Photoredox asymmetric catalytic enantioconvergent substitution of 3-chlorooxindoles

Article abstract of DOI:10.1039/c9cc05304b

An enantioconvergent substitution of 3-substituted 3-chlorooxindoles with N-aryl glycines under visible light irradiation is reported. A transition-metal-free cooperative catalysis platform with a dicyanopyrazine-derived chromophore (DPZ) as a photoredox catalyst and a chiral Br?nsted acid catalyst is effective for these transformations, which involve a single-electron transfer redox step and an enantioselective radical coupling. A variety of valuable chiral 3-aminomethylene-3-substituted oxindoles can be directly synthesized with high yields and enantioselectivities.

Full text of DOI:10.1039/c9cc05304b

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DOI: 10.1039/C9CC05304B
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Photoredox Asymmetric Catalytic Enantioconvergent Substitution
of 3-Chlorooxindoles
Guangkuo Zeng,a,¶ Yunqiang Li,a,¶ Baokun Qiao,a Xiaowei Zhao,*,a and Zhiyong Jiang*,a,b
Received 00th January 20xx,
Accepted 00th January 20xx
DOI: 10.1039/x0xx00000x
An enantioconvergent substitution of 3-substituted 3- for the formation of new C−C bonds.9g The excellent
chlorooxindoles with N-aryl glycines under visible light irradiation enantioselectivity makes this decarboxylative alkylation
is reported. A transition-metal-free cooperative catalysis platform method quite useful, even though the energy barrier of the
with
a
dicyanopyrazine-derived chromophore (DPZ) as
a
radical coupling is rather low.10 As an extension, we sought to
photoredox catalyst and a chiral Brønsted acid catalyst is effective expand the scope of this sustainable strategy to cyclic alkyl
for these transformations, which involve a single-electron transfer halides, enlarging the accessible chemical space and enriching
redox step and an enantioselective radical coupling. A variety of the synthetic toolboxes of chemists.
valuable chiral 3-aminomethylene-3-substituted oxindoles can be
Selected natural and non-natural bioactive molecules
directly synthesized with high yields and enantioselectivities.
MeO
O
Me
O
S
Alkyl halides are a large class of readily accessible feedstocks
N
NH
N
N
Me
OMe
and are of central importance in organic synthesis.1 The
introduction of diverse molecular fragments on their sp3-
hybridized carbon atoms via nucleophilic substitution reactions
using the halide (X) as the directing group to achieve the precise
construction of valuable and complex molecules remarkably
increases their utility.2 SN1 and SN2 reactions are two classic
pathways for such substitutions.2,3 Nevertheless, their intrinsic
working mechanisms make SN1 reactions poorly suited3,4 and
SN2 reactions impossible3 for the enantioselective formation of
a stereocentre at the carbon of a racemic alkyl halide
undergoing substitution. To address this significant scientific
issue, Fu pioneered a study to provide key insights into the
establishment of a bimetallic protocol merging transition-
metal-catalysed cross-coupling techniques with radical
chemistry, in which the generation of achiral alkyl radicals from
racemic alkyl halides via an inner-sphere single-electron
transfer (SET) process with a chiral transition-metal catalyst is a
crucial process.3,5 This success recently inspired us to develop a
photoredox catalysis-enabled outer-sphere SET strategy6 to
produce alkyl radicals7 from acyclic α-bromoketones; an
extrinsic chiral H-bonding catalyst8,9 was responsible for
providing stereocontrol in the enantioselective radical coupling
O
MeO
O
O
O
Me
N
N
Me
N
H
HN
N
Me
H
N
O
Ph
N
Me
O
Me
I:
II:
III:
IV:
analgesic
anti-inflammatory
5-HT7 receptor ligand
MeO
Horsfiline
N
CN
CN
Ar
S
S
N
Cl
R'
N
MeO
R''
(DPZ)
O
ArHN
COOH
+
O
SPINOL-CPA
3 W blue LED
N
N
R
R
Redox neutral radical coupling
R' = aryl, benzyl
allyl, alkyl
up to 96% yield
up to 98% ee
Scheme 1 Outline of this work.
