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J.-E. Kang, S. Shin
LETTER
10.3 Hz, 1 H), 4.85 (app t, J = 2.2 Hz, 1 H), 4.42 (app t,
J = 1.8 Hz, 1 H), 2.92 (dd, J = 3.2, 15.0 Hz, 1 H), 2.79 (tdd,
J = 1.4, 10.6, 15.4 Hz, 1 H), 2.39 (s, 3 H). 13C NMR 100
MHz, CDCl3): d = 151.2, 147.1, 139.5, 137.1, 130.7, 129.5,
127.0, 123.4, 95.4, 79.5, 33.9, 22.1.
(8) Typical side products formed at an early stage of the reaction
and showed multiple non-polar spots in TLC, which could
not be unambiguously identified. A similar observation was
made by Gagosz: Gagosz, F. Org. Lett. 2005, 7, 4129.
(9) (a) Kang, J. E.; Lee, E. S.; Park, S. I.; Shin, S. Tetrahedron
Lett. 2005, 46, 7431. (b) Shin, S. Bull. Korean Chem. Soc.
2005, 26, 1925.
Compound 2e: IR: 1772 cm–1. 1H NMR (400 MHz, CDCl3):
d = 4.77 (app t, J = 1.8 Hz, 1 H), 4.36 (app t, J = 1.4 Hz, 1
H), 4.15 (ddd, J = 2.3, 6.9, 10.2 Hz, 1 H), 2.65 (dd, J = 2.9,
15.0 Hz, 1 H), 2.50 (tdd, J = 1.5, 10.3, 15.0 Hz, 1 H), 2.00
(m, 1 H), 1.85–1.07 (m, 10 H). 13C NMR (100 MHz, CDCl3):
d = 151.7, 147.4, 94.9, 82.6, 41.9, 29.1, 28.6, 28.4, 26.7,
26.3, 26.1.
(10) Representative Procedure for the Cyclization of 1d into
2d.
To a solution of 1d (100 mg, 0.384 mmol) in 1,2-dichloro-
ethane (2 mL) at 0 °C, was added Au(PAr3)Cl (Ar = C6F5)
(14.3 mg, 19.2 mmol), followed by AgSbF6 (6.6 mg, 19.2
mmol). Upon addition of AgSbF6, the color of the reaction
mixture immediately turned to orange. The reaction mixture
was kept at 0 °C for 15 h, then was slowly allowed to warm
to r.t. over 5 h. After the reaction was judged to be complete
by TLC, the crude mixture was concentrated to ca. 0.5 mL
and was loaded on silica gel column and was eluted with
EtOAc–hexane (1:4) to obtain 62.8 mg (80%) of 2d as pale
yellow oil, along with 5.7 mg (8%) of hydrolyzed by-
product, 3d.
Compound 2f: IR: 1772 cm–1. 1H NMR (400 MHz, CDCl3):
d = 4.79 (t, J = 1.5 Hz, 1 H), 4.44 (m, 1 H), 4.37 (t, J = 1.5
Hz, 1 H), 2.70 (dd, J = 3.3, 15.4 Hz, 1 H), 2.46 (tdd, J = 1.5,
9.5, 15.0 Hz, 1 H), 1.77 (m, 1 H), 1.75–1.38 (m, 3 H), 0.97
(t, J = 7.3 Hz, 3 H). 13C NMR (100 MHz, CDCl3): d = 151.4,
147.3, 95.0, 78.3, 37.0, 31.5, 18.5, 14.3.
Compound 2g: IR: 1775 cm–1. 1H NMR (400 MHz, CDCl3):
d = 4.78 (t, J = 1.9 Hz, 1 H), 4.37 (t, J = 1.9 Hz, 1 H), 4.13
(ddd, J = 2.9, 6.6, 10.6 Hz, 1 H), 2.66 (dd, J = 3.0, 15.1 Hz,
1 H), 2.48 (tdd, J = 1.5, 10.6, 15.4 Hz, 1 H), 1.93 (m, 1 H),
1.05 (d, J = 7.0 Hz, 3 H), 0.99 (d, J = 7.0 Hz, 3 H). 13C NMR
(100 MHz, CDCl3): d = 151.6, 147.4, 94.9, 83.2, 32.5, 29.0,
18.2, 18.1.
