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ChemComm
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COMMUNICATION
Journal Name
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59; (b) L. J. Legoabe, A. Petzer, and J. DPO. PI:e10tz.1e0r3,V9Bi/eDiwo0AoCrrtCigc0l.e5MO4n2el9indAe.
Chem. Lett., 2014, 24, 2758.
P. S. Poon, A. K. Banerijee, W. J. Vera, H. D. Mora, M. S. Laya,
L. Bedoya, E. V. Cabrera, and C. E. Melean, J. Chem. Res., 2008,
181.
(a) H. Okumoto, T. Jinnai, H. Shimizu, Y. Harada, H. Mishima,
and A. Suzuki, Synlett, 2000, 629; (b) S. B. Park and J. K. Cha,
Org. Lett., 2000, 2, 147; (c) S. Matsumura, Y. Maeda, T.
Nishimura, and S. Uemura, J. Am. Chem. Soc., 2003, 125, 8862.
(a) T. Seiser and N. Cramer, Angew. Chem. Int. Ed., 2008, 47,
9294; (b) A. Yada, S. Fujita, and M. Murakami, J. Am. Chem.
Soc., 2014, 136, 7217.
(a) Y. Yamamoto, T. Arakawa, R. Ogawa, and K. Itoh, J. Am.
Chem. Soc., 2003, 125, 12143; (b) Y. Yamamoto, K. Nishimura,
and M. Shibuya, ACS Catal., 2017, 7, 1101; (c) Y. Yamamoto,
Tetrahedron Lett., 2017, 58, 3787.
The overall process from complex A to I is highly exergonic by
86.6 kcal mol-1, indicating that the cycloisomerization of 1,6-
diyne 1 is thermodynamically favorable.
In conclusion, we have developed the rhodium-catalyzed
cycloisomerization of cyclopropanol-substituted 1,6-diynes,
affording tetralone/exocyclic diene hybrid molecules. We
proposed a plausible reaction mechanism, including the
cyclopropanol-ring opening via
a
rhodacyclopentadiene
intermediate and the E/Z isomerization triggered by
protonation of the lactone carbonyl group, based on the results
of control experiments and DFT calculations. These findings
would lead to the development of novel synthetic methods for
useful helical exocyclic dienes, such as photochromic molecules,
ligands, and organocatalysts.16,17
7
8
(a)
9
(a) K. Tanaka, Synlett, 2007, 1977; (b) T. Shibata and K.
Tsuchikama, Org. Biomol. Chem., 2008, 6, 1317; (c) Y. Shibata
and K. Tanaka, Synthesis, 2012, 44, 323; (d) K. Tanaka, Chem.
Asian J., 2009, 4, 508; (e) M. Amatore and C. Aubert, Eur. J.
Org. Chem., 2015, 265.
OH
O
conditions
14
standard conditions
No reaction
80%
conditions
OH
same as Table 1, entry 2
4
5
10 (a) T. Hashimoto, A. Okabe, T. Mizuno, M. Izawa, and R.
Takeuchi, Tetrahedron, 2014, 70, 8681; (b) T. Hashimoto, S.
Ishii, R. Yano, H. Miura, K. Sakata, and R. Takeuchi, Adv. Synth.
Catal., 2015, 357, 3901.
(b)
(c)
standard conditions
No reaction
MeO
11 In this reaction, any noticeable side products were not
observed by 1H NMR analysis of the crude material. TLC
analysis of the reaction showed tailing stains on the bottom
of the TLC plate, which suggests that intermolecular side
reactions may provide a complex mixture including oligomers.
12 X-ray crystallographic data for compounds 2a, 2e, 2j, 3s, and
7 have been deposited with the Cambridge Crystallographic
codes CCDC2007772, CCDC2007776, CCDC2007773,
CCDC2007774, and CCDC2007775 respectively. For details,
see ESI.
6
OH
HO
Ph
10 mol% [Rh(cod)2]BF4
10 mol% BINAP
Ph
+
CH2Cl2 (0.05 M)
60 ºC, 0.5 h
O
O
O
O
3 equiv
Me
Me
1h
7 90%
X-ray structure of 7
Scheme 3 Control experiments.
13 For selected examples involving transition-metal-mediated
E/Z isomerization reactions, see: (a) I. Ojima, N. Clos, R. J.
Donovan, and P. Ingallina, Organometallics, 1990, 9, 3127; (b)
R. S. Tanke and R. H. Crabtree, J. Am. Chem. Soc., 1990, 112,
7984; (c) S. Xu, K. Chen, H. Chen, J. Yao, and X. Zhu, Chem. Eur.
J., 2014, 20, 16442.
14 We also conducted DFT calculations for the
protodemetalation of complex F without E/Z isomerization
(Figure S11). For details, see ESI.
This research was partially supported by the Platform
Project for Supporting Drug Discovery and Life Science Research
(Basis for Supporting Innovative Drug Discovery and Life Science
Research (BINDS) from AMED under Grant Number
JP20am0101099) and JSPS KAKENHI (Grant Number
JP16KT0051). This work was also supported by the Sasakawa
Scientific Research Grant from The Japan Science Society.
15 Energy-scan for the E/Z-isomerization of an amide-tethered
1,6-diyne substrate suggests that the bond rotation process is
energetically unfavorable compared to the process (F→G)
shown in Fig 1 (Figure S12). For details, see ESI.
Conflicts of interest
There are no conflicts to declare.
16 For selected examples of applications for helical exocyclic
dienes, see: (a) Y. Yokoyama, Chem. Rev., 2000, 100, 1717; (b)
M. Ogasawara, S. Kotani, H. Nakajima, H. Furusho, M.
Miyasaka, Y. Shimoda, W. Y. Wu, M. Sugiura, T. Takahashi, and
M. Nakajima, Angew. Chem. Int. Ed., 2013, 52, 13798; (c) M.
Ogasawara, H. Sasa, H. Hu, Y. Amano, H. Nakajima, N.
Takenaga, K. Nakajima, Y. Kita, T. Takahashi, and T. Dohi, Org.
Lett., 2017, 19, 4102.
Notes and references
1
For selected recent reviews: (a) A. Nikolaev and A. Orellana,
Synthesis, 2016, 48, 1741; (b) G. Fumagalli, S. Stanton, and J.
F. Bower, Chem. Rev., 2017, 117, 9404; (c) L. R. Mills and S. A.
L. Rousseaux, Eur. J. Org. Chem., 2019, 8.
17 Variable-temperature 1H NMR studies on 2j showed that
atropisomerization of 2j is very fast at 22 ºC while the
atropisomers can be distinguished below –60 ºC. For details,
see ESI.
2
(a) J. P. Markham, S. T. Staben, and F. D. Toste, J. Am. Chem.
Soc., 2005, 127, 9708; (b) B. M. Trost, J. Xie, and N. Maulide,
J. Am. Chem. Soc., 2008, 130, 17258; (c) A. S. K. Hashmi, T.
Wang, S. Shi, and M. Rudolph, J. Org. Chem., 2012, 77, 7761;
(d) A. Reding, P. G. Jones, and D. B. Werz, Org. Lett., 2018, 20,
7266.
3
N. Iwasawa and T. Matsuo, Chem. Lett., 1997, 341.
4 | J. Name., 2012, 00, 1-3
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