Oxindole is a ubiquitous cyclic molecular architecture in
natural and non-natural bioactive compounds.11 Among these
compounds, the derivatives that feature an α-aminomethylene
group on the 3-quaternary carbon stereocentre represent an
important class family of compounds and are common,12 such
as anti-inflammatory I bearing a 3-methyl group,12a 5-HT7
receptor ligand II containing a 3-aryl moiety,12b and natural
product horsfiline (III)12c-d and analgesic IV12e featuring five- and
six-membered ring-based spirocyclic stereogenic centres
(Scheme 1). As such, a direct and general catalytic asymmetric
strategy to access enantioenriched manifolds is an important
target, which represents a highly desirable task due to no
examples reported, although asymmetric Mannich reaction of
3-substituted 2-oxindoles with imines has been established well
since 2008.13a We envisioned that an enantioconvergent
substitution of 3-substituted-3-halooxindoles by reductive
precursors of α-aminomethylene radical via a photoredox
catalytic radical coupling would be an ideal pathway, as it would
a. Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province,
Henan University, Jinming Campus, Kaifeng, Henan, 475004, P. R. China
E-mail:chmjzy@henu.edu.cn; jiangzhiyong@htu.edu.cn
b. Henan Key Laboratory of Organic Functional Molecule and Drug Innovation,
School of Chemistry and Chemical Engineering, Henan Normal University,
Xinxiang, Henan, 453007, P. R. China
¶The authors made equal contributions.
Electronic Supplementary Information (ESI) available: [details of any supplementary
information available should be included here]. See DOI: 10.1039/x0xx00000x
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allow the straightforward introduction of an aminomethylene tosyl [Ts]> tert-butyloxycarbonyl [Boc] > Bn > Me, entries 1−4,
View Article Online
DOI: 10.1039/C9CC05304B
group on the 3-position without requiring further tedious see Table S1 in the SI). Moreover, 3-chlorooxindole presented a
modifications. Notably, the radical species generated from the better yield than the corresponding 3-bromooxindole with the
SET reduction of 3-substituted-3-halooxindoles are less stable same N-substituent (see entries 4 and 34, Table S1 in the SI).
than merostabilized dioxindolyl radicals.14 In addition, the The results demonstrated the feasibility of this plan and
weaker electron-withdrawing ability of amides relative to revealed some factors that can be used to improve the
ketones should decrease the electrophilicity of α-radicals. chemoselectivity, including a Brønsted acid (BA) catalyst (see
Furthermore, in the context of distinct 3-substituents, the α- entry 5, Table S1 in the SI). As such, we speculated that a chiral
radicals feature remarkably different electrophilicities. BA catalyst could provide enantiocontrol in the formation of
Accordingly, the reactivity and universality of their coupling new C−C bonds and thus examined a range of CPAs and reaction
with nucleophilic and transient α-aminomethylene radicals parameters (see Table S1 in the SI). To our delight, the reaction
pose a great challenge.15 With respect to the formation of between 2a and 3-benzyl-substituted 3-chloroxindole 1a with 4-
challenging full carbon quaternary stereocentres, the high fluorobenzenesulfonyl as the N-substituent afforded chiral
reactivity of the radical coupling should give rise to a product 3a in 85% yield with 90% ee when the reaction was
competitive racemic background reaction and poor conducted in a suitable solvent (MTBE/THF = 5:1) at −42 °C for
stereocontrol. Here, we report the investigation and realization 60 h in the presence of 1.0 mol% DPZ, 20 mol% SPINOL-CPA (C1)
of this attractive but defiant scenario by using a cooperative and 3.0 equiv. of KHCO3 (entry 1, Table 1). The control
organophotoredox and H-bonding catalytic system involving experiments revealed the substantial influence of the
our developed the dicyanopyrazine-derived chromophore (DPZ) substituents at the 6,6’-positions of SPINOL on the
as
a a 1,1ʹ-spirobiindane-7,7ʹ-diol enantioselectivity of the reaction; as an example, catalysts C2
photosensitizer9 and
(SPINOL)-based chiral phosphoric acid (CPA) catalyst (Scheme 1). and C3 provided 3a in 80% ee and 31% ee, respectively (entries
The careful choice of N-protective group for 3-halooxindoles is 2 and 3). [Ru(bpy)3]Cl2, a plausible photoredox catalyst, could
crucial for allowing the collective syntheses of these valuable not promote the transformation, probably due to its poor
chiral oxindole derivatives in high yields with good to excellent catalytic activity at such low temperatures (entry 4). In addition,
enantioselectivities.
