A Decarboxylative C(sp3)?N Bond Forming Reaction to Construct 4-Imidazolidinones via Post-Ugi Cascade Sequence in One Pot

Article abstract of DOI:10.1002/adsc.202000736

A post-Ugi one-pot cascade was developed to access 4-imidazolidinones through an intramolecular decarboxylative C(sp³)?N bond forming reaction. The reaction has a broad tolerance for a variety of substituted aldehydes, anilines, isocyanides and glyoxylic acids. The cascade reaction scope was expanded to synthesize spiroimidazolidinone by the replacement of aldehyde with aliphatic ketone in the Ugi reaction. Subsequently, the methodology was applied to synthesize the core structures of pharmaceuticals GSK2137305 and SCH 900822 under the mild and facile conditions with one purification. This cascade reaction generates opportunities for the tailored synthesis of a range of biologically active 4-imidazolidinones through tuneable Ugi inputs. (Figure presented.).

Full text of DOI:10.1002/adsc.202000736

Title: A Decarboxylative C(sp3)-N Bond Forming Reaction to Construct
4-Imidazolidinones via Post-Ugi Cascade Sequence in One Pot
Authors: Guiting Song, Chuanhua Qu, Jie Lei, Yan Wei, Dianyong
Tang, Hong-yu Li, Zhongzhu Chen, and Zhigang Xu
This manuscript has been accepted after peer review and appears as an
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of the final Version of Record (VoR). This work is currently citable by
using the Digital Object Identifier (DOI) given below. The VoR will be
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content of this Accepted Article.
To be cited as: Adv. Synth. Catal. 10.1002/adsc.202000736
Link to VoR: https://doi.org/10.1002/adsc.202000736

10.1002/adsc.202000736
Advanced Synthesis & Catalysis
COMMUNICATION
DOI: 10.1002/adsc.201((will be filled in by the editorial staff))
A Decarboxylative C(sp3)-N Bond Forming Reaction to
Construct 4-Imidazolidinones via Post-Ugi Cascade Sequence in
One Pot
Gui-Ting Song,a,# Chuan-Hua Qu,a,# Jie Lei,a,b Wei Yan,b Dian-Yong Tang,a Hong-yu
Li,b* Zhong-Zhu Chen,a* Zhi-Gang Xua*
a
National & Local Joint Engineering Research Center of Targeted and Innovative Therapeutics, Chongqing Engineering
Laboratory of Targeted and Innovative Therapeutics, Chongqing Key Laboratory of Kinase Modulators as Innovative
Medicine, Chongqing Collaborative Innovation Center of Targeted and Innovative Therapeutics, College of Pharmacy
& International Academy of Targeted Therapeutics and Innovation, Chongqing University of Arts and Sciences,
Chongqing 402160, China. 18883138277@163.com; xzg@cqwu.edu.cn.
b
Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little
Rock, AR 72205, United States. HLi2@uams.edu.
These authors contributed equally to this work.
#
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.201######.((Please
delete if not appropriate))
Abstract. A post-Ugi one-pot cascade was developed to
access 4-imidazolidinones through an intramolecular
decarboxylative C(sp3)-N bond forming reaction. The
reaction has a broad tolerance for a variety of substituted
aldehydes, anilines, isocyanides and glyoxylic acids. The
cascade reaction scope was expanded to synthesize
spiroimidazolidinone by the replacement of aldehyde with
aliphatic ketone in the Ugi reaction. Subsequently, the
methodology was applied to synthesize the core structures
of pharmaceuticals GSK2137305 and SCH 900822 under
the mild and facile conditions with one purification. This
cascade reaction generates opportunities for the tailored
synthesis of
imidazolidinones through tuneable Ugi inputs.
a
range of biologically active 4-
Figure 1. Bioactive compounds containing the 4-
imidazolidinone cores.
