Chemistry of cyclodicarbaphosphatriazene: Synthesis and structural studies of pentaerythritoxy-bridged and lariat ether type spirocyclic derivatives

Reactions of dilithiated diols [HO(CH2CH2O)n+1H, n = 1, 2 and 3] with 3,5-bis(N,N-dimethylamino)-1,1-dichlorodicarbaphosphazene (1) in THF have been carried out to afford the first examples of lariat ether type cyclocarbaphosphazene derivatives (C4H8O3PN)(Me2NCN)2 (2), (C6H12O4PN)(Me2NCN)2 (3) and (C8H16O5PN)(Me2NCN)2 (4). Reaction of the tetrasodium salt of pentaerythritol with 1 and bis(morpholino)dichlorodicarbaphosphazene (1a) yielded the first examples of pentaerythritoxy-bridged cyclodicarbaphosphatriazenes [(Me2NCN)2PN(OCH2)2]2C (5) and [(OC4H8NCN)2PN(OCH2)2]2C (6). The spectral and structural properties of these compounds are determined and compared with spirocyclic 1,3-propanedioxy derivative of 1 (7) and analogous compounds of cyclophosphazenes. The crystal structures of the compounds 4, 5 and 7 are reported. In addition, complexation studies of compounds 3 and 4 with NaI, KI, AgI and CuII ions were carried out by conductance measurements. The studies indicate mostly 1:1 complex formation between the metal ions and lariat ether type cyclocarbaphosphazene derivatives.