Electrochemical Alkoxyhalogenation of Alkenes with Organohalides as the Halide Sources via Dehalogenation

Article abstract of DOI:10.1021/acs.orglett.0c02582

A general, ideal atom utilization electrochemical technology to enable alkene alkoxyhalogenation and organohalide dehalogenation in one pot is presented. This technology is highlighted by convergent strategy integrating several reactions, such as alkene alkoxyhalogenation, organohalide dehalogenation, and dehalogenation deuteration. Experimental data suggest that alkenes have the lowest oxidation potential, which lead to anodic conversion of the C═C bond to the radical cation intermediates, and cathodic transformations of organohalides, including alkyl and aryl halides, as the nucleophilic halogen sources.

Full text of DOI:10.1021/acs.orglett.0c02582

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Letter
Electrochemical Alkoxyhalogenation of Alkenes with Organohalides
as the Halide Sources via Dehalogenation
Ting-Ting Zhang, Mu-Jia Luo,* Yang Li, Ren-Jie Song, and Jin-Heng Li*
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ABSTRACT: A general, ideal atom utilization electrochemical technology to enable alkene alkoxyhalogenation and organohalide
dehalogenation in one pot is presented. This technology is highlighted by convergent strategy integrating several reactions, such as
alkene alkoxyhalogenation, organohalide dehalogenation, and dehalogenation deuteration. Experimental data suggest that alkenes
have the lowest oxidation potential, which lead to anodic conversion of the CC bond to the radical cation intermediates, and
cathodic transformations of organohalides, including alkyl and aryl halides, as the nucleophilic halogen sources.
from the in-situ-formed Mn−X (X = Cl, Br, I) intermediate
(Path I in Scheme 1a),2a−c and the other involves, first, the
formation of molecular dihalogens and then the formation of
the halonium ion (Path II in Scheme 1).2d−g Particularly, the
Lin group has reported a conceptually novel electrochemical
Mn−X intermediate formation strategy to allow the
nucleophilic halogen anions to terminate the process3a−c
However, electrochemical versions that directly added the
halogen anions across the CC double bonds to trigger such
reactions have not been hitherto reported, which might be
attributed to the lower oxidation potential of the previously
reported use of the halogen sources (e.g., inorganic halides, N-
bromosuccinimide, and HBr) than alkenes, thus preferentially
converting into hydrohalides or dihalogen molecules. A new
electrochemical radical cation mode to realize alkene
difunctionalization has been recently reported, wherein the
alkenes had the lowest oxidation potential to make them first
convert to the radical cation intermediates, and then reacted
with two nucleophiles (Path III in Scheme 1).3 However, such
examples are rare and choosing between two such nucleophiles
remains a challenge, especially the first attacking nucleophiles.
At present, only two classes of the first attacking nucleophiles,
including alcohols and organotrifluoroborates, have been
documented in the alkene dialkoxylation: alkoxyamidation
and carbohydroxylation.3 We envisioned that the screening of
new halogen sources, having higher oxidation potential than
rganic electrochemistry has emerged as one of the most
Oimportant and environmentally sustainable tools in
synthesis, where the redox process relies on electrons, not
the conventional chemical oxidants and reductants.1 Recent
significant advances in establishing conceptually novel radical
generation modes have driven a renaissance in electrochemical
synthesis. Among them, the alkene difunctionalization reaction
has been proven to be a mild, efficient, and external-additive-
free (e.g., noble-metal catalysts, oxidants, reductants) alter-
native1h,2−5 to the conventional transition-metal catalysis and
radical processes.6 Typical methods include halofunctionaliza-
tion of alkenes, which is predicated on the use of inorganic
halides, HBr, or N-bromosuccinimide as the halogen sources
(Scheme 1a).1h,2 Generally, these approaches can be divided
into two classes of fashion, according to the mechanisms: one
is direct addition of a radical across the CC double bond,
followed by nucleophilic termination with a halogen anion
Scheme 1. Alkene Difunctionalization Involving
Halogenation
Received: August 3, 2020
https://dx.doi.org/10.1021/acs.orglett.0c02582
© XXXX American Chemical Society
Org. Lett. XXXX, XXX, XXX−XXX
A

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the alkenes, would allow the halogen anions as the first
attacking nucleophiles.