Keywords: 4-Imidazolidinones; Spiroimidazolidinone;
Decarboxylation; One-pot; Multicomponent reactions
(MCRs)
to form the C-N bond directly.[8] Curtius
rearrangement[9a-c] (Scheme 1a), Buchwald-Hartwig
reaction[9d], reductive amination with carbonyls[9e] and
Mitsunobu reaction[9f] are very commonly used for
the preparation of C(sp3)−N bond. Very recently, the
decarboxylative C(sp3)−N cross-coupling was
reported by Fu via photoredox and copper catalysis
(Scheme 1b).[10] Another decarboxylative C(sp3)−N
formation has been developed through electro-
chemical oxidation of amino acids, which expanded
from the intramolecular to the intermolecular reaction
(Scheme 1c).[11] However, the pre-activation of
carboxylic acids is still required for the
Imidazolidin-4-one is an important structural
moiety existed in many natural products [(-)-
Dysibetaine PP],[1] pharmaceuticals [Hetacillin],[2]
and privileged scaffolds of anticonvulsant
compounds[3] and antimalarial agents[4] (Fig. 1).
Similar imidazolones were also found in both natural
products and pharmaceuticals such as Kottamide,[5]
SCH900822, GSK2137305,[6] and Glucagon Receptor
Antagonists.[7]
decarboxylation via
a
metal catalysis and/or
Owing to the importance of imidazolidin-4-one and
imidazolone, synthetic strategies were developed to
produce these types of structures. Traditional
methods for the preparation of substituted-4-
imidazolidinones depend on the condensation of α-
aminoacetamides with ketone or aldehyde substrates
photochemistry condition. The poor availability of
starting materials is another drawback.[12] Therefore,
cost-effective and environmentally-friend conditions
with simple work-ups would be still desirable. As a
part of our continued efforts to develop cascade
reactions for therapeutic development,[13] herein, we
1
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10.1002/adsc.202000736
Advanced Synthesis & Catalysis
report a novel post-Ugi 4-component (U-4CR)
cascade reaction for the synthesis of 4-imidazolones
as depicted in Scheme 1d.
equiv. of DIPA in 88% yield under microwave
irradiation at 170 °C for 10 min.
Table 1. Optimization of the cyclization step.[a]
entry solvent base
eq.
MW.
time
yield
temp.(oC) (min) (±)6a(%)[b]
1
2
3
4
5
6
7
8
9
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
TEOA 5.0
TEOA 5.0
TEOA 5.0
TEOA 5.0
TEOA 5.0
150
140
130
120
170
100
120
140
150
160
160
170
180
170
140
150
170
100
100
100
100
170
140
140
140
10
10
10
10
10
10
10
10
10
10
20
10
10
10
10
10
10
10
10
10
10
10
10
10
10
27
<10
<5
trace
62
0
DBU
DBU
DBU
DIPA
DIPA
DIPA
DIPA
DIPA
DIPE
Et3N
2.0
2.0
2.0
5.0
5.0
5.0
5.0
5.0
5.0
5.0
5.0
5.0
0
0
44
67
79
88
76
68
21
47
63
0
0
0
0
74
<5
28
<10
Scheme 1. Decarboxylative nitrogen-nucleophile
10 DMF
11 DMF
12 DMF
13 DMF
14 DMF
15 DMF
16 DMF
17 DMF
18 DMF
19 DMF
20 DMF
21 DMF
fragment coupling.
4-Bromoaniline
(1a),
benzaldehyde
(2a),
phenylglyoxylic acid (3a), and benzyl isocyanide (4a)
were stirred in methanol overnight at room
temperature to afford the Ugi adduct 5a in an
excellent yield (Table 1). The subsequent cyclization
Et3N
Et3N
K2CO3 2.0
KOH 2.0
EtONa 2.0
KOAc 2.0
o
in DMF at 150 C in the presence of triethanolamine
(TEOA) gave the decarboxylased 4-imidazolidinone
analogue (±)6a. The loss of exchangeable proton in
1H NMR spectrum and two carbonyl carbons in 13C
NMR spectrum strongly suggests a novel chemical
structure. However, the post Ugi cyclization reaction
did not initially furnish product (±)6a in an
acceptable yield (only 27%, entry 1), and required
further optimization with variations in temperature,
time, solvent, and base.
22 DMSO DIPA
23 Dioxane DIPA
24 MeCN DIPA
2.0
2.0
2.0
2.0
25 EtOH
DIPA
[a]
The reactions were carried out with 5a (0.3 mmol), base,
and solvent (1.5 mL) under microwave irradiation.
Yield (%) for compound (±)6a based on peak area of the
product by HPLC analysis at 254 nm.