the use of Rose Bengal as an organic dye gave 3a in 64% yield
with 79% ee (entry 5). In the absence of chiral catalyst C1, 3a
was observed but difficult to isolate because the reaction was
messy (entry 6). The results demonstrate the occurrence of
racemic background reactions and the importance of the chiral
acid catalyst in the chemoselectivity (entry 6). No reaction was
observed without DPZ, which excludes an EDA mechanism in
this reaction system (entry 7).16 Visible light and the oxygen-free
environment were shown to be essential to the transformation
(entries 8 and 9).
Table 1 Optimization of the reaction conditionsa
Ar
1.0 mol% DPZ
O
P
O
NHPMP
Bn
O
Cl
Bn
C1
20 mol%
OH
PMP
3.0 equiv. KHCO3
MTBE/THF = 5:1
-42 oC, argon
O
+
N
COOH
O
N
H
N
Ar
R
R
C1
C2
C3
: Ar = 9-anthryl
: Ar = 1-naphthyl
: Ar = 4-ClC6H4
3 W blue LED, 60 h
1a
: R = 4-FPhSO2-
2a
3a
Entry
Variation from standard conditions
None
Yieldb (%)
85
71
54
N.R.
64
messy
N.R.
N.R.
N.R.
eec (%)
90
1
2
3
4
5
6
7
8
9
To explore the scope of this enantioconvergent substitution
C2 instead of C1
C3 instead of C1
[Ru(bpy)3]Cl2 instead of DPZ
Rose Bengal instead of DPZ
No C1
No DPZ
No light
Under air
80
31
protocol,
chlorooxindoles were subjected to the optimal reaction
conditions. series of N-4-fluorobenzenesulfonyl-3-
a wide range of racemic 3-substituted 3-
N.A.
79
N.A.
N.A.
N.A.
N.A.
A
chlorooxindoles that feature diverse 3-benzyl groups were first
examined (Scheme 2). The results showed that all reactions
were complete within 60 h and afforded desired products 3a-p
in 63−95% yields with 80−93% ees. Distinct electron-
withdrawing and electron-donating substituents at the para-
and meta-positions of the aromatic rings of the benzyl moieties
gave similar excellent enantioselectivities. With respect to the
ortho-substituents (3d, 3i and 3n), only an electron-donating
a Reaction conditions: 1a (0.05 mmol) and 2a (0.1 mmol) in the mixed solvent (1.5
mL, MTBE/THF = 5:1). b Yield of isolated product. c Determined by HPLC analysis on
a chiral stationary phase. MTBE = methyl tert-butyl ether. N.A. = not available.
