Potassium Fluoride → HCID 19711317, compound

Temperature

70 °C

A mixture of 3.28 g (20.0 mmol) of 5-bromothiazole (for synthesis see H. C. Beyerman, P. H. Berben, J. S. Bontekoe, Rec. Trav. Chim. 1954, 73, 325), 7.43 mL (22.0 mmol) of (1-ethoxyvinyl)tributyltin, and 284 mg (0.404 mmol) of PdCl2 (PPh3)2 in 40 mL of DMF was heated at 70° C. for 30 h. The reaction mixture was cooled to 0° C. and 40 mL of a solution of potassium fluoride in water and 40 mL of diethyl ether were added. After stirring for 40 min the precipitate was faltered off and the aqueous and organic phases separated. The aqueous phase was re-extracted with 4×40 mL of diethyl ether. The combined ether phases were washed with 2×75 mL of water, 1×100 mL of brine, dried (MgSO4) and the solvent removed in vacuo. Flash chromatography (silica gel, 20% ethyl acetate-hexanes) afforded 2.58 g (83%) of the title compound as a yellow oil: 1H NMR (400 MHz, CDCl3) δ8.65 (s, 1H), 7.80 (s, 1H), 4.61 (d, 1H, J=3 Hz), 4.24 (d, 1H, J=3 Hz), 3.91 (q, 2H, J=7 Hz), 13.9 (t, 3H, J=7 Hz).

1. temperatureThe reaction mixture was cooled to 0° C.
2. customthe aqueous and organic phases separated
3. extractionThe aqueous phase was re-extracted with 4×40 mL of diethyl ether
4. washThe combined ether phases were washed with 2×75 mL of water, 1×100 mL of brine
5. dry with materialdried (MgSO4)
6. customthe solvent removed in vacuo

ORD record

ord-6a63dd06413f4d15ad75808a21b91f51

Source dataset

uspto-grants-1998_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05705515