Hydrochloric Acid → (2-Methylcyclohexyl)methanamine

Participants

Reaction Steps

In a 3-liter GL autoclave fitted with a electromagnetic stirrer are added 226.5 g of N-benzylisoindoline, 545 g of 7.2% hydrochloric acid aqueous solution (pH 4.0) and 26 g of 5% palladium-carbon catalyst (50% water-containing). The reaction mixture is subjected to a hydrogen-pressure of 20 kg/cm2 and a temperature of 130° C. After a 10 hour hydrogen introduction, the drop in the rate of the hydrogen-absorption is observed, at this point the introduction of hydrogen is ceased to terminate the reaction. After the termination of reaction, the catalyst is filtered out from the reacted solution. By the result of the capillary chromatographic analysis, the yield of cis-hexahydroisoindoline is 83.8%. In addition, 0.1% of trans-hexahydroisoindoline and 0.7% of 2-methylcyclohexylmethylamine is formed. After cooling the reacted solution, 240 g of 20% sodium hydroxide aqueous solution is added to neutralize, and it is extracted with toluene. After concentrating the organic phase, the residue is purified by distillation to give 99.7 g of cis-hexahydroisoindoline (yield 79.6%).

Provenance & Evidence