PURPOSE: To obtain a 1,4-dialkyl-2,3-piperazinedione which is useful as a solvent and the like by reaction of a specific amine with an oxalate diester at a temp, lower than a specific temp, to achieve the improvement of the reaction yield and selectivity, simplified isolation of purified product and recovery and recycle of the reaction solvent.
CONSTITUTION: The reaction of an N,N'-dialkylethylenediamine of formula I with an oxalic diester of formula II (R' is an alkyl) such as di-n-butyl oxalate is carried out at a temp lower than 130°C (for example, at 25-130°C) to give the objective compound of formula III. It is preferred that the reaction is effected in the presence of no solvent or in an alcohol same as that formed as a by-product during the reaction and after the target product is isolated, the recovered solvent is reused.
MIZUTA HIDEKI
NARUSE HIROSHI
NAGATA TERUYUKI
