Metal-Free Aminoiodination of Alkynes Under Visible Light Irradiation for the Construction of a Nitrogen-Containing Eight-Membered Ring System

Article abstract of DOI:10.1002/adsc.202100019

A method for the synthesis of dihydrodibenzo[c,e]azocine derivatives via a regioselective intramolecular aminoiodination of alkynes under visible light irradiation has been developed. This protocol uses a combination of iodine and hypervalent iodine to re

Full text of DOI:10.1002/adsc.202100019

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DOI: 10.1002/adsc.202100019
Metal-Free Aminoiodination of Alkynes Under Visible Light
Irradiation for the Construction of a Nitrogen-Containing Eight-
Membered Ring System
Kyalo Stephen Kanyiva,a,* Tane Marina,b Shun Nishibe,b and Takanori Shibatab,*
a
Global Center of Science and Engineering, School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo,
Shinjuku, Tokyo 169-8555, Japan
E-mail: s.kanyiva@kurenai.waseda.jp
Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo,
b
Shinjuku, Tokyo 169-8555, Japan
E-mail: tshibata@waseda.jp
Manuscript received: January 6, 2021; Revised manuscript received: March 24, 2021;
Version of record online: ■■■, ■■■■
Supporting information for this article is available on the WWW under https://doi.org/10.1002/adsc.202100019
intermolecular aminohalogenation of alkynes under
Abstract: A method for the synthesis of dihydrodi-
benzo[c,e]azocine derivatives via a regioselective
intramolecular aminoiodination of alkynes under
transition metal-free conditions.[4] In contrast, the intra-
molecular aminohalogenation of alkynes is more
studied, and was used to construct a variety of 5- and
visible light irradiation has been developed. This
6-membered heterocycles such as indoles, isoindoli-
protocol uses a combination of iodine and hyper-
nones, isoquinolines, and benzimidazoles.[5] These
valent iodine to realize a sulfonamidyl radical,
aminohalogenation reactions that have been reported to
followed by intramolecular addition to alkyne to
access 5- and 6-membered heterocycles proceed via
form a vinyl radical. Subsequent trapping of iodine
electrophilic cyclization, and no involvement of radical
radical affords an 8-membered heterocycle. Appli-
species was reported. To the best of our knowledge,
cations of the obtained iodinated 8-membered
the synthesis of 8-membered heterocycles via an
heterocycles in the Suzuki-Miyaura coupling and
aminohalogenation reaction has not been reported.
deiodination are also demonstrated.
Medium-sized nitrogen-containing heterocycles are
important intermediates in organic synthesis and have
interesting biological properties.[6] For example, diben-
Keywords: Metal-Free Synthesis; Aminoidodina-
zoazocines such as Imipramine and Desipramine are
tion; Hypervalent Iodine; Alkynes; Dibenzazocines
useful psychotropic drugs. Moreover, the dibenzazo-
cine core is found in alkaloid natural products such as
Apogalanthamine and Buflavine.[6c–d] Medium-sized
The regioselective aminohalogenation of alkynes, ring compounds are mainly synthesized by ring-
alkenes and allenes is a powerful method for synthesiz- expansion reactions, cyclization of acyclic compounds
ing 1,2-aminohalogenated compounds, which are of and ring-closing metathesis.[7] Despite the availability
paramount importance in organic synthesis.[1] A large of these methods, the limited scope of substrates, the
number of reactions using transition-metal catalysts need for expensive reagents and harsh conditions urge
have been reported to access halogen-functionalized the development of further reactions for the synthesis
acyclic amines as well as nitrogen-containing of medium-sized heterocycles.
