Methanol → Methyl (2S)-2-amino-3-(4-fluorophenyl)propanoate

Participants

Reaction Conditions

Reaction Steps

1.8 g (10 mmole) of 4-fluorophenylalanine is suspended in 3.0 ml of methanol and cooled to -10° C. under nitrogen and 0.81 ml of thionylchloride added dropwise, keeping the temperature at or below -2° C., and stirred for 1 hour at -5° C to -10° C. About 10 ml of methanol was added and the solution stirred at room temperature overnight. The solution was concentrated in vacuo and the residue triturated with dry ether and filtered to give the hydrochloride salt of 4-fluorophenylalanine methyl ester, m.p. 177.5 to 178° C. The ester hydrochloride is substituted for L-phenylalanine methyl ester hydrochloride in the procedure of Example 6a to yield 6b.

Provenance & Evidence