Reaktion #80945

Reaktionsgleichung

4-amino-5-chloro-2,3-dihydro-2,2-dimethyl-7-benzofurancarboxylic acid

ethyl chloroformate

ethyl 4-amino-3-methoxy-1-piperidinecarboxylate

→

ethyl cis-4-[(4-amino-5-chloro-2,3-dihydro-2,2-dimethyl-7-benzofuranyl)carbonylamino]-3-methoxy-1-piperidinecarboxylate

Ausbeute 93.2%

Lösungsmittel

N,N-diethylethanamine

trichloromethane

trichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethe temperature below 10° C
2. 2
   workup.STIRRINGStirring
3. 3
   workup.WAITwas continued for 1/2 hour at room temperature
4. 4
   WaschenThe reaction mixture was washed with water, NaOH 5% and water
5. 5
   Sonstigewas then dried
6. 6
   Filtrationfiltered
7. 7
   Sonstigeevaporated
8. 8
   FiltrationThe product was filtered off
9. 9
   Sonstigedried

Vorschrift

To a solution of 8.1 parts of 4-amino-5-chloro-2,3-dihydro-2,2-dimethyl-7-benzofurancarboxylic acid in 218 parts of trichloromethane and 3.43 parts of N,N-diethylethanamine were added dropwise 3.63 parts of ethyl chloroformate, keeping the temperature below 10° C. After stirring for 1/2 hour at 10° C., the whole was added to a solution of 6.26 parts of ethyl 4-amino-3-methoxy-1-piperidinecarboxylate in 145 parts of trichloromethane at 10° C. Stirring was continued for 1/2 hour at room temperature. The reaction mixture was washed with water, NaOH 5% and water and was then dried, filtered and evaporated. The residue was suspended in 2,2'-oxybispropane. The product was filtered off and dried, yielding 12.3 parts (93.2%) of ethyl cis-4-[(4-amino-5-chloro-2,3-dihydro-2,2-dimethyl-7-benzofuranyl)carbonylamino]-3-methoxy-1-piperidinecarboxylate (interm. 1).

Quelle