heterocycles.[2] To avoid the problems associated with
Based on the above background and our continuing
organometallic reagents such as toxicity and difficul- interest in the development of efficient organic
ties in purification, metal-free conditions for amino- reactions using metal-free conditions,[8] as well as the
halogenation have also been developed.[3–5]
synthesis of medium-sized heterocycles,[9] herein we
In comparison to the aminohalogenation of present a regioselective intramolecular reaction for the
alkenes,[3] 1,2-difunctionalization of alkynes via the synthesis of 5,6-dihydrodibenzo[c,e]azocine deriva-
addition of both amine and halogen moieties under tives using iodine and hypervalent iodine under visible
metal-free conditions has been less studied. In fact, light irradiation. We began our studies by evaluating
only a few examples have been reported to achieve the the intramolecular reaction of compound 1a, which
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contains alkynyl and sulfonamide groups, under vari-
ous conditions (Table 1). First, when compound 1a
was treated with iodine (0.5 equiv) and phenyliodine
(III) diacetate (PIDA) (1.2 equiv) in 1,2-dichloroethane
Table 1. Optimization of the Reaction Conditions.[a]
°
(DCE) under 27 W fluorescent light irradiation at 0 C
for 19 h, the desired 8-membered heterocycle 2a was
obtained in 85% isolated yield (entry 1). The structure
of 2a was characterized by NMR and mass spectra,
and the eight-membered ring structure was finally
determined by a single-crystal X-ray diffraction analy-
sis (Figure 1). Although phenyliodine(III) bis(m-chlor-
obenzoate) (PhI(mCBA)2) also gave the desired prod-
uct 2a in 82% yield (entry 2), the desired 8-membered
heterocycle could not be detected when phenyliodine
(III) bis(trifluoroacetate) (PIFA) or Koser’s reagent
(PhI(OH)(OTs)) was used (entries 3, 4). In contrast,
compound 3 was obtained in respective yields of 70
and 73%. A survey of solvents revealed that the
aminoiodination reaction also proceeded in the pres-
ence of THF, MeCN and MeNO2, albeit in lower yields
compared to DCE (entries 5–7 vs 1). The reaction also
proceeded smoothly at rt, or under ceiling light
irradiation to afford 2a in respective yields of 80% and
84% (entries 8, 9). A reaction conducted using N-
iodosuccinimide (NIS) as an iodide source was also
successful and gave dibenzazocine 2a in 65% yield
(entry 10). Notably, control experiments proved that
the presence of visible light, an iodine source, and
hypervalent iodine were crucial for the intramolecular
aminoiodination to proceed (entries 11–13). Based on
these optimization results, the conditions in entry 1
were chosen to examine the substrate scope.
Entry
Hypervalent iodine
Solvent
Yieldb)
1[c]
2
PhI(OAc)2
PhI(mCBA)2
PhI(OCOCF3)2
PhI(OH)(OTs)
PhI(OAc)2
PhI(OAc)2
PhI(OAc)2
PhI(OAc)2
PhI(OAc)2
PhI(OAc)2
PhI(OAc)2
PhI(OAc)2
–
DCE
DCE
DCE
DCE
THF
MeCN
MeNO2
DCE
DCE
DCE
DCE
DCE
DCE
85
82
N.D.
N.D.
23
74
59
80
84
65
0
N.R.
N.R.
3[d]
4[e]
5
6
7
f)
8[g]
9[h]
10[i]
11[j]
12[k]
13[l]
[a]
Reaction conditions: Unless otherwise stated, 1 a
(0.05 mmol), I2 (0.50 equiv.), hypervalent iodine
With the optimized conditions in hand, the scope of
substrates was determined (Table 2). When the N-
protecting group was changed from tosyl to mesitylsul-
fonyl (Mes) or nosyl (Ns) group, cycloadducts 2b and
2c were obtained in lower yields. The aryl group of
the alkynyl moiety could be changed to a phenyl, 4-
fluorophenyl or 4-methoxyphenyl group without much
decrease in yield, as demonstrated in the synthesis of
compounds 2d–2f. Apart from aryl groups, substrates
containing alkynes substituted with n-butyl (1g) and
trimethylsilyl (1h) groups also participated in the
intramolecular aminoiodination reaction to afford
desired 8-membered heterocycles 2g and 2h in
moderate and high yields, respectively. Various elec-
tron-withdrawing and electron-donating groups such as
chloro, methoxy and methyl groups on the tethering
aryl motifs were also tolerated and gave desired
products 2i–2l in 61–94% yields. These results mean
that iodinated 5,6-dihydrodibenzo[c,e]azocines with
various functionalities can be smoothly synthesized
using the present protocol. But terminal alkyne (R3 =
H) was not available and the corresponding cyclo-
adduct was not detected.
°
(1.20 equiv.), dehydrated solvent (3.50 mL) at 0 C for 19 h
under 27 W fluorescent light irradiation.
[b] Isolated yields.
[c] Conducting by 0.10 mmol scale.
[d] Compound 3 was obtained in 70% (NMR yield).
[e] Compound 3 was obtained in 73% (NMR yield).
[f] Using non-dehydrated MeNO2.
[g] At rt.
[h] Ceiling light irradiation.
