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P. Gu et al.
LETTER
(2.7 mg, 0.003 mmol) in CH2Cl2 (1.0 mL), and the mixture
was stirred at 10–15 °C for 30 min. 2 M aq HCl (0.5 mL) was
added, and the mixture was kept for another 45 min. H2O
(5 mL) was then added, and the mixture was extracted with
CH2Cl2 (10 mL). The extracts were washed with H2O (10
mL), and the organic phases were combined, dried
(Na2SO4), and concentrated. The residue was purified by
flash chromatography to give a slightly yellow oil; yield: 88
mg (99%). Rf = 0.52 (EtOAc–PE, 1:10); 1H NMR (400
MHz, CDCl3): δ = 1.43 (t, J = 7.2 Hz, 3 H), 4.46 (q, J = 7.2
Hz, 2 H), 7.50–7.54 (m, 2 H), 7.64–7.69 (m, 1 H), 8.00–8.03
(m, 2 H); 13C NMR (100 MHz, CDCl3): δ = 14.1, 62.3, 128.9
(2 C), 130.0 (2 C), 132.4, 134.9, 163.8, 186.4.
References
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Synlett 2014, 25, 535–538
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