2-hydro-2-oxo-l,3,2-dioxaphosphorinane

An interesting example of the coordination polymerisation of a phosphacyclic monomer is represented by the polymerisation of oxyphosphonoyloxytrimethy-lene (2-hydro-2-oxo-l,3,2-dioxaphosphorinane) in the presence of triisobutyla-luminium as the catalyst [181,182], This polymerisation, carried out at a temperature of 25 °C, produced, in relatively high yield, poly(oxyphosphonoy-loxytrimethylene) which appeared to be a high molecular weight polymer (Table 9.2). 

The transesterification of H-phosphonate diesters with 1,3 propanediol is accompanied however by the formation of 2-hydro-2-oxo-l,3,2-dioxaphosphorinane in 75 to 85% yield [28], This compound results from the nucleophilic attack of the terminal hydroxyl group of the monotransesterificated product at the phosphoras atom. 

Polymerization of the 2-hydro-2-oxo-l,3,2-dioxaphosphorinane, initiated anionically or with aluminum alkyls, resulted in poly(alkylene H-phosphonate)s [291],... 

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