AN ANSWER TO THE SPIRO VERSUS ANSA DILEMMA IN CYCLOPHOSPHAZENES .16. SYNTHESIS AND CRYSTAL-STRUCTURE OF THE 1ST SPIRO SPECIES FROM DITHIADIAMINES

Aminolysis of hexachlorocyclotriphosphazene, N3P3Cl6, by dithiadiamines in suitable conditions yields mono-SPIRO species which constitute new macrocyclic monocyclophosphazenic structures containing sulphur atoms in their loops. Such (S,S) compounds are isologous to previously described oxygenated cyclophosphazenic cages which are commonly capable of inclusion of "hard" metals. Thus, one may expect that (S,S) cages will be useful for inclusion of "soft" metals. The X-ray structure of the (S,S) mono-SPIRO derivative from 3,7-dithianonane-1,9-diamine (coded as SS 232) reveals two crystallographically independent molecules in the unit cell, and also shows the conformations of SPIRO loops.