反応 #70728

反応方程式

Trimethylboroxine

EtOAc

methyl 2-bromo-6-chloro-1-isopropyl-3-methyl-1H-indole-4-carboxylate

Trimethylboroxine

potassium carbonate

→

methyl 6-chloro-1-isopropyl-2,3-dimethyl-1H-indole-4-carboxylate

収率 81.3%

溶媒

—

hexanes

1,4-Dioxane

反応条件

後処理

1. 1
   濃縮The reaction was concentrated under vacuum
2. 2
   洗浄washed with water
3. 3
   乾燥dried (MgSO4)
4. 4
   ろ過filtered
5. 5
   濃縮concentrated under vacuum
6. 6
   その他Purification by silica gel chromatography (Analogix

実験手順

To a stirred solution of methyl 2-bromo-6-chloro-1-isopropyl-3-methyl-1H-indole-4-carboxylate (0.50 g, 1.451 mmol), Trimethylboroxine (0.30 mL, 2.146 mmol) and potassium carbonate (0.31 g, 2.243 mmol) in 1,4-Dioxane (20 mL) under N2 was added palladium tetrakis (0.18 g, 0.156 mmol). The reaction was heated to 110° C. and stirred for 18 hr. After 3 hr an additional 100 uL Trimethylboroxine was added. The reaction was concentrated under vacuum, taken up in EtOAc, washed with water, dried (MgSO4), filtered and concentrated under vacuum. Purification by silica gel chromatography (Analogix, SF25-60 g, 0 to 10% EtOAc in hexanes) gave the product methyl 6-chloro-1-isopropyl-2,3-dimethyl-1H-indole-4-carboxylate (0.33 g, 1.180 mmol, 81% yield) as a clear thick oil. 1H NMR (400 MHz, DMSO-d6) δ=7.80 (d, J=2.0 Hz, 1H), 7.28 (d, J=1.8 Hz, 1H), 4.81 (dt, J=6.9, 13.9 Hz, 1H), 3.87 (s, 3H), 2.39 (s, 3H), 2.13 (s, 3H), 1.51 (d, J=7.1 Hz, 6H) MS (ES)+m/e 280.1 [M+H]+.

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