Troxipide synthesis

Yield:30751-05-4 83.3%

Reaction Conditions:

with 5%-palladium/activated carbon;hydrogen in methanol;water at 80; under 15001.5 Torr; for 5 h;Solvent;Temperature;Pressure;

Steps:

7-11 Example 7

20 g of 3,4,5-trimethoxy-N-3-pyridylbenzamide prepared in the above step,50 g of methanol and 50 g of water were added to the reaction flask, stirred and dissolved, and then transferred to a hydrogenation vessel.Add 4 g of 5% palladium carbon, seal the can, and replace the tank three times with nitrogen.Then replace it three times with hydrogen, start stirring, heat up, when the temperature rises to about 80 °C,Hydrogenation pressure to 2.0Mpa, maintaining temperature of 80 °C, when the hydrogen pressure drops, make up the pressure,No hydrogen is absorbed after about 5 hours of reaction.The reaction was cooled to room temperature, the pressure in the tank was evacuated and replaced with nitrogen three times, and the hydrogenated solution was withdrawn.Palladium carbon is recovered by filtration, and the filtrate is transferred to a reaction flask, and the mixture is stirred and cooled to 0 to 5 ° C.Solid precipitation, filtration,Dry thoroughly to obtain a white solid, troxipide, 16.9 g.The yield was 82.6%, mp 174.2 to 176.5 ° C.15 g of crude product, 52.5 g of methanol and 52.5 g of ethyl acetate were added to the reaction flask.Stir at a temperature of stirring, and then add 1.0 g of activated carbon and stir for 30 minutes.The activated carbon is filtered off and the filtrate is transferred to another reaction bottle.Cool down to about 20 ° C, and continue to crystallization after 2 hours of filtration at this temperature.After sufficiently drying, 12.5 g of a white solid troxipide was obtained in a yield of 83.3%.Mp 178.1 ~ 179.3 ° C, purity 99.91%.

References:

CN109354581,2019,A Location in patent:Paragraph 0066-0085