7) and to 88% without Na2HPO4 (Table 1, entry 8), lower
basic Bu4NHSO4 electrolyte diminished the yield of 4 but
n
Herein, we report a new, general convergent electro-
chemistry strategy to realize alkene alkoxyhalogenation6d−g
and organohalide dehalogenation in one pot (Scheme 1b),
which represents an electrochemistry example of alkene
halofunctionalization using organohalides, including alkyl and
aryl halides, as the nucleophilic halogen sources.6 Notable
features of this method are ideal atom utilization, excellent
selectivity, broad substrate scope, and no halogen ambient
pollution by avoiding the release of halide ions from the
carbon−halogen bond cleavage into the environment.7 This
technology also offers efficient access to deuterated com-
pounds by electrochemical dehalogenation deuteration of the
organohalides with deuterated alcohols.8
increased the yield of 5 (Table 1, entry 9). We found that the
nBu4NBr electrolyte was less effective than the stronger basic
nBu4NOH (Table 1, entry 10). Interestingly, product 4 was
n
obtained in 14% yield without 2a when using Bu4NBr as the
electrolyte (Table 1, entry 11). The optimal conditions
accommodated a scaleup to 5 mmol of 1a, giving 4 in 73%
yield (Table 1, entry 12). The use of different electrodes,
including a platinum plate anode, a graphite rod cathode, and a
nickel sheet cathode, showed lower reactivity (entries 23−25;
see Table S1).
With the optimized conditions in hand, the scope of the
electrochemical alkene alkoxybromination protocol, with
respect to olefins 1 and alcohols 3 in the presence of 2a, was
explored (Scheme 2). An array of terminal aryl alkenes bearing
a para-substituent, such as SMe, Me, Ph, F, Cl, Br, and CF3, on
the aryl ring were compatible with the optimized conditions,
giving 7−14 in yields of 55%−85%. The steric hindrance effect
Our studies began with exploitation of the electrochemical
strategy for alkoxybromination of 1-methoxy-4-vinylbenzene
1a with diethyl 2-bromomalonate 2a and MeOH 3a (see Table
1, as well as Table S1 in the Supporting Information). Initial
a
Table 1. Screening of Optimal Reaction Conditions
a
Scheme 2. Variation of the Alkenes (1) with Alcohols (3)
Yield (%)
entry
variation from the standard conditions
4
5
1
2
3
4
5
6
none
0 mA
3 mA
7 mA
57
0
52
0
41
51
40
44
84
88
42
72
14
73
39
40
44
48
5
without Cp2Fe
without Na2HPO4
nBu4NOH, instead of Bu4NBF4
nBu4NOH, instead of Bu4NBF4
nBu4NHSO4, instead of Bu4NBF4
nBu4NBr, instead of Bu4NBF4
nBu4NBr, instead of Bu4NBF4
nBu4NOH, instead of Bu4NBF4
b
n
7
bc
,
n
8
9
<5
65
29
−
n
n
10
11
12
d
e
n
n
6
a
Standard conditions: undivided cell, graphite rod anode, platinum
plate cathode, constant current (5 mA,) 1a (0.2 mmol), 2a (2 equiv),
3a (1 mL), Cp2Fe (3 mol %), nBu4NBF4 (0.1 M), Na2HPO4 (2
equiv), THF (3 mL), argon or air, room temperature, 4 h, 3.73 F/
mol, current efficiency is 77%. Yield of 4 based on 1a and yield of 5
b
based on 2a. Diethyl 2-methoxymalonate 6 was observed by GC-MS
c
d
e
analysis. Without Na2HPO4. Without 2a. 1a (5 mmol) and 36 h.
