y. He, Z. Feng, Chem.
Commun. 2019, 55, 12699–12702; d) A. Bhowmik, R.
A. Fernandes, Org. Lett. 2019, 21, 9203–9207; e) L.-S.
Huang, D.-Y. Han, D.-Z. Xu, Adv. Synth. Catal. 2019,
361, 4016–4021; f) Z.-Y. Tan, K.-X. Wu, L.-S. Huang,
R.-S. Wu, Z.-Y. Du, D.-Z. Xu, Green Chem. 2020, 22,
332–335; g) Y.-H. Lai, R.-S. Wu, J. Huang, J.-Y. Huang,
D.-Z. Xu, Org. Lett. 2020, 22, 3825–3829; h) R.-M. Hu,
D.-Y. Han, N. Li, J. Huang, Y. Feng, D.-Z. Xu, Angew.
Chem. Int. Ed. 2020, 59, 3876–3880.
[12] a) Q. Chen, G. Yu, X. Wang, Y. Huang, Y. Yan, Y. Huo,
Org. Biomol. Chem. 2018, 16, 4086–4089; b) Q. Chen,
G. Yu, X. Wang, Y. Ou, Y. Huo, Green Chem. 2019, 21,
798–802.
[13] For the preparation of 1,3-dicarbonyl compounds
which were not commercially available, see: a) N. C.
Duncan, C. M. Garner, T. Nguyen, F. Hung, K.
Klausmeyer, Tetrahedron Lett. 2008, 49, 5766–5769;
b) F. Berti, S. Bincoletto, I. Donati, G. Fontanive, M.
Fregonese, F. Benedetti, Org. Biomol. Chem. 2011, 9,
1987–1999.
[14] For the preparation of secondary phosphine oxides
which were not commercially available, see: a) H. R.
Hays, J. Org. Chem. 1968, 33, 3690–3694; b) M. J. P.
Harger, S. Westlake, Tetrahedron 1982, 38, 1511–1515.
[9] a) Z. Shi, C. Zhang, C. Tang, N. Jiao, Chem. Soc. Rev.
2012, 41, 3381–3430; b) W. Wu, H. Jiang, Acc. Chem.
Res. 2012, 45, 1736–1748; c) A. N. Campbell, S. S.
Stahl, Acc. Chem. Res. 2012, 45, 851–863; d) S. E.
Allen, R. R. Walvoord, R. Padilla-Salinas, M. C.
5
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