[i] Using NIS.
[j] Under darkness.
[k] Without I2, 17 h.
[l] 17 h. DCE: 1,2-dichloroethane, MeCN: acetonitrile. N.D.:
Not detected, N.R.: No reaction.
Figure 1. X-ray Structure of 2a (Thermal ellipsoids shown at
To demonstrate the practicality, we conducted the
present intramolecular aminoiodination on a larger
50% probability).
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Table 2. Scope for Aminoiodination of Alkynes: Synthesis of
5,6-Dihydrodibenzo[c,e]azocine.
Scheme 1. Mechanism Study Using TEMPO and BHT.
was also halted. Compound 5, possibly formed by the
reaction of sulfonamidyl radical with BHT, was
obtained in 46% yield after purification.[10] These
observations mean that the present reaction most likely
proceeds via a radical mechanism.
Based on the above observations, previous
studies[11] and our previous report,[8c] a representative
mechanism using substrate 1a is shown in Scheme 2.
The reaction mechanism is initiated by the reaction of
iodine with PhI(OAc)2 to give acetyl hypoiodite
(AcOI). The hypoiodite then reacts with sulfonamide
1a to give an iodosulfonamide intermediate A with the
concomitant formation of AcOH. The nitrogen-iodine
bond of A undergoes light-induced homolytic cleavage
scale using 1a (ca. 0.5 g). Although it required a to form sulfonamidyl radical B, which is stabilized by
longer reaction time, the desired dibenzazocine 2a was the electron-withdrawing sulfonyl group. Next, sulfo-
obtained in good yield along with the recovery of a namidyl radical B adds to the alkynyl motif regiose-
small amount of the substrate (ca. 10%) (Eq. 1).
lectively to afford a vinyl radical species C. Finally,
the vinyl radical C couples with the iodine radical to
give desired iodinated 5,6-dihydrodibenzo[c,e]azocine
2a. Since the present reaction requires light irradiation
and was halted by radical scavengers such as TEMPO
Most previous aminoiodination reactions of alkynes
were demonstrated to proceed via an electrophilic
halogenation mechanism.[5] To gain insight into the
species involved in our intramolecular aminohalogena-
tion reaction, we conducted two reactions using radical
trapping additives (Scheme 1). First, we conducted a
reaction in the presence of 1.0 equivalent of (2,2,6,6-
tetramethylpiperidin-1-yl)oxyl (TEMPO) as a radical
scavenger: formation of the desired product 2a was
completely halted, and imine 4 was obtained in ca.
14% yield as an oxidation product. Next, when the
reaction of 1a was conducted under the optimized
conditions in the presence of 2,6-di-tert-butyl-4-meth-
ylphenol (BHT), formation of the desired product 2a
Scheme 2. Plausible Reaction Mechanism.
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and BHT, a mechanism initiated by activation of the in low yield with low 8-endo/7-exo selectivity (see
alkynyl moiety by acetyl hypoiodite,[12] followed by supporting information in detail), which shows that the
intramolecular sulfonamide addition is not feasible.
biaryl moiety is crucial for the efficient and regiose-
To elucidate the selective 8-endo-dig cyclization lective cyclization.
over 7-exo-dig one, we conducted DFT calculations
Finally, we conducted three synthetic conversions
starting from the nitrogen radical. The geometry using 2a as a representative 5,6-dihydrodibenzo[c,e]
optimizations were carried out at the UωB97X-D[13] azocine. First, the reaction of 2a in the presence of Mg
level of theory with a basis set of 6-31+G(d). Single turnings in refluxed THF/EtOH resulted in removal of
point energy calculations were carried out at the same the tosyl group, reduction of the alkene moiety and
level of theory with 6-311+ +G(2d,2p) and solvation deiodination in a single pot (Eq. 2). As a result,
effects DCE (ɛ=10.125000) using IEFPCM model.[14] dibenzo[c,e]azocine 6, which possess the core structure
According to the energy diagram (Figure 2), the of Apogalanthamine and Buflavine natural products,
activation energy of 8-endo-dig cyclization was was obtained in 61% yield. A palladium-catalyzed
10.2 kcal/mol and that of 7-exo-dig cyclization was removal of the iodine moiety of 2a using boric acid
13.5 kcal/mol. These results mean that the 8-endo-dig proceeded to give compound 7 in 65% yield (Eq. 3).
cyclization preferentially proceeds under the reaction Finally, Suzuki-Miyaura coupling of 2a with 4-meth-
conditions and that the present reaction is kinetically oxyphenylboric acid successfully gave diarylated 5,6-
controlled.
