反応 #577224

反応方程式

Methyl bromoacetate

21

2-(6-Hydroxy-3-oxo-3H-xanthen-9-yl)-benzoic acid 2-propenyl ester

K2CO3

phenylsilane

→

22

収率 62.0%

(6′-hydroxy-3-oxospiro[isobenzofuran-1(3H), 9′-[9H]xanthen]-3′-yl)oxy-acetic acid methyl ester

収率 62.0%

溶媒

DMF

反応条件

後処理

1. 1
   濃縮The mixture was concentrated
2. 2
   workup.ADDITIONdiluted with ethyl acetate
3. 3
   洗浄washed with 10% NaHCO3, brine
4. 4
   乾燥dried with anhydrous Na2SO4
5. 5
   その他evaporated
6. 6
   workup.DISSOLUTIONThe residue was dissolved in dry DCM (25 mL)
7. 7
   workup.STIRRINGThe mixture was stirred for 2 h at room temperature
8. 8
   濃縮concentrated
9. 9
   その他The residue was purified by column chromatography (ethyl acetate/hexane=1:1)

実験手順

Methyl bromoacetate (0.25 mL, 2.65 mmol) was added dropwise to a stirred mixture of 21 (0.33 g, 0.89 mmol) and K2CO3 (0.36 g, 2.65 mmol) in dry DMF (20 mL) under argon. The resulting mixture was stirred for 4 h at 90° C. The mixture was concentrated, diluted with ethyl acetate, washed with 10% NaHCO3, brine, dried with anhydrous Na2SO4, and evaporated. The residue was dissolved in dry DCM (25 mL). Tetrakis(triphenylphosphine) palladium(0) (58 mg, 0.05 mmol) and phenylsilane (1.1 mL, 8.90 mmol) were added. The mixture was stirred for 2 h at room temperature and concentrated. The residue was purified by column chromatography (ethyl acetate/hexane=1:1) to give 22 as a yellow solid (0.22 g, 62%). TLC (ethyl acetate/hexane, 3:1): Rf=0.5. mp 236° C. 1H NMR (CDCl3/CD3OD, 500 MHz) δ 3.76 (s, 3H, CO2CH3), 4.69 (s, 2H, CH2), 6.68 (m, 6H), 7.19 (d, J=7.5 Hz, 1H), 7.66 (t, J=7.5 Hz, 1H), 7.71 (t, J=7.5 Hz, 1H), 8.01 (d, J=7.5 Hz, 1H). 13C NMR (CDCl3/CD3OD, 125 MHz) δ 52.33, 65.18, 101.86, 102.77, 109.84, 111.55, 112.37, 112.52, 124.05, 124.87, 126.67, 129.00, 129.24, 129.80, 135.21, 152.47, 152.56, 152.94, 159.34, 169.21, 170.15, 171.36, 172.03. ESIMS calcd for C23H17O7 [M+H]+ 405.1. Found 405.2.

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