Synthesis of Octyl Dihydrocaffeate and Its Transesterification with Tricaprylin Catalyzed by Candida antarctica Lipase

This work aimed at producing a phenolic ester from dihydrocaffeic acid (DHCA), besides carrying out transesterification reactions of this ester with tricaprylin. The esterification reaction was performed in two ratios (1:1 and 1:3 DHCA:octanol), and the transesterification was done in four ratios (1:1, 1:2, 1:5, and 1:10) between the produced ester and tricaprylin. In the last, a Central Composite Rotatable Design was employed, varying the amount of enzyme (1.6-18.4%), reaction time (9.9-35.1 h), and temperature (43.2-76.8 degrees C) on reagent consumption percentage. Novozym 435 was the catalyst in all reactions. The highest ester yield (50%) occurred in 8 days. In transesterification reactions, higher consumption of the produced ester was achieved at ratios 1:5 and 1:10, obtaining, respectively, 29.6% and 21.1% of octyl dihydrocaffeate residual, in 24 h. At higher temperatures and time above 26 h, there was less octyl dihydrocaffeate residual (18.7%). Three different phenolic compounds were identified.