Potassium Hydroxide → HCID 54388166, compound

Participants

Reaction Steps

5 g of 3,4-dichlorophenylsulphonyl chloride are introduced, with stirring, into a mixture of 3,8 g of ethyl O-methyltyrosinate in 35 ml of CH2Cl2 and 50 ml of a saturated aqueous potassium carbonate solution. After one night, the solid is removed, the organic phase separated and the aqueous phase reextracted with CH2Cl2. The dried organic phases are concentrated and the residue is chromatographed on a silica column, eluting with a mixture of CH2Cl2 and CH3OH (95/5-V/V). 6.8 g of racemic ethyl N-(3,4-dichlorophenylsulphonyl)-O-methyltyrosinate are obtained, which product melts at 99° C. This ester is hydrolysed in 100 ml of C2H5OH containing 9.5 ml of a 5N aqueous KOH solution to give, after acidification, 5.5 g of the corresponding acid which melts at 183° C.

Provenance & Evidence