Dicyclohexylcarbodiimide → 4-methyl-2-oxo-N-(2-oxo-2-phenylethyl)pentanamide

A solution of dicyclohexylcarbodiimide (DCC) (157 g) in dichloromethane (200 ml) was added dropwise over 2 hours to an efficiently stirred mixture of powdered sodium 4-methyl-2-oxopentanoate (115.5 g), 2-aminoacetophenone hydrochloride (130.4 g) and HOBT (103 g) in dichloromethane (1 liter). The mixture was stirred overnight and the insoluble dicyclohexylurea removed by filtration. The filtrate was concentrated and the residue redissolved in dichloromethane (500 ml). The mixture was filtered to remove a further quantity of dicyclohexylurea, and the filtrate was washed with saturated sodium hydrogen carbonate solution (500 ml), water (500 ml) and saturated sodium chloride solution (500 ml). The organic phase was dried and concentrated to give 4-methyl-2-oxo-N-(2-oxo-2-phenylethyl)pentanamide (C), as a foam (183.6 g), which was used without further purification; NMR (CDCl3) : 1.0 (d, 6H), 2.2 (m, 1H), 2.8 (d, 2H), 4.75 (d, 2H), 7.4-7.7 (m, 3H), 7.9 (br, 1H), 8.0 (m, 2H).

1. customthe insoluble dicyclohexylurea removed by filtration
2. concentrationThe filtrate was concentrated
3. dissolutionthe residue redissolved in dichloromethane (500 ml)
4. filtrationThe mixture was filtered
5. customto remove a further quantity of dicyclohexylurea
6. washthe filtrate was washed with saturated sodium hydrogen carbonate solution (500 ml), water (500 ml) and saturated sodium chloride solution (500 ml)
7. customThe organic phase was dried
8. concentrationconcentrated

ORD record

ord-e843ef30dbe248978321e619f17a5b73

Source dataset

uspto-grants-1992_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05091425