| 摘要 |
A process is taught for recovering a white reaction product of a cyanuric halide with an amine reactant (white being indicative of the product's high purity), in high yield. In the absence of a solvent for either reactant, the first step comprises reacting the cyanuric halide, as a finely divided solid, with a liquid amine which is to provide a saturated heterocyclic amine group, such as a polysubstituted piperazinone, piperazine, or piperidine as the substituent for each of the three halogen atoms of the cyanuric halide used. This solventless process carried out under essentially anhydrous conditions, with a large molar excess of the amine reactant chosen, not only shortens the long time required to make the desired tri-substitution in a conventional solvent process, but also obviates using a pressurized reactor. Since (i) the reaction temperature is relatively low, (ii) there is no solvent, and (iii) the amine reactants are relatively high-boiling, and the reaction occurs in the liquid phase, there is no build-up of pressure. Fortuitously, the appropriate amount of alkanol and concentrated aqueous alkali provides a partition coefficient such that salt formed by neutralization of the excess amine hydrohalide is effectively precipitated nearly quantitatively. In addition to providing "easy" processing conditions, the solventless reaction in our process provides higher yields than can be obtained, under comparable conditions, with the 'solvent process'; a lower by-product 'make' because of the low temperature and substantially atmospheric pressure used; and, the batch reaction is completed in less than 12 hr.
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