conditions that employed bromide 2a, MeOH 3a, graphite rod
anode, platinum plate cathode, nBu4NBF4 electrolyte, THF and
5 mA constant current at room temperature to enable
difunctionalization of alkene 1a, affording the desired product
4 in 57% yield and the debromination product 5 in 52% yield
(Table 1, entry 1). Note that the use of either argon or air does
not affect the reaction. A constant current was necessary
because its omission resulted in no reaction, and diminished
yields were obtained when using lower or higher constant
currents (Table 1, entries 2−4). We found that both the Cp2Fe
catalyst and Na2HPO4 base acted as promoters, since the
omission of each only decreased the yields of 4 and 5 (Table 1,
entries 1, 5, and 6). The electrolyte properties could affect the
a
Reaction conditions: undivided cell, graphite rod anode, platinum
plate cathode, constant current (5 mA), 1a (0.2 mmol), 2a (2 equiv),
3a (1 mL), Cp2Fe (3 mol %), Bu4NOH (0.1 M), THF (3 mL), air,
room temperature and 4 h. Product 5 was observed in 5%−20% GC
yield. Only in MeOH (4 mL). 4-(Bromomethyl)-1,2-dihydronaph-
n
n
b
c
chemoselectivity: while strong basic Bu4NOH increased the
yield of 4 to 84% in the presence of Na2HPO4 (Table 1, entry
thalene (32) was observed by GC-MS analysis.
B
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is obvious as alkenes comprising a m-MeO or an o-MeO group
delivered 15 or 16 in diminishing yields. Importantly, the
halogen atoms (e.g., Br, Cl, F) were tolerated (11−13, 19),
which would offer potential for modification at halogenated
positions. Both naphthalene- and heteroaryl-substituted
alkenes were suitable substrates (20 and 21). Notably, 1,3-
diene underwent 1,4-alkoxybromination successfully (22). For
aliphatic alkenes, the reaction efficiently furnished 23 and 24.
Using symmetrical and nonsymmetrical 1,1-disubstituted
alkenes afforded challenging quaternary-carbon-containing
products 25−31 in good to excellent yields. (1-Cyclopropyl-
vinyl)benzene, which is a frequently used radical trapping
reagent, afforded 31 in 82% yield, together with a trace of ring-
opening product 32. Functionalized olefins, including 1,3-
enyne, 1-methylenenaphthalene, and 4′-methylene-1,1′-bi-
(cyclohexane), accommodated the reaction (33−35). Internal
olefins, especially cyclooctene, were competent to access trans-
36−38 as the sole diastereomeric isomers.
Scheme 3. Variation of Halides (2) and Possible
Mechanisms
Next, we became intrigued by the possible modification of
important pharmacophore motifs, such as adamantane,
estrone, and ibuprofen derivatives,9 successfully giving the
corresponding products 39−41 by simultaneous incorporation
of MeO and Br groups. For cholesterol derivatives, the reaction
occurred exclusively at the internal alkene moiety, rather than
the terminal alkene moiety (42). Notably, oxygen- and
nitrogen-possessing alkenes, including pent-4-en-1-ol and
pent-4-en-1-amine, smoothly performed two-component al-
koxybromination, assembling the valuable O- and N-
heterocyclic products 43 and 44. Delightedly, the reaction
was applicable to various alcohols, including primary,
secondary, and tertiary alkyl alcohols, giving 45−48 in good
yields.
Figure S1) than those of both 2-bromomalonate 2a (curve d in
Figure S1) and methanol,4d which had no distinct oxidation
peak in the range of 0−3.5 V. As reported in the literature2−4
and the present results, anodic oxidative cleavage of the π-bond
in alkene 1a might first occur to afford the radical cation
intermediate. The use of Cp2Fe could decrease the oxidation
potential of alkene 1a from 1.68 V to 1.60 V vs Ag/AgCl
(curve c versus curve e in Figure S1), supporting the belief that
Cp2Fe promoted this reaction.
