Benzylamine → (+/-)-Tert-butyl 2-[3-(benzylamino)-4-chlorobenzyl]-2-methylbutanoate

Participants

Reaction Conditions

Reaction Steps

Under argon, 1.59 g (16.6 mmol) of sodium tert-butoxide were weighed out into a dry flask, and 34.6 ml of abs. toluene were added. 5.0 g (13.8 mmol) of (+/−)-tert-butyl-2-(3-bromo-4-chlorobenzyl)-2-methylbutanoate, 1.8 ml (16.6 mmol) of benzylamine, 633 mg (0.69 mmol) of tris(dibenzylidenacetone)dipalladium and 344 mg (0.55 mmol) of (+/−)-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl were added in succession. The reaction mixture was then stirred at 110° C. for 2.0 h. After cooling, saturated aqueous ammonium chloride solution and ethyl acetate were added and the reaction mixture was filtered off with suction through kieselguhr. After phase separation, the organic phase was washed with sat ammonium chloride solution and sat. sodium chloride solution, dried over magnesium sulphate and concentrated under reduced pressure. The crude product was purified by chromatography on silica gel (mobile phase cyclohexane/ethyl acetate 80:1). This gave 4.44 g of the title compound in still slightly contaminated form (about 83% of theory).

Provenance & Evidence