Hydrochloric Acid → D-Alanine N-(2-methylthio-2,4-dimethylpentan-3-yl)amide

To a solution of 3.2 g. (0.017 mole) N-t-butoxycarbonyl-D-alanine and 2.5 g. (0.017 mole) triethylamine in 100 ml. of tetrahydrofuran at -15° C. was added 1.63 ml. of ethyl chloroformate. After stirring for 15 minutes, 2.49 g. (0.017 mole) 2-methylthio-2,4-dimethyl-3-aminopentane was added and the mixture stirred for one hour. The reaction mixture was diluted with ethyl acetate, washed with water, 5% aqueous citric acid (w/v), sodium bicarbonate solution and brine. The organic phase was evaporated to provide 6.0 g. of residue. This was taken up in 100 ml. methanol, 60 ml. of concentrated hydrochloric acid added and the mixture refluxed for one hour. After evaporation of methanol, the residue was taken up in water, washed with ether, the aqueous phase adjusted to pH 12 with sodium hydroxide and extracted wtih ethyl ether. Evaporation of the extracts gave 3.2 g. (87%) of product as a colorless oil Rf 0.56 (butanol/water/acetic acid-4:1:1 by volume).

1. stirringthe mixture stirred for one hour
2. washwashed with water, 5% aqueous citric acid (w/v), sodium bicarbonate solution and brine
3. customThe organic phase was evaporated
4. customto provide 6.0 g
5. temperaturethe mixture refluxed for one hour
6. customAfter evaporation of methanol
7. washwashed with ether
8. extractionextracted wtih ethyl ether
9. customEvaporation of the extracts
10. customgave 3.2 g

ORD record

ord-9fd7883e5fae4f9e817ec054c57e69a9

Source dataset

uspto-grants-1983_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04411925