Dimethylformamide → Ethyl 4-(((1R)-2-(5-(2-fluoro-3-methoxyphenyl)-3-(2-fluoro-6-(trifluoromethyl)benzyl)-4-methyl-2,6-dioxo-3,6-dihydro-1(2H)-pyrimidinyl)-1-phenylethyl)amino)butanoate

Participants

Reaction Conditions

Reaction Steps

To a reactor was charged a solution of 3-((R)-2-amino-2-phenyl-ethyl)-5-(2-fluoro-3-methoxy-phenyl)-1-(2-fluoro-6-trifluoromethyl-benzyl)-6-methyl-1H-pyrimidine-2,4-dione 1e in isopropyl acetate (19.0 kg in 59.6 L solution). Dimethylformamide (18 L) was charged and the mixture was distilled under vacuum to remove the isopropyl acetate. Ethyl-4-bromobutyrate (7.83 kg) was charged to the reactor followed by diisopropylethylamine (5.87 kg). The reactor contents were heated to 55° C. and stirred until completion of reaction. The reactor was cooled to 20° C. and isopropyl acetate (110 L) and water (96 L) were added. The mixture was agitated and the layers allowed to settle. The water layer was removed and the organic layer was washed with water (95 L). The organic layer was treated with a solution of 85% phosphoric acid/H2O (10.4 kg/152 L). The mixture was agitated, allowed to settle, and the layers were separated. The organic layer was treated with a solution of 85% phosphoric acid/H2O (2.7 kg/19 L). The mixture was agitated, allowed to settle, and the layers were separated. The aqueous phosphate layers were combined and washed with isopropyl acetate (21 L). After layer separation, dichloromethane (109 L) was added to the aqueous layer, followed by slow addition of a solution of potassium carbonate/water (23.2 kg/29 L) while mixing. The layers were separated and the organic layer was concentrated by vacuum distillation. The solution was passed through a silica gel plug pre-conditioned with CH2Cl2 and the plug eluted using EtOH/CH2Cl2 (5 L/469 L). Appropriate portions were combined and the solution was concentrated by vacuum distillation. Ethanol (80 L) was charged to provide a concentrated stock solution of 4-((R)-2-[5-(2-fluoro-3-methoxy-phenyl)-3-(2-fluoro-6-trifluoromethyl-benzyl)-4-methyl-2,6-dioxo-3,6-dihydro-2H-pyrimidin-1-yl]-1-phenyl-ethylamino)-butyric acid ethyl ester 4a (82.9 kg total, ˜17.3 kg of 4a, 75% yield) that was used in the next step. LCMS (ESI) m/z 660.2 (MH+)

Provenance & Evidence