Potassium thiocyanate → 2H-imidazole-2-thione, 1,3-dihydro-4-(2-methylpropyl)-

Temperature

100 °C

Dissolve 1-amino-4-methyl-2-pentanone hydrochloride (1.4 g, 9.2 mmol) and potassium thiocyanate (1.3 g, 12.9 mmol) in water (3 mL). Stir the solution at 100° C. in a sealed flask for 2 h. Cool the mixture and concentrate in vacuo. Purify the residue by chromatography on silica gel (10 g) eluting with EtOAc to obtain a yellow solid (980 mg, estimated 1:1 product to starting material by NMR). Dissolve the yellow solid (980 mg) in water (2 mL) and concentrated hydrochloric acid (0.5 mL). Add potassium thiocyanate (0.7 g, 7.2 mmol) and heat the mixture at 100° C. for 16 h. Cool the mixture and concentrate in vacuo. Purify the residue by chromatography on silica gel (25 g) eluting with hexane/EtOAc (1:1) to obtain the title compound as a yellow solid (550 mg, 38%). MS (ES+) m/z: 157.2 (M+H)+.

1. temperatureCool the mixture
2. concentrationconcentrate in vacuo
3. customPurify the residue by chromatography on silica gel (10 g)
4. washeluting with EtOAc
5. customto obtain a yellow solid (980 mg, estimated 1:1 product to starting material by NMR)
6. temperatureCool the mixture
7. concentrationconcentrate in vacuo
8. customPurify the residue by chromatography on silica gel (25 g)
9. washeluting with hexane/EtOAc (1:1)

ORD record

ord-78907b4b05964163ab95212f121c5758

Source dataset

uspto-grants-2011_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07994163B2