Given the ability to smoothly cleave the C−N bond, we began
our investigation by selecting 4-methoxy-phenyl (PMP)-
protected glycine (2a) as the precursor of the α-
aminomethylene radical to evaluate the reactions with 3-
benzyl-substituted 3-halooxindoles as the coupling partners
(see Table S1 in the Supporting Information [SI]). The N-
protective groups of oxindoles dramatically affected the
chemoselectivity, and the transformations were almost
completed within 24 h when using 10 mol% of diphenyl
phosphate (C18) as the catalyst; N-protective groups with
stronger electron-withdrawing abilities gave higher yields (e.g.,
methoxy (3n) group led to
a
slightly decreased
enantioselectivity (80% ee). The excellent chemical yields and
ee values obtained with fused aromatic (3o) and
heteroaromatic (3p) rings at the α-position of the methylene
highlight the generality of this catalytic system. We then
expanded this method to 3-alkyl-substituted 3-chlorooxindoles
to synthesize highly valuable substituted products with
important bioactive properties (see molecules I, III and IV in
2 | J. Name., 2012, 00, 1-3
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1.0 mol% DPZ
C1
3.0 equiv. KHCO3
MTBE/THF = 5:1
-42 oC, argon
Ph
NHPMP
R'
Cl
R'
View Article Online
20 mol%
PMP
DOI: 10.1039/C9CC053P0h4B
1.0 mol% DPZ
C23
3.0 equiv. KHCO3
MTBE/THF = 2:1
-55 oC, argon
NHAr'
O
+
N
COOH
O
20 mol%
H
N
Cl
Ar
Ar
N
R
3
Ar'
R
+
(Ar)
N
H
COOH
R
O
R
O
3 W blue LED, 65 h
O
P
O
1
: R = 4-FPhSO2-
N
2a
N
Me
O
Me
OH
3 W blue LED, 60 h
3a
: R = H, 91% yield, 90% ee
3h
: R = 3-Br, 91% yield, 90% ee
: R = 2-Br, 63% yield, 89% ee
: R = 4-Me, 77% yield, 93% ee
: R = 3-Me, 95% yield, 90% ee
: R = 4-OMe, 94% yield, 90% ee
NHPMP
2b
: Ar' =
3b
3c
3d
3e
3f
3g
3i
3j
: R = 4-F, 81% yield, 90% ee
: R = 3-F, 80% yield, 90% ee
4
5
3-CF3-4-MeOPh
Ar
C23
R
3k
3l
3m
: R = 2-F, 91% yield, 88% ee
: R= 4-Cl, 69% yield, 90% ee
: R = 3-Cl, 86% yield, 90% ee
O
N
5g
5h
: R = 4-Br, 94% yield, 91% ee
: R = 3-Br, 97% yield, 90% ee
: R = 4-Me, 86% yield, 91% ee
: R = 3-Me, 95% yield, 90% ee
5k
: R = 2-Me, 83% yield, 90% ee
5l
: R = 4-tBu, 96% yield, 86% ee
5a
: R = H, 96% yield, 90% ee
5b
: R = 4-CF3, 84% yield, 90% ee
5c
: R = 4-F, 89% yield, 90% ee
: R = 3-OMe, 78% yield, 89% ee
: R = 2-OMe, 82% yield, 80% ee
Ar'HN
R
a,b
3n
5i
5j
: R = 4-Br, 81% yield, 92% ee
R
Br
NHPMP
Ar
NHPMP
Me
NHPMP
NHPMP
O
5d
: R = 3-F, 93% yield, 92% ee
: R = 4-Cl, 79% yield, 92% ee
: R = 3-Cl, 96% yield, 92% ee
O
O
NHPMP
N
Me
a
5e
5f
O
O
N
O
N
O
N
5m
: R = 3-MeO, 97% yield, 90% ee
D
D
N
R
N
R
Ar'HN
X
R
R
R
D
Ar'HN
O2N
Ar'HN
3o
: Ar = 2-naphthyl
89% yield, 88% ee
3p
3s
3t
: 86% yield
88% ee
: 87% yield
91% ee
Ar'HN
3q
90% eea
3r
D
: 89% yield
: 69% yield
86% eeb
O
N
O
O
D
: Ar = 2-thienyl
O
N
N
93% yield, 90% ee
N
Me
Me
Me
5p
5q
: X = Cl,
Me
Br
PMP
5r
: 64% yield, 95% ee
95% yield, 92% ee
: X = Br,
80% yield, 93% ee
N
PMPN
5n
5o
Br
: 93% yield, 90% ee
: 92% yield, 86% ee
Cl
Cl
1) standard conditions
2) CHCl3, 25 oC, 24 h
O
N
O
standard
conditions
O
O
N
R
Ar'HN
Ar'HN
Ar'HN
Ar'HN
N
R
(one-pot)
N
R
R
X
Me
O
N
1u
1v
3v
: 53% yield
O
N
Me
O
O
3u
: 55% yield
80% ee
N
Me
N
98% eec
Cl
Me
Cl
Me
a
Scheme
2 Substrate scope with respect to 3-benzyl/alkyl-substituted 3-
5s
5t
5u
5v
: 91% yield, 90% ee
5w
: 95% yield, 88% ee
: X = F, 97% yield, 88% ee
: X = Cl, 96% yield, 90% ee
: 75% yield, 87% ee
chlorooxindoles. Reaction conditions: 1 (0.1 mmol) and 2a (0.2 mmol) in a mixed
solvent (3.0 mL, MTBE/THF = 5:1). a C3 was used instead of C1 as the chiral catalyst.
