SYNTHESIS AND ACID-BASE PROPERTIES OF PHOSPHORYLATED DIAZACYCLOALKANES AND THEIR CYCLIC ANALOGS

Novel cyclopendant organophosphorus complexing agents, viz. 1,5-bis(2- diphenylphosphorylmethyl(or ethyl))-1,5-diazacyclooctane (1, 2) and 1- methyl-4-(2-diphenylphosphorylethyl)piperazine (3), were synthesized o n the basis of 1,5-diazacyclooctane and piperazine. The protonation co nstants of the compounds synthesized and some of their analogs were de termined by potentiometric titration in 70 % aqueous ethanol and in ni tromethane. The nitrogen atoms of the ring are the protonation sites i n all of the systems studied. The regularities of the variation of pro tonation constants have been explained by the formation of intramolecu lar hydrogen bonds. The conformational possibilities of the formation of H-bonds in the cations of the ligands have been examined by molecul ar mechanics.