Hydrochloric Acid → 2-Bromooctanoic acid

A catalyst solution was prepared by dissolving 59.6 mg (0.045 mmol) of Ru(CF3COO)2 [(S)-MeOBIPHEP-TS-Na] in 20 ml of water in a glove box (O2 content <1 ppm) and was stirred at 20° for 15 min. Then, 1.0 g (4.52 mmol) of (Z)-2-bromo-2-octenoic acid, 30 ml of water and 0.46 g (4.52 mmol) of triethylamine were placed in a 185 ml autoclave and the above-prepared 20 ml of catalyst solution were added. The autoclave was sealed and the hydrogenation was carried out at 20° while stirring and under a constant pressure of 50 bar. After 4 hours the conversion was 100%. The hydrogenation solution was acidified to pH 1 with 1N HCl solution and extracted with diethyl ether. After drying and evaporating the ether extract (40°/20 mbar) the residue was distilled at 115°/0.2 mbar in a bulb tube oven. There was obtained 0.9 g (90%) of (S)-2-bromo-octanoic acid as a colourless oil; chem. purity 98.9 GC area %; 93.0% ee.

1. customA catalyst solution was prepared
2. customThe autoclave was sealed
3. customwas carried out at 20°
4. stirringwhile stirring and under a constant pressure of 50 bar
5. waitAfter 4 hours the conversion was
6. extractionextracted with diethyl ether
7. customAfter drying
8. customevaporating the ether
9. extractionextract (40°/20 mbar) the residue
10. distillationwas distilled at 115°/0.2 mbar in a bulb tube oven

ORD-Eintrag

ord-b24be4a874c840f491b5fdacc2c502ca

Quelldatensatz

uspto-grants-1998_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05852212