Scheme 3 Substrate scope with respect to 3-aryl-substituted 3-chlorooxindoles.
Reaction conditions: 4 (0.1 mmol) and 2 (0.2 mmol) in a mixed solvent (3.0 mL,
MTBE/THF = 2:1). a T = −60 °C. b On a 1.0 mmol scale, T = −45 °C, 2 X 3 W blue LEDs,
96 h, yield = 97%, ee = 88% (after a single recrystallization, ee = 95%).
b
15 mg of 4 Å molecular sieve (MS) was used as an additive, and 5.0 mL of
c
MTBE/THF (5:1) was used as the solvent. The ee value was determined after a
single recrystallization. Initial data: 87% ee.
Scheme 1). As an analogue of anti-inflammatory I with a methyl suitable N-substituents for 3-phenyl 3-chlorooxindole (4a) and
at the 3-position of the oxindole, product 3q was obtained in glycine (2b), respectively, and in the presence of 1.0 mol% DPZ,
89% yield with 90% ee. Allyl and other alkyl groups containing 20 mol% SPINOL-CPA C23 and 3.0 equiv. of KHCO3 in a mixed
various functional groups, such as alkene, acetal and bromine, solvent (MTBE/THF = 2:1) at −55 °C, product 5a was obtained in
were also tolerated, and products 3r-t were obtained in 69−87% 96% yield with 90% ee (entry 24, Table S2 in the SIand Scheme
yields and 86−91% ee. Notably, the corresponding cyclisation 3). The reaction was found to tolerate a wide range of 3-aryl 3-
product of 3t through the subsequent intramolecular chlorooxindoles regardless of their electronic properties and
substitution was not observed in the reaction system. We the substitution pattern on the 3-aryl rings and oxindole rings,
speculated that this is probably due to the intrinsic difficulty of and corresponding products 5a-w were generated in 64−97%
forming a seven-membered ring. As such, we prepared 1u and yields with 86−93% ees. The transformation to generate 5i was
1v as the substrates to explore the direct synthesis of the key attempted on
a 1.0 mmol scale, and although the
skeletons of horsfiline (III) and analgesic IV. We were pleased to enantioselectivity was slightly decreased, 5i with 95% ee could
find that the transformation of 1u with 2a under a convenient be obtained after performing a single recrystallization. To date,
sequential strategy involving a subsequent one-pot cyclisation chiral 3-aminomethylene-3-substituted oxindoles with various
afforded 3u in 55% yield with 87% ee. After a single structural patterns have been directly synthesized with
recrystallization, its ee was enhanced to 98%. Moreover, the satisfactory results, indicating the high efficacy and good
reaction between 1v and 2a gave product 3v in
a
compatibility of this photoredox asymmetric platform-enabled
straightforward manner with satisfactory results. 4- enantioconvergent substitution approach. The mechanistic
Fluorobenzenesulfonyl as the N-substituent of products could investigations revealed that the enantioselective radical
be readily cleaved using SmI2, and as a paradigm, such a coupling is responsible for the formation of the new C−C bond
modification for 3u afforded the corresponding product in 69% of chiral products (see the SI). Accordingly, a plausible
yield and without compromising ee value (see the SI).
