(S)-3-Methyl-5-(2-pyrrolidinyl)-1,2,4-oxadiazole synthesis

Yield:343246-61-7 90%

Reaction Conditions:

with trifluoroacetic acid in dichloromethane at 20; for 2.5 h;

Steps:

1 Synthesis of Compound QY-1-95

QY-7-40 (100 mg, 0.39 mmol) was dissolved in 3 ml of dichloromethane, and the solution was transferred to 8 ml pressure flask. 0.3 ml of trifluoroacetic acid was added dropwise to the reaction solution at room temperature, and the solution was mixed and stirred well. The reaction was monitored in real time by LC-MS which was completed in 2.5 hours. The reaction solution was transferred to 100 ml round-bottomed flask, 20 ml of dichloromethane was added, and the solvent was removed by a rotary evaporator; the reaction mixture was separated and purified by C18 reversed-phase chromatography column (water: acetonitrile=0-80%) to obtain 54 mg of pale yellow oily liquid with a yield of 90%. MS (ESI) m/z 154 (M+H)+.

References:

US2022/213077,2022,A1 Location in patent:Paragraph 0093; 0101-0102