Hydrochloric Acid → 2-{[(Ethylsulfanyl)carbonothioyl]sulfanyl}-2-methylpropanoic acid

This procedure was adapted from the work of You and Oupický. First, ethanethiol (7.21 mL, 0.1 mol), acetone (73 mL), and tricaprylylmethylammonium chloride (1.0 g, 2.5 mmol) were combined and the mixture was cooled on ice under nitrogen. Next, 9 mL of 50% (w/v) of sodium hydroxide was added dropwise. After an additional 20 minutes, carbon disulfide (6.03 mL, 0.1 mol) and acetone (12.6 mL) were combined and added dropwise. Chloroform (12 mL, 0.15 mol) was added, followed by the addition of 80 mL of 50% (w/v) sodium hydroxide over 10 minutes. The yellow-orange mixture was stirred overnight. Water (200 mL) was added, followed by concentrated hydrochloric acid (80 mL) to drop the pH below 1. The mixture was extracted three times into diethyl ether and concentrated to a dark red oil. Crude product was purified via silica gel chromatography (1:1 hexanes:ether) and then distilled to yield 11.0 g of a bright orange, viscous liquid (49% yield). 1H NMR (CDCl3, δ): 1.33 (t, 3H, —CH2CH3), 1.72 (s, 6H, —C(CH3)2COOH), 3.30 (q, 2H, —CH2CH3).

1. temperaturethe mixture was cooled on ice under nitrogen
2. additionadded dropwise
3. extractionThe mixture was extracted three times into diethyl ether
4. concentrationconcentrated to a dark red oil
5. customCrude product was purified via silica gel chromatography (1:1 hexanes:ether)
6. distillationdistilled

ORD record

ord-beb7e365347b42809b49c633c89b0b46

Source dataset

uspto-grants-2016_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09359457B2