Abstract
Heating 3-methyl-1,2-butadienyl phosphonates with piperazine leads to the formation of 2-piperazinyl-butenyl phosphonates containing the enamine functionality. From the reaction of piperazine with four equivalents of 1,2-butadienyl phosphonate a bis(phosphonate) is obtained, in which the piperazine bridge links two phosphorylbutene fragments.
GRAPHICAL ABSTRACT
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