Group 13 Lewis Acid Adducts of [PCl₂N]₃

Abstract

Phosphazene polymers are classically synthesized by the high-temperature, ring-opening polymerization (ROP) of [PCl(2)N](3) to give [PCl(2)N](n), followed by functionalization of [PCl(2)N](n) with different side groups. We investigated the interactions of [PCl(2)N](3) with Lewis acids because Lewis acids have been used to induce the high-temperature ROP of [PCl(2)N](3). The reactions of [PCl(2)N](3) with MX(3) (M = group 13, X = halides), under strict anaerobic conditions gave adducts [PCl(2)N](3)·MX(3). Adducts were characterized by X-ray crystallography and multinuclear and variable-temperature NMR studies, and mechanistic understanding of their fluxional behavior in solution was achieved. The properties of the [PCl(2)N](3)·MX(3) adducts at or near room temperature strongly suggests that such adducts are not involved directly as intermediates in the high-temperature ROP of [PCl(2)N](3).

RETRACTED ARTICLE: Synthesis and characterization of trimeric phosphazene based ionic liquids with tetrafluoroborate anions and their thermal investigations

“…[PCl 2 N] 3 ·MX 3 obtained by excluding water or HX is the main product. Whenever MX 3 (AlCl 3 , GaCl 3 , AlBr 3 ) was used, water traces were always found, and by isolating [PCl 2 N] 3 ·HMX 4 (HMX 4 : HAlCl 4 , HGaCl 4 , HAlBr 4 ) structures as the second product, they detected the location of the protonation by X-ray crystallography 11 , 12 . In recent years, PILs have been synthesized using a variety of cyclophosphazene compounds and bulky acids (salicylic, gentisic, γ-resorcylic acids), and the biological activity of these PMOSs has been investigated 13 – 15 .…”

Group 13 Superacid Adducts of [PCl2N]3

“…BCl 3 (1 M solution in heptane) from Aldrich was used as received. [PCl 2 N] 3 ·MX 3 were prepared following the published procedures . HCl gas (Praxair, 99%) was purified by fractional vacuum distillation through two −78 °C (dry ice/acetone bath) traps and stored in a glass bulb attached to the high-vacuum line, which was equipped with a manometer.…”

“…In our studies of the reactions of group 13 Lewis acids MX 3 (MX 3 = AlCl 3 , GaCl 3 , AlBr 3 ) with [PCl 2 N] 3 , we have observed two major types of products. With the most rigorous exclusion of water or HX, the adducts [PCl 2 N] 3 ·MX 3 are the major products. Herein we continue this work and describe the effect of added water or HX to [PCl 2 N] 3 /MX 3 systems.…”

Phosphazene-Based Ionic Liquids

“…The protonated specie distorted the P 3 N 3 ring and weakened the two P − N bonds that flank the protonated nitrogen. The crystal structures of Figure 4 [21,22].…”