Sodium Hydroxide → 3-Hydroxytridec-12-enoic acid

Purification by distillation (Kugelrohr, 135° C./0.2 torr) gave ethyl 3-hydroxy-12-tridecenoate as a colorless oil (12.3 g, 80% yield). To this ester (10.8 g, 42.2 mmol) in dioxane (50 ml) at room temperature was added 1M NaOH (50 ml). After one hour, the resulting slurry was diluted with water and washed twice with hexane. The aqueous layer was acidified with 10% citric acid, and the resulting solid collected by filtration and dried in vacuo to give 3-hydroxy-12-tridecenoic acid as a white solid, mp 62°-64° C. (8.65 g, 90% yield). To a solution of this hydroxy-acid (8.60 g, 37.6 mmol) in DMF (27 ml) at room temperature were added t-butyl-dimethylsilyl chloride (10.8 g) and imidazole (9.7 g). The reaction was stirred for 24 hours, poured into ice water (250 ml), and extracted three times with hexane. The extracts were combined, dried (Na ), filtered, and evaporated to give the bis-silyl derivative as a light yellow oil (14.5 g, 84% yield).