Hydrochloric Acid → Methyl tryptophanate hydrochloride

Temperature

20 °C

A 1.2 M solution of HCl in MeOH (440 mL; 0.528 mol) was added to a suspension of L-tryptophan (commercial product) (30.6 g; 150 mmol) in MeOH (70 mL). The resulting clear solution was stirred for 5 days at 20° C. The solution was concentrated (35° C.; 1.3 kPa) to yield a solid which was dissolved in MeOH (10 mL). Et2O (300 mL) was added to the solution and the mixture was vigorously stirred for 1 h. The mixture was filtered and the solid was washed with Et2O (70 mL). The combined solutions were concentrated (35° C.; 1.3 kPa) to a volume of 100 mL and filtered. The solid materials were combined and dried (40° C.; P205; 1.3 kPa) to give as a white solid the desired product (38.5 g; 149.5 mmol). Quantitative yield.

1. concentrationThe solution was concentrated (35° C.; 1.3 kPa)
2. customto yield a solid which
3. stirringthe mixture was vigorously stirred for 1 h
4. filtrationThe mixture was filtered
5. washthe solid was washed with Et2O (70 mL)
6. concentrationThe combined solutions were concentrated (35° C.; 1.3 kPa) to a volume of 100 mL
7. filtrationfiltered
8. customdried (40° C.; P205; 1.3 kPa)

ORD record

ord-5734a32802be4445a50ef87ac719a75c

Source dataset

uspto-grants-2002_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06458337B1