We further investigated the non-covalent interaction
dihydrodibenzo[c,e]azocine 8 in 67% yield (Eq. 4).
in the TS-8-endo by NCI[15] analysis using multiwfn[16]
and visualized by VMD.[17] Figure 3 clearly shows the
steric repulsion around the ortho positions of the biaryl
moiety colored by orange. Moreover, the π–π stacking
between tosyl group and the substituent of alkyne
terminus can be found, which is colored by green.
Actually a control experiment using a monoaryl-
tethered substrate gave the corresponding product, yet
In conclusion, we have demonstrated an intra-
molecular regioselective aminoiodination reaction of
alkynes for the synthesis of a variety of iodinated
dihydrodibenzo[c,e]azocine derivatives under visible
light irradiation using iodine and a hypervalent reagent.
The reaction tolerates a variety of functional groups to
give highly functionalized 8-membered heterocycles,
which are normally difficult to synthesize. We also
elucidated that the reaction proceeded via a radical
mechanism. The preferential 8-endo-dig cyclization
over 7-exo-dig one was supported by DFT calculations.
A few synthetic applications were also demonstrated
and gave the desired products in good yields.
Figure 2. Free Energy Diagram of Radical Cyclization.
Figure 3. Non-Covalent Interactions in the TS-8-endo.
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Chem. 2003, 115, 2508–2511; b) T. Yao, R. C. Larock, J.
Experimental Section
Org. Chem. 2005, 70, 1432–1437; c) D. Fischer, H.
Tomeda, N. K. Pahadi, N. T. Patil, Z. Huo, Y. Yamamoto,
J. Am. Chem. Soc. 2008, 130, 15720–15725; d) S. Mehta,
J. P. Waldo, R. C. Larock, J. Org. Chem. 2009, 74, 1141–
1147; e) X. Zhang, Y. Zhou, H. Wang, D. Guo, D. Ye, Y.
Xu, H. Jiang, H. Liu, Adv. Synth. Catal. 2011, 353,
1429–1437; f) Z. Yuan, R. Cheng, P. Chen, G. Liu, S. H.
Liang, Angew. Chem. Int. Ed. 2016, 55, 11882–11886;
Angew. Chem. 2016, 128, 12061–12065; g) D. Brahm-
chari, A. K. Verma, S. Mehta, J. Org. Chem. 2018, 83,
3339–3347; h) S. Mehta, D. Brahmchari, J. Org. Chem.
2019, 84, 5492–5503.
General procedure for intramolecular aminoiodination:
alkyne 1a (22.6 mg, 0.05 mmol), phenyliodine(III) diacetate
(PhI(OAc)2) (19.4 mg, 0.06 mmol), and iodine (6.4 mg,
0.025 mmol) were placed into a Schlenk tube equipped with a
magnetic stirring bar. The Schlenk tube was evacuated and
backfilled with argon (3×). After the addition of 1,2-dichloro-
ethane (1.75 mL), the Schlenk tube was capped, and the
°
reaction mixture was stirred for 19 h at 0 C under 27 W
fluorescent light irradiation. It was quenched with sat. Na2S2O3
aq. solution and washed with sat. NaHCO3 aq. solution. The
crude material was then purified using preparative TLC
(toluene/ethyl acetate=19/1) to give dibenzazocine 2a.
[6] a) M. Alvarez, A. Joule, in Alkaloids – Chemistry and
Biology, Academic Press: New York, 2001, Vol. 57; b) T.
Okuma, A. Kishimoto, Psychiatry Clin. Neurosci. 1998,
52, 3–12; c) T. Umezawa, Phytochem. Rev. 2003, 2,
371–390; d) P. Appukkuttan, E. V. Eycken, Eur. J. Org.
Chem. 2008, 5867–5886.
Acknowledgements
This work was supported financially by a Grant-in-Aid for
Scientific Research (C) (No. 18 K05114) from JSPS and Asahi
Glass Research Proposal Grant (2019) for KSK. In this study,
S.N. used the techniques of the GRRM program for DFT
calculations supported by MANABIYA system of the Institute for
Chemical Reaction Design and Discovery (ICReDD), Hokkaido
University, which was established by World Premier Interna-
tional Research Initiative (WPI), MEXT, Japan. We also thank
Dr. Natsuhiko Sugimura (Materials Characterization Central
Laboratory, Waseda University) for his support to DFT
calculations.
