ISOLATION, SYNTHESIS AND REACTIVITY OF A KEY MACROBISLACTONE - 1,4,7-TRIOXACYCLOTRIDECANE-8-13-DIONE

Macrobislactone 1, 1,4,7-trioxa-cyclotridecane-8-13-dione, believed to be the cause of the fogging of car windscreens by an oily film, has been formally synthesised from diethylene glycol and adipic acid and its content in commercial polyester formulations has been estimated. Study of its ring-opening potential towards both anionic and enzymatic reagents reveal surprizing stability in polyester formulations, coupled with anomalous high susceptibility in the pure state to the lipase Candida antarctica, immobilized as Novozyme(TM). Assay of macrobislactone 1 in a range of polyesters suggest that there is significantly more of this kev lactone present than trends would predict. Reasons for this behaviour are advanced following modelling studies and from thermodynamic considerations.