Triethylamine → 1,2-Pyrrolidinedicarboxylic acid, 1-(1,1-dimethylethyl) ester, (2S)-

2-tert-Butoxycarbonyloxyimino-2-phenylacetonitrile (1.25 g.) was added to a solution of L-proline (575 mg.) and triethylamine (0.7 ml.) in a mixture of methanol (7.5 ml.), dioxane (2.5 ml.) and water (5.0 ml.) at room temperature, and the mixture was stirred for 1.5 hours at room temperature. The reaction mixture was concentrated under reduced pressure, and to the residue were added benzene and water. After shaking the resultant mixture, the aqueous layer was separated from the mixture, washed with benzene, acidified with hydrochloric acid, and extracted with ethyl acetate. The extract was washed with water, dried over magnesium sulfate and concentrated. To the residue was added a mixture of ether and n-hexane and the precipitated crystals were collected by filtraton and dried to give N-tert-butoxycarbonyl-L-proline (845 mg.), mp 133° to 134° C.

1. concentrationThe reaction mixture was concentrated under reduced pressure
2. additionto the residue were added benzene and water
3. stirringAfter shaking the resultant mixture
4. customthe aqueous layer was separated from the mixture
5. washwashed with benzene
6. extractionextracted with ethyl acetate
7. washThe extract was washed with water
8. dry with materialdried over magnesium sulfate
9. concentrationconcentrated
10. additionTo the residue was added
11. additiona mixture of ether and n-hexane
12. customthe precipitated crystals were collected by filtraton
13. customdried

ORD record

ord-e0c1d05d6b5f47108291469652412eb2

Source dataset

uspto-grants-1977_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04010178