[b]
Optimization studies for the cyclization of this
cascade were then conducted (Table 1). Gratifyingly,
o
o
elevating temperature from 130 C to 170 C for 10
min in DMF with TEOA improved the reaction yield
from 27% to 62% for (±)6a (entry 5). No desired
product was isolated in the presence of 1,8-
diazabicyclo[5.4.0]-undec-7-ene (DBU), which led to
the decomposition of 5a (entries 6-8). Different
temperatures and reaction times were next evaluated
with diisopropylamine (DIPA, entries 9-13), and the
yield was further improved to 88% (entry 12). Et3N
were less effective under the similar conditions to
synthesize compound (±)6a (entries 15-17) and
inorganic bases gave no desired compound (±)6a
(entries 18-21). The reaction didn’t yield compound
(±)6a in a higher yield in different solvents (DMSO,
MeCN, EtOH, and dioxane) with DIPA than in DMF
(entries 22-25). The best result was obtained with 5.0
With the optimized conditions in hand, we
proceeded to investigate the scope of the reaction to
prepare a small library of 4-imidazolidinone (±)6
(Table 2). In all cases, initial Ugi products 5 were
obtained in good yields following the removal of the
reaction solvent without further purification. A
variety of different starting materials were
successfully employed under the optimized
conditions for the construction of structurally diverse
4-imidazolidinones (±)6a-s in a diastereoselective
manner with yields in the range of 50-74%, indicating
a good functional group tolerance. In addition, the
relative stereochemistry of compound (±)6n (CCDC
1910097)[14] was unambiguously determined to be
syn-relationship between two aryl substituents by X-
2
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10.1002/adsc.202000736
Advanced Synthesis & Catalysis
ray crystallography (See SI for details). It is
noteworthy that the product of Ugi adducts 5a-s did
not require purification by column chromatography,
with the crude product having no discernible impact
on the overall yield of final products.
assembled from aliphatic ketones, anilines, α-keto
acids, and isocyanides with methanolic potassium
hydroxide to afford 2,5-dioxo-1,3-diphenyl-3-
hydroxy-1,4-diazaspiro[5.5]undecane.[17] In order to
expand the scope of this novel cascade reaction,
aldehyde was replaced with aliphatic ketone in the
Ugi reaction as shown in Table 3. Fully
substituted compound 8a was synthesized upon
the replacement of aldehyde 2a with
cyclohexanone 7a (Table 3).
Table 2. Scope of the Ugi/decarboxylation leading to
4-imidazolidinones (±)6a-s.[a]
Table 3. Optimization of the reaction conditions for
compound 9a.[a]
yield
(±)6(%)
compd
R1
R2
H
R3
Ar
entry solvent base
eq.
MW.
time
yield
4-Br
3-Br
4-Cl
3-Cl-4-F
4-OCH3
4-F
Bn
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
73
55
51
74
56
63
68
52
temp.(oC) (min) 9a (%)[b]
(±)6a
(±)6b
(±)6c
(±)6d
(±)6e
(±)6f
(±)6g
(±)6h
3,4-di-Cl Bn
4-OMe
H
1
2
3
4
5
6
7
8
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DIPA
DIPA
DIPEA
Et3N
5.0
5.0
5.0
2.0
170
180
180
180
180
120
140
160
180
180
200
200
200
180
180
180
180
200
140
120
120
10
20
20
20
20
10
10
10
10
20
10
20
30
10
10
10
10
20
20
20
20
NR
NR
NR
NR
NR
NR
NR
trace
36%
49%
68%
89%
71%
0
Bn
Bn
Bn
Bn
Bn
Bn
H
4-Me
4-Cl
H
DABCO 2.0
H
DBU
DBU
DBU
DBU
DBU
DBU
DBU
DBU
K2CO3
KOH
EtONa
KOAc
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
3,4-di-OMe
4-Br-
C6H4
H
H
Bn
57
(±)6i
9
H
3-Br
H
H
H
4-Br
H
Bn
Cy
Bn
PhC2H4
Cy
Bn
Furyl
Furyl
Ph
Ph
Ph
54
50
66
61
58
64
(±)6j
(±)6k
(±)6l
(±)6
(±)6n
(±)6o
10
11
12
13
14
15
16
17
18
19
20
21
4-Br
4-Cl
3-Br
H
4-F
Ph
4-OMe-
C6H4
0
0
4-F
4-F
4-Cl
4-Cl
H
Cy
Bn
Cy
52
60
56
(±)6p
(±)6q
(±)6r
Ph
NR
<10
NR
NR
NR
DMSO DBU
Diox
DCE
4-Br-
C6H4
4-Cl
DBU
DBU
4-OMe-
C6H4
3-Cl-4-F
H
PhC2H4
51
(±)6s
MeCN DBU
[a] The reactions were carried out with 8a (0.3 mmol), base,
and solvent (1.5 mL) under MW.