mechanism involving a ternary transition state is proposed
We next tested this substitution strategy with 3-aryl- (Scheme 4).
substituted 3-chlorooxindoles to access another series of
ArHN
COOH
Ar
2
H
H
Ar
O
N
O
important chiral oxindole derivatives, analogues of 5-HT7
ArHN
P
O
O
SPINOL-CPA
redox neutral DPZ
pathway
*DPZ
3/5
O
receptor ligand II (Scheme 1). However, the transformation
between N-4-fluorobenzenesulfonyl-3-phenyl 3-chlorooxindole
and 2a afforded the substitution product in 76% yield but only
8% ee (See entry 1, Table S2 in the SI). The unsatisfactory results
prompted us to carefully re-examine the reaction conditions
(see Table S2 in the SI). Finally, methyl and 3-trifluoro-4-
methoxyphenyl were determined to be the most
R'
radical coupling
R'
Ar
R
N
O
N
R
DPZ
Cl
R'
ternary transition state
O
N
1/4
R
Scheme 4. The proposed mechanism.
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 3
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2005, 436, 1139; (e) L. J. Rono, H. G. Yayla, D. YV.ieWwaArntigcl,eMOn.linFe.
Armstrong, R. R. Knowles, J. Am. ChemD. SOoI:c1.02.1001339,/C139C5C, 1075370345B;
(f) D. Uraguchi, N. Kinoshita, T. Kizu, T. Ooi, J. Am. Chem. Soc.
2015, 137, 13768.
In summary, we have developed an enantioconvergent
substitution of 3-substituted 3-chlorooxindoles with N-aryl
glycines via visible light-driven photoredox asymmetric catalysis.
Under the combinatorial use of DPZ as a photoredox catalyst
and SPINOL-CPA as a Brønsted acid catalyst, the SET redox
transformation could generate prochiral α-amide radicals and
α-aminomethylene radicals, and the two distinct odd-electron
partners could then undergo an enantioselective coupling. A
variety of valuable chiral 3-aminomethylene-3-substituted
oxindoles featuring full carbon quaternary stereocentres were
obtained in high yields with good to excellent
enantioselectivities, and the system showed a broad substrate
scope. Among the obtained products, the direct synthesis of
spiro-five- and -six-membered ring-based products, which are
horsfiline and analgesic therapeutic derivatives, underscores
the high efficiency and good compatibility of this method.
This work was financially supported by NSFC (No. 21672052)
and PhD research foundation of Henan University of Technology
(2019BS003).
9
(a) L. Lin, X. Bai, X. Ye, X. Zhao, C.-H. Tan, Z. Jiang, Angew.
Chem. Int. Ed. 2017, 56, 13842; (b) T. Shao, Y. Yin, R. Lee, X.
Zhao, G. Chai, Z. Jiang, Adv. Synth. Catal. 2018, 360, 1754; (c)
L. Bu, J. Li, Y. Yin, B. Qiao, G. Chai, X. Zhao, Z. Jiang, Chem. Asian
J. 2018, 13, 2382; (d) Y. Liu, X. Liu, J. Li, X. Zhao, B. Qiao, Z.
Jiang, Chem. Sci. 2018, 9, 8094; (e) Y. Yin, Y. Dai, H. Jia, J. Li, L.
Bu, B. Qiao, X. Zhao, Z. Jiang, J. Am. Chem. Soc. 2018, 140,
6083; (f) X. Liu, Y. Liu, G. Chai, B. Qiao, X. Zhao, Z. Jiang, Org.
