Trichloroacetyl chloride → HCID 10003659, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 303 mg (0.556 mmol) of 5-amino-1-(1-benzoylethyl-3-butyl-4-[(2'-cyanbiphenyl-4-yl)-methyl]-4H-1,2,4-triazolium bromide (from Step E) and 6 g of polyphosphoric acid was stirred at 80° C. under N2 for 5 hours. The cooled mixture was treated with an excess of ice. After the ice had melted, the water was decanted off, and the residue was partitioned between EtOAc and saturated aqueous NaHCO3. The organic phase was dried over Na2SO4, filtered, and concentrated in vacuo. The residual oil was dissolved in a minimum volume of CH2Cl2 and treated with 200 μl (145 mg, 1.43 mmol) of triethylamine. The resulting solution was cooled to 0° C. and stirred under N2 as 137 μl (223 mg, 1.23 mmol) of trichloroacetyl chloride was added. The solution was allowed to warm to room temperature. After 1 hour at room temperature, the solution was concentrated in vacuo. The residue was leached with 25 ml of ether. The filtered ether solution was washed with 25 ml of 0.2N HCl and then with 25 ml of 0.2N NaOH. The ethereal phase was dried (Na2SO4), filtered, and evaporated. Column chromatography of the residue on silica gel (elution with 99:1 and then 98:2 CH2Cl2 -MeOH) afforded 95.0 mg (39%) of the title compound as a brown solid of indefinite mp, suitable for use in the next step; homogeneous by TLC in 19:1 CH2Cl2 -MeOH.

Provenance & Evidence