Potassium Carbonate → 4-(3-Dimethylaminomethylene-thioureidomethyl)-piperidine-1-carboxylic acid tert-butyl ester

A solution of 17.7 g (82.6 mmol) 4-aminomethyl-piperidine-1-carboxylic acid tert-butyl ester (commercially available) in 150 ml THF was treated with 11.1 ml (82.6 mmol) benzoyl isothiocyanate and stirred for 1 h at room temperature. After evaporation of the solvents the residue was taken up in 100 ml MeOH and treated with 34.2 g (248 mmol) potassium carbonate in 100 ml water. After stirring the mixture for 16 h at room temperature all volatiles were removed and the residue extracted with ethyl acetate. The combined organic layers were washed with saturated NaHCO3 solution and dried with MgSO4. After evaporation of the volatiles 88.1 ml (661 mmol) N,N-dimethylformamide dimethyl acetal was added and the mixture was heated to 110° C. for 16 h. The precipitate was filtered off, washed with n-hexane and dried to yield 21.5 g (79%) of the title compound as pink amorphous solid.

1. customAfter evaporation of the solvents the residue
2. stirringAfter stirring the mixture for 16 h at room temperature all volatiles
3. customwere removed
4. extractionthe residue extracted with ethyl acetate
5. washThe combined organic layers were washed with saturated NaHCO3 solution
6. dry with materialdried with MgSO4
7. additionwas added
8. temperaturethe mixture was heated to 110° C. for 16 h
9. filtrationThe precipitate was filtered off
10. washwashed with n-hexane
11. customdried

ORD record

ord-019b1077bec14d9b827da135577f82bf

Source dataset

uspto-grants-2007_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07265109B2