F
N. Yamasaki et al.
Letter
Synlett
tion of hydrazine and siloxy group, was also considered.
Thus further study is necessary to prove our proposed
mechanism.
Heathcock, C. H. Org. Lett. 1999, 1, 1475. (d) Myers, A. G.;
Movassaghi, M.; Zheng, B. J. Am. Chem. Soc. 1997, 119, 8572.
(e) Wood, J. L.; Porco, J. A. Jr.; Taunton, J.; Lee, A. Y.; Clardy, J.;
Schreiber, S. L. J. Am. Chem. Soc. 1992, 114, 5898.
(3) Movassaghi, M.; Piizzi, G.; Siegel, D. S.; Piersanti, G. Angew.
Chem. Int. Ed. 2006, 45, 5859.
H
H
(4) Movassaghi, M.; Ahmad, O. K. J. Org. Chem. 2007, 72, 1838.
(5) Kumara Swamy, K. C.; Bhuvan Kumar, N. N.; Balaraman, E.;
Pavan Kumar, K. V. P. Chem. Rev. 2009, 109, 2551.
Ts
H
BocN
Ts
BocN
N
N
20i + 12
(6) Yang, Z.; Kiran Kumar, R.; Liao, P.; Liu, Z.; Li, X.; Bi, X. Chem.
Commun. 2016, 52, 5936.
OTBDPS
21i
24
O
(7) (a) Yamamoto, H.; Ho, E.; Sasaki, I.; Mitsutake, M.; Takagi, Y.;
Imagawa, H.; Nishizawa, M. Eur. J. Org. Chem. 2011, 2417.
(b) Yamamoto, H.; Yamasaki, N.; Yoshidome, S.; Sasaki, I.;
Namba, K.; Imagawa, H.; Nishizawa, M. Synlett 2012, 1069.
(8) (a) Hutchins, R. O.; Kacher, M.; Rua, L. J. Org. Chem. 1975, 40,
923. (b) Kabalka, G. W.; Yang, D. T. C.; Baker, J. D. Jr. J. Org. Chem.
1976, 41, 574. (c) Harapanhalli, R. S. J. Chem. Soc., Perkin Trans. 1
1988, 3149. (d) Chu, M.; Coates, R. M. J. Org. Chem. 1992, 57,
4590. (e) Greco, M. N.; Maryanoff, B. E. Tetrahedron Lett. 1992,
33, 5009. (f) Chai, Y.; Vicic, D. A.; McIntosh, M. C. Org. Lett. 2003,
5, 1039.
O
BocN
N
N
N
H
23i
25
26
Scheme 4 Proposed mechanism from 20i to 23i
In conclusion, we have developed a m-C2B10H11HgCl/
AgOTf-catalyzed carbon–nitrogen bond-forming reaction of
allyl silyl ethers and N-Boc-N′-tosylhydrazine. In all cases,
the reaction proceeded smoothly at 0 °C to furnish the hy-
drazine-substituted products in good yields. The used m-
C2B10H11HgCl was recovered quantitatively. The observation
that the resulting hydrazine-substituted products were ef-
fectively transformed into the corresponding alkenes under
mild acidic conditions highlights the utility of the present
catalytic reaction. We believe the present reaction will fa-
cilitate the synthesis of a variety of alkenes as a Myers-type
reductive deoxygenation.
(9) Iwai, Y.; Ozaki, T.; Takita, R.; Uchiyama, M.; Shimokawa, J.;
Fukuyama, T. Chem. Sci. 2013, 4, 1111.
(10) The structure of the byproduct was indicated in the Supporting
Information.
(11) The reaction of 15a with 12 in CH3CN and toluene at r.t. for
1440 min gave 16 in 23% and 17% yield, respectively.
(12) Nishizawa, M.; Imagawa, H.; Yamamoto, H. Org. Biomol. Chem.
2010, 8, 511.
(13) Yamamoto, H.; Sasaki, I.; Imagawa, H.; Nishizawa, M. Org. Lett.
2007, 9, 1399.
(14) Yamamoto, H.; Sasaki, I.; Hirai, Y.; Namba, K.; Imagawa, H.;
Nishizawa, M. Angew. Chem. Int. Ed. 2009, 48, 1244.
(15) (a) Yamamoto, H.; Sasaki, I.; Shiomi, S.; Yamasaki, N.; Imagawa,
H. Org. Lett. 2012, 14, 2266. (b) Yamamoto, H.; Yamasaki, N.;
Hamauchi, H.; Shiomi, S.; Sasaki, I.; Seyama, K.; Mima, Y.;
Nakano, M.; Kawakami, T.; Miyataka, H.; Kasai, Y.; Imagawa, H.
RSC Adv. 2015, 5, 94737.
Funding Information
(16) Product 16 was obtained as the mixture of rotamers; see Sup-
porting Information.
This study was financially supported by
23790034) from the MEXT (Ministry of Education, Culture, Sports,
Science, and Technology) of the Japanese Government.
a Grant-in-Aid (No.
(17) Preparation
of
0.1
M
CH2Cl2
Solution
of
m-
)(
C2B10H11HgCl/AgOTf
To a suspension of AgOTf (38.5 mg, 0.150 mmol) in CH2Cl2
(1.5 mL) was added m-C2B10H11HgCl (56.9 mg, 0.150 mmol) at
r.t., and the mixture was stirred at r.t. for 30 min.
Acknowledgment
Typical Procedure for the m-C2B10H11HgCl/AgOTf-Catalyzed
Allylic Amination (Table 1, Entry 12)
We are grateful to Dr. Yasuko Okamoto of analysis center in Tokushima
Bunri University for determining the HRMS.
A solution of (E)-tert-butyldiphenyl(undec-6-en-5-yloxy)silane
(15b, 1.08 g, 2.64 mmol) and tert-butyl 2-tosylhydrazine-1-car-
boxylate (12, 755 mg, 3.96 mmol) in CH2Cl2 (8.7 mL) was added
to a dried two-neck flask under an atmosphere of argon. m-
C2B10H11HgCl/AgOTf in 0.1 M CH2Cl2 (1.32 mL) was added drop-
wise to the solution at 0 °C, and the mixture was stirred at 0 °C
for 10 min. The reaction was quenched with sat. NaCl aq, and
the organic phase was separated. The aqueous phase was
extracted with CH2Cl2 (3 ×). The combined organic phase was
dried over MgSO4 and concentrated in vacuo. The residue was
purified by silica gel chromatography (hexane/AcOEt = 20:1 to
4:1) to give 16 (902 mg, 2.06 mmol, 78%) along with m-
C2B10H11HgCl (48.2 mg, 0.127 mmol, 96%).
Supporting Information
Supporting information for this article is available online at
S
u
p
p
ortiInfogrmoaitn
S
u
p
p
ortioInfgrmoaitn
References and Notes
(1) (a) Myers, A. G.; Zheng, B. Tetrahedron Lett. 1996, 37, 4841.
(b) Myers, A. G.; Zheng, B. J. Am. Chem. Soc. 1996, 118, 4492.
(2) For example, see: (a) Siegel, D. S.; Piizzi, G.; Piersanti, G.;
Movassaghi, M. J. Org. Chem. 2009, 74, 9292. (b) Haukaas, M. H.;
O’Doherty, G. A. Org. Lett. 2002, 4, 1771. (c) Ott, G. R.;
Analytical Data for Compound 16
Colorless syrup. FT-IR (neat): 3313, 3238, 3138, 2957, 2929,
© Georg Thieme Verlag Stuttgart · New York — Synlett 2017, 28, A–G