As shown in Scheme 3, organohalides, including alkyl halides
and aryl bromides, were suitable halide sources (49−53), and
primary linear alkyl bromides showed lower reactivity (eqs 1
and 2). Gratifyingly, both alkyl chloride 2j and iodide 2k could
enable alkoxyhalogenation of alkenes (eq S1 in the Supporting
Information). A couple of 1 mmol scale reactions of alkene 1a
were conducted (eq S2 in the Supporting Information). While
strong basic nBu4NOH allowed the conversion of alkene 1a to
4 in 75% yield, together with 7% yield of 49 and 34% yield of
the etherization product 57 (eq S2), which is similar to the
Consequently, we propose that anodic oxidation of alkene
1a first occurs to form the radical cation intermediate A,1h,3
with the aid of Cp2Fe catalyst (Scheme 3). Meanwhile,
bromide 2a may proceed via two processes: one involves a SN2
process, to afford the Br− anion and 6, and the other is the
generation of the radical anion D via the cathodic reduction of
2a, followed by decomposition, to form the Br− anion and the
alkyl radical E (supported by entry 11 in Table 1). Direct
reaction of the Br− anion with the intermediate A occurs to
offer the alkyl radical intermediate B, and then oxidatively
produces the alkyl cation C.4f−i Nucleophilic reaction of the
cation C with 3a affords 4 and H+. The Br− anion may be
oxidatively converted to Br2, which would sequentially perform
direct reaction with intermediate A. In addition, processes that
occur via bromonium cation formation cannot be ruled out.
In summary, we have reported an efficient, ideal atomic
utilization convergent electrochemical technology involving
two key reactions, alkene alkoxyhalogenation and organohalide
dehalogenation, which is the first use of organohalides as the
halogen nucleophiles to initiate alkene electrochemical
difunctionalization. This method is truly general to both
various olefins (e.g., internal/terminal aryl and alkyl alkenes)
and organohalides (e.g., alkyl and aryl halides), which
represents a convergent synthetic technology for achieve
alkene alkoxyhalogenation, dehalogenation, C-halogen deuter-
n
lower yield of 5 (entry 7 in Table 1), weaker basic Bu4NBF4
led to no formation of 57. Treatment of alkene 1a with
bromide 2e in CD3OD gave 49-d1 in 80% yield (eq S3 in the
Supporting Information). Similarly, alkene 1a reacted with
bromide 2a and CD3OD afforded 5-d1 in 57% GC yield (eq
S3), and no intermolecular (kH/kD = 1.0) kinetic isotope effect
(KIE) was observed using a mixture of CD3OD and CH3OH.
These results suggest that the reaction includes a SN2 process
and a radical process. Without constant current, the reaction of
1a with Br2 and MeOH 3a could not occur (see eq S4a in the
Supporting Information), ruling out a background Hunsdieck-
er reaction10 that generates hypobromite and then the Br•
radical. Under a constant current of 5 mA, the reaction with
Br2 led to the formation of 4 in 72% yield (eq S4b in the
Supporting Information), which does not account for the
observed 88% yield using 2a (entry 8 in Table 1). The results
imply that the formation of Br2 is not be the key process, but
the key intermediate derived from bromine is operative.
The cyclic voltammetry (CV) analysis (Figure S1 in the
Supporting Information) indicated that alkene 1a had the
lowest oxidation potential (1.68 V vs Ag/AgCl; curve c in
C
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Letter
(2) (a) Fu, N.; Sauer, G. S.; Lin, S. J. Am. Chem. Soc. 2017, 139,
15548. (b) Fu, N.; Shen, Y.; Allen, A. R.; Song, L.; Ozaki, A.; Lin, S.
ACS Catal. 2019, 9, 746. (c) Lu, L.; Fu, N.; Lin, S. Synlett 2019, 30,
1199. (d) Yan, W.-Q.; Lin, M.-Y.; Little, R. D.; Zeng, C.-C.
Tetrahedron 2017, 73, 764. (e) Wan, C.; Song, R.-J.; Li, J.-H. Org.
