摘要 |
Sterically hindered phosphoramidates such as N,N'-bis[di-(2,6-xylenoxy)phosphinyl]piperazine are prepared by the reaction of a sterically hindered diaryl chlorophosphate, such as di-(2,6-xylyl) chlorophosphate, with a basic nitrogen compound containing at least two basic N-H groups, preferably a heterocyclic compound such as piperazine, in the presence of calcium oxide as an acid acceptor. The reaction is conducted in the presence of at least one dipolar aprotic solvent.
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