Triethylamine, aluminum complex

While high polymers of /3-lactones can also be formed by cationic polymerization, most of the commercial production seems to be by the anionic route. Carboxylate salts such as sodium acetate or benzoate are commonly the initiators, but other nucleophiles, such as triethylamine, betaine, potassium f-butoxide, aluminum and zinc alkoxides, various metal oxides and tris(dimethylamino)benzylphosphonium chloride (the anion of which is the initiator), are of value. Addition of crown ethers to complex the counter cation increases the rate of reaction. When the reaction is carried out in inert but somewhat polar organic solvents, such as THF or ethyk acetate, or without solvent, chain propagation is very fast and proceeds without transfer reactions. 

Preparation. Allyl chloride is condensed with phosphorus trichloride in the presence of aluminum chloride to give a complex, which is decomposed by water to allylphosphoric dichloride (I).1 This product reacts with. vyw-dimethylethyl-enediamine (triethylamine) to give the reagent (2).2... 

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