1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD) is an effective organocatalyst for acyl transfer as well as the ring-opening polymerization of cyclic esters. Its high activity is attributed to its ability to simultaneously activate both esters and alcohols, as demonstrated in a model reaction. This unique mechanism makes TBD a remarkably simple example of a bifunctional catalyst. The simplicity of the reaction conditions, the ready commercial availability of the catalyst, and its high activity provide an accessible methodology to allow future studies of tailor-made polyesters.
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