[a] Reaction conditions: 1 (0.5 mmol), 2 (0.5 mmol), 3 (0.5
mmol) and 4 (0.5 mmol) in MeOH (1.0 mL) under air;
After workup, added DIPA (5.0 eq.) in DMF (3.0 mL),
at 170 oC for 10 min under MW; isolated yields for two
steps. MW = microwave irradiation.
[b] Yield (%) for compound 9a based on peak area of the
product by HPLC analysis at 254 nm.
With compound 8a in hand, we have initially used
the previously optimized conditions (5.0 equiv. of
DIPA under microwave irradiation at 170 °C for 10
min in DMF) established in Table 3 to synthesize
compound 9a. The targeted compound 9a was not
detected unexpectedly. Further reaction condition
optimization was then investigated. Several weak
organic bases were tested firstly and the reaction
didn’t give the desired product with starting material
During the past few years, α-keto acids have been
widely used for the decarboxylative cross-coupling
reaction in the presence of metal catalysts.[15] In
addition, it has been reported for the synthesis of
nitrogen-containing heterocycles via the U-4CR with
α-keto acids in many literatures.[16] Faggi et al.
disclosed the treatment of the Ugi-4CR adducts
3
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10.1002/adsc.202000736
Advanced Synthesis & Catalysis
8a intact (Table 4, entries 1-6). When DBU was used,
a trace amount of the decarboxylative product 9a was
found under the microwave irradiation at 160 C for
Encouraged by the remarkable yield at the
optimized conditions, we investigated the scope of
this cascade reaction by varying starting materials. In
all cases, initial Ugi products 8 were obtained in good
yields following the removal of reaction solvent. The
crude Ugi products were then used directly without
further purification to give 4-imidazolidinone 9 in 51-
72% yields with four different aliphatic ketones
involved (Table 4). The chemical structure of 9q
(CCDC 1891682)[14] was confirmed through X-ray
crystallography (in the Supporting Information).
o
10 min (Table 4, entry 8). Elevating temperature to
o
200 C for 20 min, compound 9a was isolated with
89% yield. Inorganic bases didn’t give the desired
product 4-imidazolidinone 9a (entries 14-17). The 1D
and 2D NMR analysis of the decarboxylative product
9a confirmed the chemical structure of 4-
imidazolidinone (see supplementary data). Different
solvents were evaluated in the presence of DBU, and
the results were dissatisfied (entries 18-21). The
optimal conditions are therefore established as 2.0
o
equiv. DBU in DMF at 200 C for 20 min (Table 3,
entry 12).
Table 4. Scope of the Ugi/decarboxylation leading to
spiroimidazolones 9a-s.[a]
Scheme 2. A control experiment of the oxygen-
isotope distribution ratio (%) for the synthesis of
compound (±)11.
To evaluate the reaction mechanism, a control
experiment was conducted to gain mechanistic
insight in Scheme 2. In order to prove the C=O bond
of an amide involved in decarboxylation,
phenylglyoxylic acid labeled with O18 was used for
the preparation of the Ugi product 10 (see Scheme 2
and SI for details). About half amount of O18 atom
was missing from the major product (±)11 isolated
from the sequential cyclization reaction, which
confirmed the hypothesis.
yield
9 (%)
60
51
62
60
52
64
compd
R1
R3
R4
Ar
4-Br
4-OMe
4-F
3-Cl
H
Bn
Bn
Bn
Bn
Bn
Cyclohexyl
Cyclohexyl
Cyclohexyl
Cyclohexyl
Cyclohexyl
Ph
Ph
Ph
Ph
Ph
Ph
9a
9b
9c
9d
9e
9f
4-Br
Bn Cyclopentyl
3,4-di-OMe Bn Cyclopentyl Furyl
54
9g
4-Br-
C6H4
H
Bn Cyclopentyl
3-F-Bn Cyclopentyl
Bn Cyclopentyl
56
72
55
9h
9i
4-OMe-
C6H4
4-Cl
3-Br
4-OMe-
C6H4
9j
4-Br
4-Br
4-Br
3-Cl-4-F
4-Br
Bn
Bn
Cyclobutyl
dimethyl
Ph
Ph
Ph
Ph
Ph
59
68
61
65
53
9k
9l
PhC2H4 dimethyl
9m
9n
9o
9p
9q
9r
dimethyl
dimethyl
dimethyl
dimethyl
dimethyl
Bn
Cy
Bn
Scheme 3. Plausible mechanism for compounds 6
and 9.