[7] For selected general reviews, see: a) A. Deiters, S. F.
Martin, Chem. Rev. 2004, 104, 2199–2238; b) K. C.
Majumdar, RSC Adv. 2011, 1, 1152–1170; c) N. Kaur, D.
Kishore, Synth. Commun. 2014, 44, 2577–2614; d) J. R.
Donald, W. P. Unsworth, Chem. Eur. J. 2017, 23, 8780–
8799; e) R. L. Reyes, T. Iwai, M. Sawamura, Chem. Rev.
2020, ASAP, doi.org.10.1021/acs.chemrev.0c00793.
[8] a) T. Otani, A. Tsuyuki, T. Iwachi, S. Someya, K. Tateno,
H. Kawai, T. Saito, K. S. Kanyiva, T. Shibata, Angew.
Chem. Int. Ed. 2017, 56, 3906–3910; Angew. Chem.
2017, 129, 3964–3968; b) K. S. Kanyiva, M. Horiuchi,
T. Shibata, Eur. J. Org. Chem. 2018, 1067–1070; c) K. S.
Kanyiva, M. Tane, T. Shibata, J. Org. Chem. 2019, 84,
12773–12783; d) T. Otani, T. Sasayama, C. Iwashimizu,
K. S. Kanyiva, H. Kawai, T. Shibata, Chem. Commun.
2020, 56, 4484–4487.
References
[1] a) A. Ricci, Amino Group Chemistry: From Synthesis to
the Life Sciences, Wiley-VCH, Weinheim, Germany, 1st
Ed. 2007; b) J. E. G. Kemp, in Comprehensive Organic
Synthesis, Ed. by B. M. Trost and I. Fleming, Pergamon,
Oxford, 1991, Vol. 7, pp. 469–513.
[9] a) Y. Tahara, R. Matsubara, A. Mitake, T. Sato, K. S.
Kanyiva, T. Shibata, Angew. Chem. Int. Ed. 2016, 55,
4552–4556; Angew. Chem. 2016, 128, 4628–4632; b) M.
Ito, R. Kawasaki, K. S. Kanyiva, T. Shibata, Eur. J. Org.
Chem. 2016, 5234–5237; c) A. Mitake, T. Fusamae,
K. S. Kanyiva, T. Shibata, Eur. J. Org. Chem. 2017,
7266–7270; d) M. Ito, D. Inoue, R. Kawasaki, K. S.
Kanyiva, T. Shibata, Heterocycles 2017, 94, 2229–2246;
e) T. Shibata, N. Uno, T. Sasaki, H. Takano, T. Sato,
K. S. Kanyiva, J. Org. Chem. 2018, 83, 3426–3432;
f) M. Ito, D. Inoue, A. Takaki, K. S. Kanyiva, T. Shibata,
Eur. J. Org. Chem. 2018, 4740–4747; g) T. Shibata, T.
Fusamae, H. Takano, N. Sugimura, K. S. Kanyiva, Asian
J. Org. Chem. 2019, 8, 970–977; h) M. Ito, M. Okamura,
K. S. Kanyiva, T. Shibata, Organometallics 2019, 38,
4029–4035; i) M. Ito, D. Inoue, A. Takaki, K. S.
Kanyiva, T. Shibata, Heterocycles 2020, 101, 195–208.
[10] a) K. Sun, Y. Lv, Z. Zhu, L. Zhang, H. Wu, L. Liu, Y.
Jiang, B. Xiao, X. Wang, RSC Adv. 2015, 5, 3094–3097;
b) K. Sun, S. Mu, Z. Liu, R. Feng, Y. Li, K. Pang, B.
Zhang, Org. Biomol. Chem. 2018, 16, 6655–6658; c) C.-
C. Sun, K. Xu, C.-C. Zeng, ACS Sustainable Chem. Eng.
[2] For reviews on aminohalogenation, see: a) G. Li,
S. R. S. S. Kotti, C. Timmons, Eur. J. Org. Chem. 2007,
2745–2758; b) S. R. Chemler, M. T. Bovino, ACS Catal.
2013, 3, 1076–1091.
[3] For recent examples of aminohalogenation alkenes, see:
a) H. Zhang, Y. Song, J. Zhao, J. Zhang, Q. Zhang,
Angew. Chem. Int. Ed. 2014, 53, 11079–11083; Angew.
