Ethyl chloroformate → Butyramide, 4-piperidino-

To a stirred and cooled (ice bath) solution of 4 parts of 2-(phenylmethoxy)benzoic acid in 90 parts of trichloromethane were added first 1.47 parts of N,N-diethylethanamine and then 1.6 parts of ethyl carbonochloridate at <5° C. After stirring for 1 hour in an ice bath, the thus obtained mixture was added dropwise to a cooled solution of 5.94 parts of trans-4-amino-3-hydroxy-N,N,γ-trimethyl-α,α-diphenyl-1-piperidinebutanamide in 90 parts of trichloromethane at a temperature below 5° C. Upon completion, stirring was continued overnight at room temperature. The organic layer was washed with water, a sodium carbonate solution in water and water, dried, filtered and evaporated. The residue was purified by column chromatography over silica gel using a mixture of trichloromethane and methanol (95:5 by volume) as eluent. The pure fractions were collected and the eluent was evaporated. The residue was C solidified in 2,2'-oxybispropane. The product was filtered off and dried in vacuo at 60° C. yielding 3.7 parts (40.7%) of trans-3-hydroxy-N,N,γ-trimethyl-α,α-diphenyl-4-[[2(piperidinebutanamide: mp 149.0° C. (compound 29).

1. customat <5° C
2. stirringAfter stirring for 1 hour in an ice bath
3. stirringUpon completion, stirring
4. washThe organic layer was washed with water
5. dry with materiala sodium carbonate solution in water and water, dried
6. filtrationfiltered
7. customevaporated
8. customThe residue was purified by column chromatography over silica gel using
9. additiona mixture of trichloromethane and methanol (95:5 by volume) as eluent
10. customThe pure fractions were collected
11. customthe eluent was evaporated
12. filtrationThe product was filtered off
13. customdried in vacuo at 60° C.

ORD record

ord-f1ca9dde5a084954b4d3f4cb966f7288

Source dataset

uspto-grants-1991_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04990521