Ammonium Chloride → 4-[9-Chloro-1-(2,4-dichlorophenyl)-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazol-6-yl]hexan-2-one

Temperature

0 °C

To a solution of 3-[9-chloro-1-(2,4-dichlorophenyl)-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazol-6-yl]-N-methoxy-N-methylpentanamide (148.6 mg, 0.30 mmol) in tetrahydrofuran (10 mL) was added methylmagnesium bromide (3.0 M in diethyl ether, 0.3 mL, 0.9 mmol) at 0° C. The reaction mixture was stirred at 0° C. for 2 hr and at room temperature for 1 hr. Methylmagnesium bromide (3.0 M in diethyl ether, 0.3 mL, 0.9 mmol) was added to the reaction mixture at room temperature. After the mixture was stirred at room temperature for 2 hr, aqueous ammonium chloride was added to the reaction mixture. The mixture was extracted with ethyl acetate. The organic layer was washed with brine, dried over anhydrous magnesium sulfate, and concentrated in vacuo. The residue was purified by flash chromatography on silica gel eluting with a 20-60% ethyl acetate/n-hexane gradient mixture to give the title compound (96.0 mg, 0.213 mmol, 71%) as colorless crystals.

1. stirringAfter the mixture was stirred at room temperature for 2 hr
2. extractionThe mixture was extracted with ethyl acetate
3. washThe organic layer was washed with brine
4. dry with materialdried over anhydrous magnesium sulfate
5. concentrationconcentrated in vacuo
6. customThe residue was purified by flash chromatography on silica gel eluting with a 20-60% ethyl acetate/n-hexane gradient mixture

ORD record

ord-868cffe73ff54caa9833e19add9dfb6e

Source dataset

uspto-grants-2014_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08901141B2