Formic Acid → HCID 54360432, compound

Temperature

90 °C

To 110.7 g of above described N-benzyl-isoleucine (0.50 mol) were added 69.0 g formic acid (1.50 mol) and 49.4 g formaldehyde 36.5% in water (0.60 mol) and the clear, colorless reaction mixture was heated under stirring to ˜90° C. for 2 h. The reaction mixture was concentrated by rotary evaporation (60° C./25 mbar) and the residue was triturated under stirring (˜15 min) with 250 ml acetone. After evaporation of the solvent, triturating was repeated twice using a total of 500 ml acetone. Evaporation of the solvent (50° C./10 mbar) gave 129.9 g white, crystalline residue which was stirred with 200 ml acetone for 1 h at RT and 3 h at −20° C. The crystal suspension was filtered, washed with cold acetone and dried (16 h/50° C./10 mbar) affording 103.9 g (88.3%) product as a white, crystalline powder.

1. temperaturethe clear, colorless reaction mixture was heated
2. concentrationThe reaction mixture was concentrated by rotary evaporation (60° C./25 mbar)
3. customthe residue was triturated
4. stirringunder stirring (˜15 min) with 250 ml acetone
5. customAfter evaporation of the solvent
6. customtriturating
7. customEvaporation of the solvent (50° C./10 mbar)
8. customgave 129.9 g white
9. filtrationThe crystal suspension was filtered
10. washwashed with cold acetone
11. customdried (16 h/50° C./10 mbar)

ORD record

ord-8d93c3b6993f4f9092789b86e25287a4

Source dataset

uspto-grants-2007_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07312343B2