Triethylamine → 4-[2-(1,1-Dioxo-isothiazolidin-2-yl)-ethyl]-piperazine-1-carboxylic acid tert-butyl ester

To a stirred solution of 1-Boc-4-(2-aminoethyl)-piperazine (1.26 g, 6.8 mmol) and triethylamine (1 mL) in THF (10 ML), 3-chloro-propylsulfonyl chloride (Aldrich, 0.68 mL, 6.94 mmol) was added slowly at room temperature. The mixture was stirred for 30 minutes at and the reaction was quenched with water. The new mixture was extracted with ethyl acetate and the extracts were combined and dried (Na2SO4). The solution was concentrated and the residue was dissolved in THF (20 mL) and Cs2CO3 (500 mg), NaI (80 mg) were added and the mixture was stirred at reflux overnight. The mixture was cooled to room temperature and poured into water. The new mixture was extracted with ethyl acetate (3×15 mL) and the extracts were combined and dried (Na2SO4). Removal of the solvent on a rotary evaporator gave a solid. 2.01 g.

1. customwas quenched with water
2. extractionThe new mixture was extracted with ethyl acetate
3. dry with materialdried (Na2SO4)
4. concentrationThe solution was concentrated
5. dissolutionthe residue was dissolved in THF (20 mL)
6. additionCs2CO3 (500 mg), NaI (80 mg) were added
7. stirringthe mixture was stirred
8. temperatureat reflux overnight
9. additionpoured into water
10. extractionThe new mixture was extracted with ethyl acetate (3×15 mL)
11. dry with materialdried (Na2SO4)
12. customRemoval of the solvent
13. customon a rotary evaporator
14. customgave a solid

ORD record

ord-1022d81cd44f481baa69582f04df677c

Source dataset

uspto-grants-2009_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07495007B2