3-Iodothiophene → Butyl 4-(3-thienyl)piperazine-1-carboxylate

Temperatur

100 °C

To a solution of tert-butyl piperazine-1-carboxylate (0.300 g, 1.61 mmol) in 10 mL of toluene under an atmosphere of nitrogen was added 3-iodothiophene (0.390 g, 1.86 mmol), sodium tert-butoxide (0.310 g, 3.22 mmol), tris (dibenzylidenacetone)palladium (0) (0.295 g, 0.322 mmol), and 2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (X-Phos, 0.307 g, 0.644 mmol). The mixture was heated to 100° C. for 18 h, cooled to rt, and treated with water. The solution was extracted 3× with ethyl acetate, and the combined organic solution was washed with brine, dried over sodium sulfate, filtered, and concentrated in vacuo. The resultant residue was purified via silica gel chromatography, eluting with 0-70% ethyl acetate, to provide text-butyl 4-(3-thienyl)piperazine-1-carboxylate that gave a proton NMR spectra consistent with theory.

1. temperaturecooled to rt
2. extractionThe solution was extracted 3× with ethyl acetate
3. washthe combined organic solution was washed with brine
4. dry with materialdried over sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customThe resultant residue was purified via silica gel chromatography
8. washeluting with 0-70% ethyl acetate

ORD-Eintrag

ord-614555e96b724d83b2a7fb7b81e7bf0b

Quelldatensatz

uspto-grants-2013_02

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08383638B2