Lett. 2018, 20, 6298; (g) J. Li, M. Kong, B. Qiao, R. Lee, X. Zhao,
Z. Jiang, Nat. Commun. 2018, 9, 2445; (h) K. Cao, S. M. Tan, R.
Lee, S. Yang, H. Jia, X. Zhao, B. Qiao, Z. Jiang, J. Am. Chem. Soc.
2019, 141, 5437; (i) T. Shao, Y. Li, N. Ma, R. Lee, C. Li, G. Chai,
X. Zhao, B. Qiao, Z. Jiang, iScience 2019, 16, 410; (j) B. Qiao, C.
Li, X. Zhao, Y. Yin, Z. Jiang, Chem. Comm. 2019, 55, 7534; (k)
M. Hou, L. Lin, X. Chai, X. Zhao, B. Qiao, Z. Jiang, Chem. Sci.
2019, 10, 6629.
10 H. in Advanced Free Radical Reactions for Organic Synthesis,
Elsevier Science, Amsterdam, 2004, p. 39.
11 F. Zhou, Y.-L. Liu, J. Zhou, Adv. Synth. Catal. 2010, 352, 1381.
12 (a) A. Rajasekaran, R. Mahesh, P. Parimoo, Indian J. Heterocy.
Chem. 1998, 8, 151; (b) A. A. Kelemen, A. Adam, G. Satala, A.
J. Bojarski, G. M. Keseru, Bioorg. Med. Chem. Lett. 2018, 28,
2418; (c) A. Jossang, P. Jossang, H. Hadi, T. Sevenet, B. Bode,
J. Org. Chem. 1991, 56, 6527; (d) B. M. Trost, M. K. Brennan,
Org. Lett. 2006, 8, 2027; (e) O.-G. Berge, A. Claesson, B.-M.
Swahn, PCT Int. Appl. 2001, WO 2001005790 A1 20010125. (f)
A. Cañas-Rodriguez, P. R. Leeming, J. Med. Chem. 1972, 15,
762; (g) T. Oost, W. Lubisch, W. Wernet, W. Hornberger, L.
Unger, PCT Int. Appl. 2006, WO 2006100082 A2 20060928.
13 (a) X. Tian, K. Jiang, J. Peng, W. Du, Y.-C. Chen, Org. Lett. 2008,
10, 3583; (b) J.-S. Yu, F. Zhou, Y.-L. Liu, J. Zhou, Synlett 2015,
26, 2491; (c) J. Kaur, S. S. Chimni, S. Mahajan, A. Kumar, RSC
Adv. 2015, 5, 52481; (d) S. Nakamura, S. Takahashi, Org. Lett.
2015, 17, 2590; (e) L.-J. Zhou, Y.-C. Zhang, F. Jiang, G. He, J.
Yan, H. Lu, S. Zhang, F. Shi, Adv. Synth. Catal. 2016, 358, 3069;
(f) W. Guo, Y. Liu, C. Li, Org. Lett. 2017, 19, 1044; (g) F. Jiang,
D. Zhao, X. Yang, F.-R. Yuan, G.-J. Mei, F. Shi, ACS Catal. 2017,
7, 6984; (h) G.-J. Me, F. Shi, Chem. Commun. 2018, 54, 6607.
14 (a) G. A. Russell, C. L. Myers, P. Bruni, F. A. Neugebauer, R.
Blankespoor, J. Am. Chem. Soc. 1970, 92, 2762; (b) R. W.
Bennett, D. L. Wharry, T. H. Koch, J. Am. Chem. Soc. 1980, 102,
2345; (c) F. Li, D. Tian, Y. Fan, R. Lee, G. Lu, Y. Yin, B. Qiao, X.
Zhao, Z. Xiao, Z. Jiang, Nat. Commun. 2019, 10, 1774.
Conflicts of interest
There are no conflicts to declare.
Notes and references
1
(a) E. V. Anslyn, D. A. Dougherty, (Eds) in Modern Physical
Organic Chemistry, University Science Books, Sausalito, CA,
2006.