Lett. 2019, 21, 2800. (f) Sun, X.; Ma, H.-X.; Mei, T.-S.; Fang, P.; Hu,
Y. Org. Lett. 2019, 21, 3167. (g) Yuan, Y.; Yao, A.; Zheng, Y.; Gao,
M.; Zhou, Z.; Qiao, J.; Hu, J.; Ye, B.; Zhao, J.; Wen, H.; Lei, A.
iScience 2019, 12, 293.
ation, and C-halogen etherization. Notable feature includes the
unique applicability in selective modification of the bioactive
structural systems.
ASSOCIATED CONTENT
* Supporting Information
■
sı
The Supporting Information is available free of charge at
https://pubs.acs.org/doi/10.1021/acs.orglett.0c02582.
(3) For a discussion on dihydroxylation, see: (a) Cai, C.-Y.; Xu, H.-
C. Nat. Commun. 2018, 9, 3551. (b) Zhang, S.; Li, L.; Wu, P.; Gong,
P.; Liu, R.; Xu, K. Adv. Synth. Catal. 2019, 361, 485. For a discussion
on carbohydroxylation, see: (c) Xiong, P.; Long, H.; Song, J.; Wang,
Y.; Li, J.-F.; Xu, H.-C. J. Am. Chem. Soc. 2018, 140, 16387. For a
discussion on aminohydroxylation, see: (d) Zhang, X.; Cui, T.; Zhao,
X.; Liu, P.; Sun, P. Angew. Chem., Int. Ed. 2020, 59, 3465.
(4) For examples on the first radical-addition across the alkenes, see:
(a) Senboku, H.; Komatsu, H.; Fujimura, Y.; Tokuda, M. Synlett
2001, 2001, 0418. (b) Fu, N.; Sauer, G. S.; Saha, A.; Loo, A.; Lin, S.
Science 2017, 357, 575. (c) Fu, N.; Sauer, G. S.; Lin, S. Nat. Protoc.
2018, 13, 1725. (d) Yuan, Y.; Chen, Y.; Tang, S.; Huang, Z.; Lei, A.
Sci. Adv. 2018, 4, No. eaat5312. (e) Siu, J. C.; Sauer, G. S.; Saha, A.;
Experimental details, NMR spectra, and details of the
experiments (PDF)
AUTHOR INFORMATION
Corresponding Authors
■
Mu-Jia Luo − Key Laboratory of Jiangxi Province for Persistent
Pollutants Control and Resources Recycle, Nanchang Hangkong
University, Nanchang 330063, China; State Key Laboratory of
Chemo/Biosensing and Chemometrics, Hunan University,
Changsha 410082, China; Email: luomjchem@163.com
Jin-Heng Li − Key Laboratory of Jiangxi Province for Persistent
Pollutants Control and Resources Recycle, Nanchang Hangkong
University, Nanchang 330063, China; State Key Laboratory of
Chemo/Biosensing and Chemometrics, Hunan University,
Changsha 410082, China; State Key Laboratory of Applied
Organic Chemistry, Lanzhou University, Lanzhou 730000,
China; orcid.org/0000-0001-7215-7152; Email: jhli@
hnu.edu.cn
́
Macey, R. L.; Fu, N.; Chauvire, T.; Lancaster, K. M.; Lin, S. J. Am.
Chem. Soc. 2018, 140, 12511. (f) Zhang, L.; Zhang, G.; Wang, P.; Li,
Y.; Lei, A. Org. Lett. 2018, 20, 7396. (g) Siu, J. C.; Parry, J. B.; Lin, S.
J. Am. Chem. Soc. 2019, 141, 2825. (h) Sun, L.; Yuan, Y.; Yao, M.;
Wang, H.; Wang, D.; Gao, M.; Chen, Y.-H.; Lei, A. Org. Lett. 2019,
21, 1297. (i) Luo, M.-J.; Liu, B.; Li, Y.; Hu, M.; Li, J.-H. Adv. Synth.
