Cyclotrimethylenetriphosphinic Acid.

The cyclotrimethylenetriphosphinic acid (1), isoelectronic to the cyclotriphosphoric acid, is formed in the hydrolysis of 1,1,3,3,5,5-hexakis(dimethylamino)-1λ ,3λ ,5λ -[1,3,5]triphosphinine. Compound 1 is stable to acids and bases. On heating for a longer period of time in D O each of the three methylene groups is monodeuterated.