NEW SYMMETRIC DIISOPROPYLPHOSPHORYL-S-ALKANEDI YLDIISOTHIOUREAS. INVESTIGATIONS ON THEIR SYNTHESIS

Symmetric dialkylphosphoryl-S-alkanediyldiisothiouas (RO)2P(O)NHC(=NH)S(CH2)n SC(=NH)NHP(O)(OR)2 (I, R = isopropyl; n = 2–5) have potential coordination sites involving O, P, N and S as donors atoms. For their synthesis, common two-phase reactions between the corresponding diisothiourea derivatives and diisopropyi phosphonate were unsuccessful. Herein we describe a new synthesis for such compounds using diisopropyl chlorophosphonate. Two new bis-phosphorylated alkanediyldiisothioureas with increasing carbon chain (I; n = 3, n = 5) were prepared by this method.