Chem. 2014, 126, 11259–11263; b) K. Sun, F. Ma, L.
Liu, J. Sun, X. Liu, Y. Wang, Z. Zhang, RSC Adv. 2015,
5, 82492–82495; c) L.-J. Wang, P.-X. Ren, L. Qi, M.
Chen, Y.-L. Lu, J.-Y. Zhao, R. Liu, J.-M. Chen, W. Li,
Org. Lett. 2018, 20, 4411–4415; d) B. Lei, Q. Miao, L.
Ma, R. Fu, F. Hu, N. Ni, Z. Li, Org. Biomol. Chem.
2019, 17, 2126–2133; e) Y. Li, Y. Liang, J. Dong, Y.
Deng, C. Zhao, Z. Su, W. Guan, X. Bi, Q. Liu, J. Fu, J.
Am. Chem. Soc. 2019, 141, 18475–18485.
[4] a) Z. Zhang, L. Chang, S. Wang, H. Wang, Z.-J. Yao,
RSC Adv. 2013, 3, 18446–18452; b) M. Li, H. Yuan, B.
Zhao, F. Liang, J. Zhang, Chem. Commun. 2014, 50,
2360–2363; c) S. Arepally, A. Chamuah, N. Katta, D. S.
Sharada, Eur. J. Org. Chem. 2019, 1542–1547.
[5] a) J. Barluenga, M. Trincado, E. Rubio, J. M. González,
Angew. Chem. Int. Ed. 2003, 42, 2406–2409; Angew.
Adv. Synth. Catal. 2021, 363, 1–7
5
© 2021 Wiley-VCH GmbH
��
These are not the final page numbers!

COMMUNICATIONS
asc.wiley-vch.de
2019, 7, 2255–2261; d) Z. Fang, Y. Feng, H. Dong, D. [13] J.-D. Chai, M. Head-Gordon, Phys. Chem. Chem. Phys.
Li, T. Tang, Chem. Commun. 2016, 52, 11120–11123. 2008, 10, 6615–6620.
[11] a) R. Fan, D. Pu, F. Wen, J. Wu, J. Org. Chem. 2007, 72, [14] a) M. T. Cancès, B. Mennucci, J. Tomasi, J. Chem. Phys.
8994–8997; b) C. Martínez, K. Muñiz, Angew. Chem.
Int. Ed. 2015, 54, 8287–8291; Angew. Chem. 2015, 127,
8405–8409; c) P. Becker, T. Duhamel, C. J. Stein, M.
Reiher, K. Muñiz, Angew. Chem. Int. Ed. 2017, 56,
8004–8008; Angew. Chem. 2017, 129, 8117–8121; d) T.
1997, 107, 3032–3041; b) B. Mennucci, J. Tomasi, J.
Chem. Phys. 1997, 106, 5151–5158; c) B. Mennucci, E.
Cancès, J. Tomasi, J. Phys. Chem. B 1997, 101, 10506–
10517; d) J. Tomasi, B. Mennucci, E. Cancès Mol.
Struct. (Theochem) 1999, 464, 211–226.
Duhamel, C. J. Stein, C. Martínez, M. Reiher, K. Muñiz, [15] E. R. Johnson, S. Keinan, P. Mori-Sánchez, J. Contreras-
ACS Catal. 2018, 8, 3918–3925; e) P. Becker, T.
Duhamel, C. Martínez, K. Muñiz, Angew. Chem. Int. Ed.
García, A. J. Cohen, W. Yang, J. Am. Cem. Soc. 2010,
132, 6498–6506.
2018, 57, 5166–5170; Angew. Chem. 2018, 130, 5262– [16] T. Lu, F. Chen, J. Comput. Chem. 2012, 33, 580–592.
5266.
[17] W. Humphrey, A. Dalke, K. Schulten, J. Mol. Graphics
1996, vol. 14, pp. 33–38.
[12] A mechanism initiated by activation of the alkynyl
moiety by acetyl hypoiodite, D. L. Priebbenow, R. W.
Gable, J. Baell, J. Org. Chem. 2015, 80, 4412–4418.
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Metal-Free Aminoiodination of Alkynes Under Visible Light
Irradiation for the Construction of a Nitrogen-Containing
Eight-Membered Ring System
Adv. Synth. Catal. 2021, 363, 1–7
K. S. Kanyiva*, T. Marina, S. Nishibe, T. Shibata*