4-F
Piperonylic 51
3,4-di-OMe Bn
Ph
59
56
4-Br
Bn
Furyl
4-Br-
C6H4
A plausible mechanism for the formation of
compounds
6 or 9 from the Ugi products 5 or 8 is
4-OMe
Cy
dimethyl
54
9s
therefore proposed in Scheme 3. Free NH from
the amide attacks the α-carbonyl to generate the
intermediate 12. The intermediate 12 could afford
the 6-member ring piperazinedione 13 after the
attack of β-carbonyl from free NH. Under the
basic conditions assisted with microwave
irradiation, the OH group would break another
[a] Reaction conditions: 1 (0.5 mmol), 7 (0.5 mmol), 3 (0.5
mmol) and 4 (0.5 mmol) in MeOH (1.0 mL) under air;
After workup, added DBU (2.0 eq.) in DMF (3.0 mL),
at 200 oC for 20 min under MW.
4
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10.1002/adsc.202000736
Advanced Synthesis & Catalysis
amide bond to provide compound 14 with a 5-
member-ring system. Upon the liberation of CO2,
a new C(sp3)-N bond would be formed after the
attack of NH to the spiro-carbon to afford
imidazolidinones and spiroimidazolones in the cancer
cell lines is in progress.
imidazolidinone
6 in a diastereoselective manner
Experimental Section
with syn-configuration or spiroimidazolidinone
9
.
Interestingly, this post-Ugi decarboxylation
occurred with the cleavage of two amide bonds
under microwave irradiation with an organic
base.
General procedures for compound 6: A solution of
amine 1 (0.50 mmol) and aldehyde 2 (0.50 mmol) in
MeOH (1 mL) was stirred at room temperature for 10 min
in a 5 mL microwave vial. Acid 3 (0.50 mmol) and
isonitrile 4 (0.50 mmol) were added to the vial sequentially,
and the resulting mixture was stirred at room temperature
overnight. Ater the reaction was completed monitoring by
TLC, the resulting reaction mixture was concentrated
under a gentle stream of nitrogen. The resulting residue
was dissolved in DMF (3 mL) with the same microwave
vial. DIPA (2.5 mmol) was then added to the vial, which
was sealed and heated under microwave irradiation at
170 °C for 10 min. The reaction mixture was then cooled
to room temperature and concentrated under reduced
pressure to give a residue, which was diluted with EtOAc
(15 mL), before being washed sequentially with 1N HCl,
saturated NaHCO3 solution and brine. The organic solution
was then dried over MgSO4 and concentrated to the residue,
which was purified by column chromatography over silica
gel eluting with a gradient of ethyl acetate/hexane (0 to
30%) to afford the relative compound 6.
Scheme 4. The synthesis of spiroimidazolidinone 18.
Yield of isolated product for one-pot procedure with
three steps.
General procedures for compound 9: A solution of
amine 1 (0.50 mmol) and ketone 7 (0.50 mmol) in MeOH
(1 mL) was stirred at room temperature for 30 min in a 5
mL microwave vial. Acid 3 (0.50 mmol) and isonitrile 4
(0.50 mmol) were added to the vial sequentially, and the
resulting mixture was stirred at room temperature
overnight. Ater the reaction was completed monitoring by
TLC, the resulting reaction mixture was concentrated
under a gentle stream of nitrogen. The resulting residue
was dissolved in DMF (3 mL) with the same microwave
vial. DBU (1.0 mmol) was then added to the vial, which
was sealed and heated under microwave irradiation at
200 °C for 20 min. The reaction mixture was then cooled
to room temperature and concentrated under reduced
pressure to give a residue, which was diluted with EtOAc
(15 mL), before being washed sequentially with 1N HCl,
saturated NaHCO3 solution and brine. The organic solution
was then dried over MgSO4 and concentrated to the residue,
which was purified by column chromatography over silica
gel eluting with a gradient of ethyl acetate/hexane (0 to
60%) to afford the relative compound 9.
