Benzylamine → (+/-)-Tert-butyl 3-[3-(benzylamino)-4-chlorophenyl]-2-cyclobutylpropanoate

Temperature

110 °C

Under argon, 848.6 mg (8.83 mmol) of sodium tert-butoxide, 337 mg (0.39 mmol) of tris(dibenzylidenacetone)dipalladium and 183 mg (0.29 mmol) of rac-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl were weighed out into a dry flask, kept under high vacuum for 10 min and then vented with argon. 5 ml of abs. toluene, 0.96 ml (8.83 mmol) of benzylamine and a solution of 2.75 g (7.36 mmol) of (+/−)-tert-butyl 3-(3-bromo-4-chlorophenyl)-2-cyclobutylpropanoate in 5 ml of abs. toluene were added in succession. Three more times, the reaction mixture was evacuated and in each case vented with argon, and the mixture was then stirred at 110° C. for 3 h. After cooling, the reaction mixture was added to saturated aqueous ammonium chloride solution. The mixture was extracted three times with ethyl acetate. The organic phases were combined, dried over magnesium sulphate and concentrated under reduced pressure. The crude product was purified by chromatography on silica gel (mobile phase cyclohexane/dichloromethane 4:1 to 2:1, then pure dichloromethane) This gave 1.95 g of the title compound (65.1% of theory).

1. customThree more times, the reaction mixture was evacuated and in each case
2. temperatureAfter cooling
3. additionthe reaction mixture was added to saturated aqueous ammonium chloride solution
4. extractionThe mixture was extracted three times with ethyl acetate
5. dry with materialdried over magnesium sulphate
6. concentrationconcentrated under reduced pressure
7. customThe crude product was purified by chromatography on silica gel (mobile phase cyclohexane/dichloromethane 4:1 to 2:1

ORD record

ord-52b6d7a13029491f99aeddca84832faf

Source dataset

uspto-grants-2015_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09018414B2