2,3-Dihydroxybutanedioic Acid → HCID 58247963, compound

Temperature

0 °C

2.18 g (7.92 mmol) of 2,2,2-trifluoro-1-[3-fluoro-5-(trifluoromethyl)phenyl]ethanone oxime were stirred in 35.4 ml of isopropyl ether, and admixed with 3.54 g (93.35 mmol) of lithium aluminium hydride in portions [cf. also synthesis of aryltrifluoroethylamines: DE 2723464, 1977)]. Thereafter, the reaction mixture was stirred at reflux temperature for approx. 3 hours. For workup, the reaction mixture was cooled to 0° C. and admixed cautiously with saturated tartaric acid solution, in order to destroy excess lithium aluminium hydride. After the vigorous evolution of gas had ended, the mixture was admixed with 2N sodium hydroxide solution (alkaline) and the organic phase was removed. The aqueous phase was extracted twice more with isopropyl ether. Thereafter, the combined phases were dried over magnesium sulphate and concentrated under reduced pressure at 40° C. (not less than 50 mbar). This gave 1.55 g (71.7% of theory) of α,3-bis(trifluoromethyl)-5-fluorobenzenemethanamine, which was used for subsequent reactions without further purification.

1. temperatureat reflux temperature for approx. 3 hours
2. customto destroy excess lithium aluminium hydride
3. customthe organic phase was removed
4. extractionThe aqueous phase was extracted twice more with isopropyl ether
5. dry with materialThereafter, the combined phases were dried over magnesium sulphate
6. concentrationconcentrated under reduced pressure at 40° C. (not less than 50 mbar)
7. customThis gave 1.55 g (71.7% of theory) of α,3-bis(trifluoromethyl)-5-fluorobenzenemethanamine, which was used for subsequent reactions without further purification

ORD record

ord-29ddd39b917a42d09911727983ab4875

Source dataset

uspto-grants-2014_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08889878B2