(R)-1-[3,5-Bis(trifluoromethyl)phenyl]ethylamine HCl

Uses

(R)-1-(3,5-Bis(Trifluoromethyl)phenyl)ethanamine Hydrochloride is a useful reactant for the preparation of palladium complexes with chiral pincer ligands.

Synthesis

The general procedure for the synthesis of (S)-1 -[3,5-bis(trifluoromethyl)phenyl]ethylamine and (R)-1 -[3,5-bis(trifluoromethyl)phenyl]ethylamine, using compound (CAS:384824-41-3) and compound (CAS:511256-29-4) as raw materials, is as follows: 181 mg (0.5 mmol) of the optically active crude product of secondary amine (4a) with 18 mg (0.25 wt%) of 5% palladium/activated carbon (water content: 50 wt%) was added to 2 mL of ethanol. Subsequently, the hydrogen pressure was set to 0.2 MPa and the reaction was stirred at 55°C for 12 hours. Upon completion of the reaction, the reaction solution was filtered through diatomaceous earth, the filtrate was concentrated and dried under vacuum to afford 96 mg of the crude product, i.e., optically active 1-(3,5-bis(trifluoromethyl)phenyl)ethylamine (5a), in 75% yield. The conversion was determined to be 99% by chiral gas chromatography (GC) analysis, the selectivity of the cleavage site (a:b) was 1:99, and the optical purity of the crude product was 76% ee.

References

[1] Patent: US6797842, 2004, B2. Location in patent: Page column 19