NOVEL 6-MEMBERED AND 8-MEMBERED HETEROCYCLES - A TRITHIADIAZAPHOSPHORINANE AND A PENTATHIADIAZAPHOSPHOCINE

We report the single-crystal X-ray structure determinations of two nov el phosphorus-, nitrogen- and sulfur-containing heterocycles, namely, 4,6-bis[2-(2-methyl)- xo-5-phenyl-1,2,3,4,6,5-trithiadiazaphosphorinan e, C14H23N2OPS3, and -phenyl-1,2,3,4,5,6,8,7-pentathiadiazaphosphocine , C14H23N2OPS5. The phosphorinane compound is unusual in that it displ ays a high degree of steric compression in the S-S-S bond angle, which has a value of only 96.3 degrees. The phosphocine compound has bond a ngles similar to those found in S-8 rings. One S-S-S-S torsion angle, however, is compressed to 30 degrees. The phosphocine has two conforma tionally identical molecules in the asymmetric unit.