S. R. Hartshorn, in Aliphatic Nucleophilic Subsitution,
Cambridge University Press, London, 1973.
G. C. Fu, ACS Cent. Sci. 2017, 3, 692−700.
2
3
4
(a) S. E. Reisman, A. G. Doyle, E. N. Jacobesen, J. Am. Chem.
Soc. 2008, 130, 7198; (b) S. Ma, X. Han, S. Krishnan, S. C. Virgil,
B. M. Stoltz, Angew. Chem., Int. Ed. 2009, 48, 8037; (c) V. Bhat,
E. R. Welin, X. Gao, B. M. Stoltz, Chem. Rev. 2017, 117, 4528.
For selected reviews see: (a) A. H. Cherney, N. T. Kadunce, S.
E. Reisman, Chem. Rev. 2015, 115, 9587; (b) J. Choi, G. C. Fu,
Science 2017, 356, eaaf7230.
For selected reviews on visible light-driven photoredox
catalysis, see: (a) C. K. Prier, D. A. Rankic, D. W. C. MacMillan,
Chem. Rev. 2013, 113, 5322; (b) M. H. Shaw, J. Twilton, D. W.
C. MacMillan, J. Org. Chem. 2016, 81, 6898; (c) D. Staveness,
R. Bosque, C. R. J. Stephenson, Acc. Chem. Res. 2016, 49, 2295;
(d) B. Qiao, Z. Jiang, ChemPhotoChem, 2018, 2, 703.
(a) D. Staveness, I. Bosque, C. R. J. Stephenson, Acc. Chem.
Res. 2016, 49, 2295; (b) M. Neumann, S. Füldner, B. König, K.
Zeitler, Angew. Chem., Int. Ed. 2011, 50, 951; (c) K. Tahara, Y.
Hisaeda, Green Chem. 2011, 13, 558; (d) T. Maji, A. Karmakar,
O. Reiser, J. Org. Chem. 2011, 76, 736; (e) J. D. Nguyen, E. M.
D’Amato, J. M. R. Narayanam, C. R. J. Stephenson, Nat. Chem.
2012, 4, 854; (f) J. J. Devery III, J. D. Nguyen, C. Dai, C. R. J.
Stephenson, ACS Catal. 2016, 6, 5962; (g) J. Schmidt, J. Choi,
A. T. Liu, M. Slusarczyk, G. C. Fu, Science, 2016, 354, 1265; (h)
Z. Wang, H. Yin, G. C. Fu, Nature 2018, 563, 379.
For selected reviews on photoredox asymmetric catalysis,
see: (a) R. Brimioulle, D. Lenhart, M. M. Maturi, T. Bach,
Angew. Chem. Int. Ed. 2015, 54, 3872; (b) E. Meggers, Chem.
Commun. 2015, 51, 3290; (c) K. L. Skubi, T. R. Blum, T. P. Yoon,
Chem. Rev. 2016, 116, 10035; For selected examples on
enantioselective H-bonding catalysis in photoredox catalysis,
see: (d) A. Bauer, F. Westkämper, S. Grimme, T. Bach, Nature
5
6
15 A. Studer, Chem. Eur. J. 2001, 7, 1159.
(a) E. Arceo, I. D. Jurberg, A. Alvarez-Fernandez, P. Melchiorre,
Nat. Chem. 2013, 5, 750; (b) M. Silvi, C. Verrier, Y. P. Rey, L.
Buzzetti, P. Melchiorre, Nat. Chem. 2017, 9, 868; (c) G.
Filippini, M. Silvi, P. Melchiorre, Angew. Chem. Int. Ed. 2017,
56, 4447; (d) D. Mazzarella, G. E. M. Crisenza, P. Melchiorre, J.
Am. Chem. Soc. 2018, 140, 8439; (e) X. Huang, J. Li, T. Shen, K.
Harms, M. Marchini, P. Ceroni, E. Meggers, Angew. Chem. Int.
Ed. 2018, 57, 5454.
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