反応 #46512

反応方程式

HCl

SnCl4

2-methylbenzo[b]thiophene

dichloromethyl methyl ether

→

title compound

収率 98.2%

2-Methylbenzo[b]thiophene-3-carboxaldehyde

収率 98.2%

溶媒

CH2Cl2

反応条件

後処理

1. 1
   workup.ADDITIONwas poured onto ice water (200 mL)
2. 2
   workup.STIRRINGstirred until the suspension
3. 3
   workup.DISSOLUTIONdissolved
4. 4
   その他The organic phase was separated
5. 5
   乾燥dried (MgSO4)
6. 6
   濃縮concentrated under vacuum
7. 7
   その他Purification by flash chromatography on silica gel (10% ethyl acetate/hexane)

実験手順

SnCl4 (20 mL, 67 mmole) was added over 5 min to a stirred solution of 2-methylbenzo[b]thiophene (5.0 g, 33.7 mmole) in CH2Cl2 (75 mL) at 0° C. under argon. After 15 minutes, dichloromethyl methyl ether (3.7 mL, 41 mmole) was added. The reaction became a yellowish colored suspension. The reaction was allowed to warm to RT and stirred for 16 h, then was poured onto ice water (200 mL). The aqueous mixture was acidified with 1.0 N HCl (100 mL) and stirred until the suspension dissolved. The organic phase was separated, dried (MgSO4), and concentrated under vacuum. Purification by flash chromatography on silica gel (10% ethyl acetate/hexane) gave the title compound (5.83 g, 98%) as a white crystalline solid: 1H NMR (400 MHz, CDCl3) δ 10.38 (s, 1 H), 8.61 (d, J=8.1 Hz, 1 H), 7.77 (d, J=8.0 Hz, 1 H), 7.48 (t, 1 H), 7.39 (t, 1 H), 2.93 (s, 3 H).

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