The core structure of spiroimidazolidinones is
the main structural unit of GSK2137305 and SCH
900822, a glycine transporter type 1 inhibitor and
a
potent and selective glucagon receptor
antagonist, respectively.[18-19] For the synthetic
applications of this new cascade reaction, retro-
synthetically, spiroimidazolidinone 18 could be
obtained by removing 2,4-dimethoxybenzyl
group from compound 17. The synthesis of the
spiroimidazolidinone core is shown in Scheme 4.
2,4-Dimethoxybenzylamine 15, cyclohexanone
7a or cyclopentanone 7b were used to afford the
Ugi adduct 16. With the optimal conditions for
the decarboxylative cross-coupling reaction with
DBU, compound 17 could be obtained. Under the
acidic conditions with TFA, 2,4-dimethoxybenzyl
group was removed to give spiroimidazolidinone
18. This procedure provided a facile and efficient
way for the construction of functionalized
spiroimidazolidinones in one-pot and could
provide analogues to GSK2137305 and SCH
900822 for further SAR studies.
In conclusion, we have developed a post-
Ugi/decarboxylative C(sp3)-N bond formation
cascade reaction that proceeds under microwave
irradiation to construct 4-imidazolidinones and drug-
like spiroimidazolones. A small library collection of
targeted products has been prepared under mild
reaction conditions with good yields and a simple
operation procedure. This novel cascade reaction
could generate immense opportunity for the tailored
synthesis of a range of scaffolds to easily access
novel molecular space. Further screening of 4-
General procedures for compound 18: A solution of
aniline 15 (1 mmol) and ketone 7a or 7b (1 mmol) in
MeOH (2 mL) was stirred at room temperature for 10 min
in a 5 mL microwave vial. Benzoylformic acid 3a (1
mmol) and benzylisocyanide 4a (1 mmol) were added to
the vial sequentially, and the resulting mixture was stirred
at room temperature overnight. Ater the reaction was
completed monitoring by TLC, the resulting reaction
mixture was concentrated under a gentle stream of nitrogen.
The resulting residue was dissolved in DMF (3 mL) with
the same microwave vial. DBU (2.0 mmol) was then added
to the vial, which was sealed and heated under microwave
5
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10.1002/adsc.202000736
Advanced Synthesis & Catalysis
irradiation at 200 °C for 20 min. The reaction mixture was
then cooled to room temperature and concentrated under
reduced pressure to give a residue, which was diluted with
EtOAc (15 mL), before being washed sequentially with 1N
HCl, saturated NaHCO3 solution and brine. The organic
solution was then dried over MgSO4 and concentrated to
the residue, which was dissolved in 10% TFA/DCE (2 mL)
heating at 100 ℃ for 10 min. The reaction mixture was
then cooled to room temperature and concentrated under
reduced pressure to give a residue, which was diluted with
EtOAc (15 mL), before being washed saturated NaHCO3
solution and brine. The organic solution was then dried
over MgSO4 and concentrated to the residue, which was
purified by column chromatography over silica gel eluting
with a gradient of ethyl acetate/hexane (0 to 30%) to afford
the relative compound 18.
c) N. Vale, F. Nogueira, V. E. Do Rosário, P. Gomes,
R. Moreira, Eur. J. Med. Chem. 2009, 44, 2506.
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Acknowledgements
The authors would like to thank the National Natural Science
Foundation of China (No. 21901029), Chongqing Natural
Science Foundation Postdoctoral Science Foundation Project
(cstc2019jcyj-bshX0053), the Science and Technology Research
Program of Chongqing Municipal Education Commission
(KJQN201901345 and KJQN201901346) and the Scientific
Research Foundation of the Chongqing University of Arts and
Sciences (R2019FXY11). We would also like to thank Ms H.Z. Liu
and J. Xu for obtaining the LC/MS, HRMS and NMR data.
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Advanced Synthesis & Catalysis
COMMUNICATION
A Decarboxylative C(sp3)-N Bond Forming
Reaction to Construct 4-Imidazolidinones via Post-
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Adv. Synth. Catal. Year, Volume, Page – Page
Gui-Ting Song,a,# Chuan-Hua Qu,a,# Jie Lei,a,b Wei
Yan,b Dian-Yong Tang,a Hong-yu Li,b* Zhong-Zhu
Chen,a* Zhi-Gang Xua*
8
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