A 1,5-diaza-2,4-(λ4P+, λ6P−)-diphosphorinane

The oxidation of the 1,3-diaza-4,6-diphosphorine 1 with tetrachloroorthobenzoquinone 2 led, unexpectedly, to the formation of 1,5-dimethyl-2,2-bis(dimethyl-amino)-4,4,4,4-bis-(tetrachloro-o-phenylenedioxa)-1,5-diaza-2,4-λ⁴, λ⁶-diphosphorinane-6-one 4 , containing two phosphorus atoms of opposite formal charge and different coordination number. The X-ray crystal structure analysis of 4 revealed the presence of a six-membered ring with an unusual conformation.