A SATURATED INORGANIC 6-MEMBERED RING CON TAINING PHOSPHORUS(V), HYDRAZINE AND SULFUR(IV) WITH A TWIST-BOAT CONFORMATION

Diethyl aza-4lambda5-phosphacyclohexane-2,6-dicarboxylate, C14H21N4O6P S2, was synthesized as a second example of an inorganic heterocycle co ntaining sulfur(IV), phosphorus(V) and two substituted hydrazine units . The molecular structure is very similar to that of the corresponding P=O compound. It is the E isomer. The ring adopts a conformation betw een the boat and twist forms with large P-N-N-S torsion angles [75.4 ( 4) and 66.2 (6)-degrees]. The mean N-N bond distance of 1.381 (7) angs trom is at the lower end of the expected range and there are, as in th e P=O compound, two different S-N distances in the ring [1.713 (5) and 1.758 (6) angstrom].