For compound 2a see ref. 2.
Compound 2b: IR: 1777 cm–1. 1H NMR (400 MHz, CDCl3):
d = 7.40 (d, J = 7.9 Hz, 2 H), 7.31 (d, J = 7.8 Hz, 2 H), 5.42
(dd, J = 3.3, 10.7 Hz, 1 H), 4.87 (dd, J = 1.5, 2.2 Hz, 1 H),
4.44 (app t, J = 1.8 Hz, 1 H), 2.93 (dd, J = 3.3, 15.4 Hz, 1 H),
2.76 (tdd, J = 1.5, 10.6, 15.4 Hz, 1 H). 13C NMR (100 MHz,
CDCl3): d = 150.8, 146.7, 135.9, 135.6, 129.9, 127.8, 95.8,
78.7, 33.8. MS (EI): m/z = 181 [M – CO2 + H].
Compound 2h: IR: 1772 cm–1. 1H NMR (400 MHz, CDCl3):
d = 4.77 (dd, J = 0.7, 2.6 Hz, 1 H), 4.39 (dd, J = 1.4, 2.6 Hz,
1 H), 3.90 (dd, J = 4.4, 7.3 Hz, 1 H), 2.68 (m, 1 H), 1.92–1.52
(m, 7 H), 1.21 (d, J = 6.9 Hz, 3 H), 1.45–1.10 (m, 4 H). 13
C
Compound 2c: IR: 1779 cm–1. 1H NMR (400 MHz, CDCl3):
d = 7.33 (t, J = 7.7 Hz, 1 H), 6.94–6.88 (m, 3 H), 5.41 (dd,
J = 3.3, 10.6 Hz, 1 H), 4.86 (app t, J = 1.8 Hz, 1 H), 4.42
(app t, J = 1.9 Hz, 1 H), 3.81 (s, 3 H), 2.93 (dd, J = 3.3, 15.4
Hz, 1 H), 2.79 (tdd, J = 1.9, 10.7, 15.4 Hz, 1 H). 13C NMR
(100 MHz, CDCl3): d = 160.0, 150.4, 146.3, 137.9, 130.0,
117.8, 114.7, 111.2, 94.8, 78.6, 55.3, 33.2.
NMR (100 MHz, CDCl3): d = 156.7, 147.3, 93.7, 87.2, 39.8,
32.0, 29.8, 26.6, 26.3, 14.5.
Compound 2i: IR: 1773 cm–1. 1H NMR (400 MHz, CDCl3):
d = 4.80 (dd, J = 1.1, 2.6 Hz, 1 H), 4.40 (dd, J = 1.5, 2.6 Hz,
1 H), 4.10 (dt, J = 4.0, 8.1 Hz, 1 H), 2.52 (m, 1 H), 1.75–1.47
(m, 3 H), 1.47–1.20 (m, 9 H), 1.23 (d, J = 7.0 Hz, 3 H), 0.88
(t, J = 7.0 Hz, 3 H). 13C NMR (100 MHz, CDCl3): d = 156.6,
147.1, 93.8, 83.3, 34.7, 33.6, 32.4, 29.9, 29.7, 24.8, 23.3,
14.8, 14.3.
Compound 2d: IR: 1780 cm–1. 1H NMR (400 MHz, CDCl3):
d = 7.35–7.25 (m, 1 H), 7.24–7.12 (m, 3 H), 5.40 (dd, J = 3.3,
Synlett 2006, No. 5, 717–720 © Thieme Stuttgart · New York