Catal. 2019, 361, 1538. (j) Zou, Z.; Zhang, W.; Wang, Y.; Kong, L.;
Karotsis, G.; Wang, Y.; Pan, Y. Org. Lett. 2019, 21, 1857. (k) Kang, J.-
C.; Tu, Y.-Q.; Dong, J.-W.; Chen, C.; Zhou, J.; Ding, T.-M.; Zai, J.-T.;
Chen, Z.-M.; Zhang, S.-Y. Org. Lett. 2019, 21, 2536. (l) Fu, N.; Song,
L.; Liu, J.; Shen, Y.; Siu, J. C.; Lin, S. J. Am. Chem. Soc. 2019, 141,
14480.
Authors
Ting-Ting Zhang − Key Laboratory of Jiangxi Province for
Persistent Pollutants Control and Resources Recycle, Nanchang
Hangkong University, Nanchang 330063, China
Yang Li − Key Laboratory of Jiangxi Province for Persistent
Pollutants Control and Resources Recycle, Nanchang Hangkong
University, Nanchang 330063, China
Ren-Jie Song − Key Laboratory of Jiangxi Province for Persistent
Pollutants Control and Resources Recycle, Nanchang Hangkong
University, Nanchang 330063, China; orcid.org/0000-
0001-8708-7433
(5) For selected reviews on use of the classic transition-metal
catalysis and radical process, see: (a) Patai, S. The Chemistry of
Alkenes; Wiley Interscience: New York, 1964. (b) Wolfe, J. P. Angew.
Chem., Int. Ed. 2012, 51, 10224. (c) Merino, E.; Nevado, C. Chem.
Soc. Rev. 2014, 43, 6598. (d) Wu, K.; Liang, Y.; Jiao, N. Molecules
2016, 21, 352. (e) Song, R.-J.; Liu, Y.; Xie, Y.-X.; Li, J.-H. Synthesis
2015, 47, 1195. (f) Chen, J.-R.; Yu, X.-Y.; Xiao, W.-J. Synthesis 2015,
47, 604. (g) Xu, J.; Song, Q. Youji Huaxue 2016, 36, 1151. (h) Yin,
G.; Mu, X.; Liu, G. Acc. Chem. Res. 2016, 49, 2413. (i) Yang, X.-H.;
Song, R.-J.; Xie, Y.-X.; Li, J.-H. ChemCatChem 2016, 8, 2429.
(j) Studer, A.; Curran, D. P. Angew. Chem., Int. Ed. 2016, 55, 58.
(k) Lan, X.-W.; Wang, N.-X.; Xing, Y. Eur. J. Org. Chem. 2017, 2017,
5821. (l) Giri, R.; KC, S. J. Org. Chem. 2018, 83, 3013. (m) Dhungana,
R. K.; KC, S.; Basnet, P.; Giri, R. Chem. Rec. 2018, 18, 1314. (n) Lin,
J.; Song, R.-J.; Hu, M.; Li, J.-H. Chem. Rec. 2019, 19, 440. (o) Wu, X.;
Wu, S.; Zhu, C. Tetrahedron Lett. 2018, 59, 1328.
Complete contact information is available at:
https://pubs.acs.org/10.1021/acs.orglett.0c02582
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
We thank the National Natural Science Foundation of China
(Nos. 21625203 and 21871126) for financial support.
■
(6) For leading examples on use of organohalides as the halogen
sources beyond halogen atom transfer, see: (a) Candish, L.; Standley,
́
́
E. A.; Gomez-Suarez, A.; Mukherjee, S.; Glorius, F. Chem. - Eur. J.
2016, 22, 9971. (b) Liang, Y.; Lin, F.; Adeli, Y.; Jin, R.; Jiao, N. Angew.
Chem., Int. Ed. 2019, 58, 4566. (c) Zhou, Z.; Yuan, Y.; Cao, Y.; Qiao,
J.; Yao, A.; Zhao, J.; Zuo, W.; Chen, W.; Lei, A. Chin. J. Chem. 2019,
37, 611. (d) Dewkar, G. K.; Narina, S. V.; Sudalai, A. Org. Lett. 2003,
5, 4501. (e) Phukan, P.; Chakraborty, P.; Kataki, D. J. J. Org. Chem.
