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. The mixture was stirred for 1.5 hours at room temperature. The reaction mixture was concentrated under reduced pressure and benzene and water were added to the residue. 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. A mixture of ether and n-hexane was added to the residue and the precipitated crystals were collected by filtration 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 and benzene and water
2. additionwere added to the residue
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. additionA mixture of ether and n-hexane
11. additionwas added to the residue
12. filtrationthe precipitated crystals were collected by filtration
13. customdried

ORD record

ord-5c5a3c5b8afe4a1fa8903fcb95b8e904

Source dataset

uspto-grants-1978_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04083848