Methanol → Methyl L-phenylalaninate hydrochloride

To a 100 ml of reaction flask was added 25 ml of absolute methanol, then cooled down to −10° C. or below using an ice-salt bath, and SOCl2 (7 ml, 96 mmol) was added dropwise slowly under stirring, then reacted for 10 min at a temperature of −10° C. or below, followed by addition of L-phenylalanine (1.65 g, 10 mmol), reacted at a low temperature for 40 min, the ice-salt bath was removed, the obtained solution reacted for 48 h at room temperature, and concentrated under reduced pressure, 15 ml of methanol was added, the result solution was concentrated under reduced pressure for twice. 50 ml of diethyl ether was added, standing, needle crystal was precipitated, filtered and dried, the obtained crude product was recrystallized from methanol-diethyl ether, 2.0 g of white crystal of L-phenylalanine methyl ester hydrochloride was given with a yield of 95%, [α]D25=+37.2° (c=1, CH3CH2OH), m.p.: 155-158° C.

1. customTo a 100 ml of reaction flask
2. temperaturecooled down to −10° C. or below
3. customreacted for 10 min at a temperature of −10° C. or below
4. customreacted at a low temperature for 40 min
5. customthe ice-salt bath was removed
6. customthe obtained solution reacted for 48 h at room temperature
7. concentrationconcentrated under reduced pressure, 15 ml of methanol
8. additionwas added
9. concentrationthe result solution was concentrated under reduced pressure for twice
10. addition50 ml of diethyl ether was added
11. customneedle crystal was precipitated
12. filtrationfiltered
13. customdried
14. customthe obtained crude product
15. customwas recrystallized from methanol-diethyl ether, 2.0 g of white crystal of L-phenylalanine methyl ester hydrochloride

ORD record

ord-a3a718ac11b3433da4238399692662a4

Source dataset

uspto-grants-2016_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09421237B2