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

Ethanethiol (7.21 mL, 0.1 mol), acetone (73 mL), and tricaprylylmethylammonium chloride (1.0 g, 2.5 mmol) were combined and cooled on an ice bath under N2. Added 9 mL of 50% (w/v) NaOH to the reaction mixture over 10 minutes. After 20 minutes, carbon disulfide (6.03 mL, 0.1 mol) and acetone (12.6 mL) were combined and added dropwise to the reaction over 30 minutes. Chloroform (12 mL, 0.15 mol) was added, followed by the addition of 80 mL of 50% (w/v) NaOH over 10 minutes. The yellow-orange mixture was stirred overnight. Water (200 mL) was added, followed by concentrated HCl (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. temperaturecooled on an ice bath under N2
2. additionadded dropwise to the reaction over 30 minutes
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-639a2690452f42fa887bf70ef7c6180d

Source dataset

uspto-grants-2014_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08916683B2