Iodine → Methyl 3-iodo-4,5,6,7-tetrahydrobenzo[b]thiophene-2-carboxylate

Temperatur

0 °C

A −78° C. solution of diisopropylamine (23.2 g, 230 mmol) in Tetrahydrofuran (THF) (100 mL) was treated with added n-BuLi (92 mL, 230 mmol) dropwise. The pale yellow solution was stirred at 0° C. for 30 min and recooled to −78° C. To above solution was added the solution of 4,5,6,7-Tetrahydro-benzo[b]thiophene-2-carboxylic acid methyl ester (25 g, 127 mmol) in 20 mL THF dropwise over a period of 5 min. The deep-red solution was stirred at −78° C. for 45 min, the solution of Iodine (48.5 g, 191 mmol) in 20 mL THF was added. The mixture was stirred at −78° C. for 30 min and then warm to room temperature, quenched with saturated aqueous NH4Cl (100 mL) and saturated aqueous Na2S2O3(100 mL). The aqueous layer was extracted with ethyl acetate (150 mL×2). The combined ethyl acetate solution was dried over Na2SO4 and concentrated, which was purified by silica gel chromatography eluted with PE:EtOAc=10:1 to afford title product (15 g, 36% yield). LCMS (m/z) ES+=323 (M+1)

1. customrecooled to −78° C
2. stirringThe deep-red solution was stirred at −78° C. for 45 min
3. stirringThe mixture was stirred at −78° C. for 30 min
4. temperaturewarm to room temperature
5. customquenched with saturated aqueous NH4Cl (100 mL) and saturated aqueous Na2S2O3(100 mL)
6. extractionThe aqueous layer was extracted with ethyl acetate (150 mL×2)
7. dry with materialThe combined ethyl acetate solution was dried over Na2SO4
8. concentrationconcentrated
9. customwhich was purified by silica gel chromatography
10. washeluted with PE

ORD-Eintrag

ord-a5328e43fe8f49a09717c8049f39433f

Quelldatensatz

uspto-grants-2015_04

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09012642B2