Triethylamine → (S)-3-(Thiophen-2-ylthio)butanoic acid

To a magnetically-stirred 25 mL round-bottomed flask blanketed with nitrogen was charged 2-mercaptothiophene (0.73 g, 6.29 mmol) in tetrahydrofuran (7 mL, K.F. <0.1 mg/mL) at 25° C. Triethylamine (0.87 mL, 6.29 mmol) was injected and the reaction mixture was stirred for 10 minutes to complete salt formation. To this mixture was added (R)-(+)-β-methyl-β-propiolactone (0.54 g, 6.29 mmol) in one portion and the reaction mixture was stirred at 25° C. for approximately 3 hours. When complete, the mixture was stripped of solvent on a rotary evaporator at 25° C. and diluted with ethyl acetate (10 mL) and water (10 mL). The pH of the mixture was then adjusted to 2.0 with 5N hydrochloric acid and the layers separated. The upper ethyl acetate product layer was dried over sodium sulfate and concentrated to an oil on a rotary evaporator. Silica gel chromatography (10% ethyl acetate/hexanes) afforded 1.19 g of (S)-3-(2-thienylthio)butyric acid (94%).

1. customTo a magnetically-stirred 25 mL round-bottomed flask blanketed with nitrogen
2. stirringthe reaction mixture was stirred at 25° C. for approximately 3 hours
3. customWhen complete, the mixture was stripped of solvent on a rotary evaporator at 25° C.
4. additiondiluted with ethyl acetate (10 mL) and water (10 mL)
5. customthe layers separated
6. dry with materialThe upper ethyl acetate product layer was dried over sodium sulfate
7. concentrationconcentrated to an oil on a rotary evaporator

ORD record

ord-2c953fde28894a809375306370dec01c

Source dataset

uspto-grants-1990_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04968815