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W. Ren et al.
LETTER
(10) Wenkert, E.; Wickberg, B. J. Am. Chem. Soc. 1965, 87,
1580.
(11) Diker, K.; de Maindreville, M. D.; Lévy, J. Tetrahedron Lett.
1995, 36, 2497.
(12) (a) Brooks, D. W.; Lu, L. D. L.; Masamune, S. Angew.
Chem., Int. Ed. Engl. 1979, 18, 72. (b) Gonzalez, G. I.; Zhu,
J. J. Org. Chem. 1999, 64, 914.
(13) (a) Johnson, F. Chem. Rev. 1968, 68, 375. (b) Hoffmann, R.
W. Chem. Rev. 1989, 89, 1841.
(14) Various oxidants have been screened, including: Cu(II) salts
[copper(II) 2-ethylhexanoate, copper(II) chloride, copper(II)
2-pyrazinecarboxylate, copper(II) acetate, copper(II)
trifluoromethanesulfonate, copper(II) acetylacetonate,
copper(II) trifluoroacetylacetonate], Fe(III) salts {iron(III)
chloride, iron(III) acetylacetonate, ferrocenium
hexafluorophosphate, [Fe(DMF)3Cl2][FeCl4]}, Mn(III) salts
[manganese(III) acetate, manganese(III) acetylacetonate],
Co(II) salts [cobalt(II) acetylacetonate, cobalt(II) acetate],
silver(I) trifluoromethanesulfonate, palladium(II) acetate,
titanium tetrachloride, and ceric ammonium nitrate.
(15) Shen, L.; Zhang, M.; Wu, Y.; Qin, Y. Angew. Chem. Int. Ed.
2008, 47, 3618.
133, 19960. (e) West, S. P.; Bisai, A.; Lim, A. D.; Narayan,
R. R.; Sarpong, R. J. Am. Chem. Soc. 2009, 131, 11187.
(19) Procedure for the Preparation of Compound 13
To a solution of methyl malonate 9 (48.0 mg, 0.1 mmol) in
THF (1.0 mL, 0.1 M) was added dropwise LHMDS (0.22
mL, 1.0 M in THF, 0.22 mmol) at –78 °C. After 10 min, the
reaction mixture was warmed to r.t. and a solution of iodine
(52.0 mg, 0.2 mmol) in THF (0.2 mL) was added. The
reaction was stirred at r.t. for 10 min, and then quenched
with Na2S2O3 (aq). The aqueous phase was extracted with
EtOAc. The combined organic layers were dried over
Na2SO4, and the volatiles were removed in vacuo. The
residue was purified by flash column chromatography
(CH2Cl2–acetone = 150:1) to yield 13 as a yellow foam (32.0
mg, 69%). IR (neat): 2925, 2854, 1739, 1454, 1229, 1159
cm–1. 1H NMR (400 MHz, CDCl3): δ = 7.73 (d, J = 8.2 Hz,
2 H), 7.38–7.36 (m, 1 H), 7.29 (d, J = 8.2 Hz, 2 H), 7.13–7.07
(m, 3 H), 4.46 (dd, J = 11.8, 4.2 Hz, 1 H), 3.90 (s, 3 H), 3.76
(ddd, J = 13.4, 4.4, 4.4 Hz, 1 H), 3.61 (s, 3 H), 3.50 (ddd,
J = 13.4, 8.8, 3.6 Hz, 1 H), 2.94–2.89 (m, 1 H), 2.75–2.69 (m,
1 H), 2.66–2.61 (m, 1 H), 2.51–2.43 (m, 1 H), 2.41 (s, 3 H),
2.39–2.32 (m, 1 H), 2.04–1.94 (m, 1 H). 13C NMR (101
MHz, CDCl3): δ = 169.5, 168.0, 143.8, 137.9, 136.7, 131.7,
130.1, 127.7, 127.3, 122.4, 120.7, 118.3, 112.6, 109.9, 68.4,
53.7, 53.2, 53.1, 44.7, 32.1, 27.4, 21.7, 21.3. ESI-HRMS:
m/z [M + H]+ calcd for C25H27N2O6S: 483.1590; found:
483.1598.
(16) Wang, L.; Prabhudas, B.; Clive, D. L. J. J. Am. Chem. Soc.
2009, 131, 6003.
(17) Yamanaka, E.; Nakayama, K.; Yanagishima, N.;
Nagashima, K.; Yamauchi, M.; Sakai, S. Chem. Pharm.
Bull. 1980, 28, 2527.
(18) Selected recent examples of oxidative C–N bond formation:
(a) Maity, S.; Zheng, N. Angew. Chem. Int. Ed. 2012, 51,
9562. (b) Kobayashi, Y.; Kuroda, M.; Toba, N.; Okada, M.;
Tanaka, R.; Kimachi, T. Org. Lett. 2011, 13, 6280. (c) Kim,
H. J.; Kim, J.; Cho, S. H.; Chang, S. J. Am. Chem. Soc. 2011,
133, 16382. (d) Kantak, A. A.; Potavathri, S.; Barham, R.
A.; Romano, K. M.; DeBoef, B. J. Am. Chem. Soc. 2011,
(20) Csákÿ, A. G.; Plumet, J. Chem. Soc. Rev. 2001, 30, 313.
(21) Rathke, M. W.; Lindert, A. J. Am. Chem. Soc. 1971, 93,
4605.
(22) Brocksom, T. J.; Petragnani, N.; Rodrigues, R.; La Scala
Teixeira, H. Synthesis 1975, 396.
(23) Schlitter, E.; Furlenmeier, A. Helv. Chim. Acta 1953, 36,
2017.
(24) Hájíček, J. Collect. Czech. Chem. Commun. 2011, 76, 2023.
Synlett 2013, 24, 1941–1944
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