The reactions of phenolysis of cyclophosphazenes, leading to the formation of monoaryl oxide derivatives with an excess of the substrate, were studied. The interest in this reaction is dictated by the practical value of the reaction products, which are easily formed under the conditions of transphase catalysis, and also by the fact that the studied regularities of phenolysis can extend to a significant spectrum of transphase nucleophilic substitution reactions. The general regularities of the transphase reaction of phosphazenes phenolysis were established by the example of the interaction of 4-nitrophenol with a phosphornitrile chloride trimer in a two-phase system. It was shown that the topology of the transphase chemical interaction is influenced by the same factors as the limiting stage, and therefore, by varying the ratio of lipophilicity and nucleophilicity of the transphase reagent, one can purposefully change the place of its interaction with the substrate. It was shown that the phenolysis of cyclotriphosphazenes occurs in the bulk of the organic phase or, alternatively, in the organic sublayer adjacent to the phase separation boundary. The presented data suggested that the transphase reaction can be described in terms of a single mechanism, in contrast to the generally accepted division into extraction and phase transfer. Thus, the topology of the transphase chemical interaction is influenced by the same factors as the limiting stage, and therefore, by varying the ratio of lipophilicity and nucleophilicity of transphase reagents, one can purposefully change the zone of their interaction with the substrate. In this case, the rate of the homogeneous response and the hydrophilicity of the ionic agent must be taken into account. The features of the transphase reaction described here can be extended to other catalysts, such as betaines, the analogs of which have been used in various reactions of a similar type.
Phase Transfer Catalysis. Dehmlow E.V., Dehmlow S.S. Weinheim: VCH Verlagsgesellschaft, 1993.
Phosphorus Nitrogen Compounds: Cyclic, Linear, and High Polymeric Systems., Allcock, H.R. New York: Academ. Press, 2012.
Landini D., Maia A., Podda G., Secci D., Yan Y. Mechanism and anion activation in solid–liquid phase-transfer reactions catalysed by cyclophosphazenic polypodands. Comparison with cyclic analogue crown ethers. J. Chem. Soc., Perkin Trans. II. 1992. 1721.
Afonkin A., Shumeiko A., Popov A. Change in the topology of the stage of chemical interaction as a tool for controlling stereoselectivity in phase-transfer catalysis. Izv. Academy of Sciences, ser. chemical. 1995. (11): 2102.
Afonkin A., Shumeiko A., Kostrikin M., Popov A. Modeling of conditions of phase transfer catalysis – an effective method for studying its mechanism Russian Chemistry Journal. 1999. XLIII (1): 105.
Tamami B., Ghasemi S. Nucleophilic substitution reactions using polyacrylamide-based phase transfer catalyst in organic and aqueous media. Journal of the Iranian Chem. Soc. 2008. 5: 26.
Nogueira I., Pliego J., Josefredo R. Phenol alkylation under phase transfer catalysis conditions: Insights on the mechanism and kinetics from computations. Molecular Catalysis. 2021. 506. Article 111566.
Xu D., Pan Z. Phase transfer catalysis of a new cationic gemini surfactant with ester groups for nucleophilic substitution reaction. Chinese Chemistry Letters. 2014. 25 (8): 1169.
Nogueira I., Pliego J., Josefredo R. Theoretical study of the mechanism and regioselectivity of the alkylation reaction of the phenoxide ion in polar protic and aprotic solvents. Computational and theoretical chemistry. 2018. 1138: 117.
Pliego J., Riveros J. New insights on reaction pathway selectivity promoted by crown ether phase-transfer catalysis: Model ab initio calculations. Journal of Molecular Catalysis. A – Chemical. 2012. 363: 489.
West C., O’Brien R., Salter E. Impact of sulfur heteroatoms on the activity of quarternary ammonium salts as phase transfer catalysts for nucleophilic displacement reactions. Journal of Molecular Catalysis. A – Chemical. 2015. 398: 282.