2006, 71, 7533. (f) Jereb, M.; Zupan, M.; Stavber, S. Green Chem.
2005, 7, 100. (g) Rana, S.; Bag, S.; Patra, T.; Maiti, D. Adv. Synth.
Catal. 2014, 356, 2453.
REFERENCES
■
(1) For selceted reviews, see: (a) Hammerich, O.; Speiser, B.
Organic Electrochemistry: Revised and Expanded, 5th Edition; CRC
Press: Boca Raton, FL, 2015. (b) Yan, M.; Kawamata, Y.; Baran, P. S.
Chem. Rev. 2017, 117, 13230. (c) Tang, S.; Liu, Y.; Lei, A. Chem.
2018, 4, 27. (d) Yang, Q.-L.; Fang, P.; Mei, T.-S. Chin. J. Chem. 2018,
36, 338. (e) Jiang, Y.; Xu, K.; Zeng, C. Chem. Rev. 2018, 118, 4485.
(f) Wang, H.; Gao, X.; Lv, Z.; Abdelilah, T.; Lei, A. Chem. Rev. 2019,
119, 6769. (g) Capaldo, L.; Quadri, L. L.; Ravelli, D. Angew. Chem.,
Int. Ed. 2019, 58, 17508. (h) Sauer, G. S.; Lin, S. ACS Catal. 2018, 8,
5175. (i) Parry, J. B.; Fu, N.; Lin, S. Synlett 2018, 29, 257. (j) Martins,
G. M.; Shirinfar, B.; Hardwick, T.; Ahmed, N. ChemElectroChem
2019, 6, 1300. (k) Mei, H.; Yin, Z.; Liu, J.; Sun, H.; Han, J. Chin. J.
Chem. 2019, 37, 292.
(7) (a) Willett, K. L.; Ulrich, E. M.; Hites, R. A. Environ. Sci. Technol.
1998, 32, 2197. (b) Bolandi, A. S.; Nick, T.; Obare, S. O. Nanotechnol.
Rev. 2012, 1, 147.
(8) For selected examples, see: (a) Mitsudo, K.; Okada, T.;
Shimohara, S.; Mandai, H.; Suga, S. Electrochemistry 2013, 81, 362.
(b) Wang, X.; Zhu, M.-H.; Schuman, D. P.; Zhong, D.; Wang, W.-Y.;
Wu, L.-Y.; Liu, W.; Stoltz, B. M.; Liu, W.-B. J. Am. Chem. Soc. 2018,
D
https://dx.doi.org/10.1021/acs.orglett.0c02582
Org. Lett. XXXX, XXX, XXX−XXX

Organic Letters
pubs.acs.org/OrgLett
Letter
140, 10970. (c) Xia, A.; Xie, X.; Hu, X.; Xu, W.; Liu, Y. J. Org. Chem.
2019, 84, 13841. (d) Schmidt, C. Nat. Biotechnol. 2017, 35, 493.
(9) (a) Teng, X.; Maksimuk, S.; Frommer, S.; Yang, H. Chem. Mater.
2007, 19, 36−41. (b) Elayadi, H.; Lazrek, H. B. Nucleosides,
Nucleotides Nucleic Acids 2015, 34, 433. (c) Alberti, D.; Toppino,
A.; Geninatti Crich, S.; Meraldi, C.; Prandi, C.; Protti, N.; Bortolussi,
S.; Altieri, S.; Aime, S.; Deagostino, A. Org. Biomol. Chem. 2014, 12,
2457. (d) Amir, M.; Kumar, S. Acta Pharm. 2007, 57, 31.
(10) (a) Hunsdiecker, H.; Hunsdiecker, C. Ber. Dtsch. Chem. Ges. B
1942, 75, 291. (b) Johnson, R. G.; Ingham, R. K. Chem. Rev. 1956, 56,
219.
E
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