By Raesa Zia, Adrian Coello, Arshpreet Brar
Faculty mentor: Dr. Davis Oldham
The purpose of this lab was to separate the individual enantiomers of the alcohol 2-ethyl,1-hexanol, to analyze the toxicity of the product, 2-ethyl-1-hexyl acetate. A reaction was carried out combining Amano PS lipase and 2-ethyl-1-hexanol, with a percent yield 74%. From completing GC-MS of the crude product, it was visible that the product was a mixture of 2-ethyl-1-hexyl acetate and 2-ethyl-1-hexanol.
From the total product, the percentage of S enantiomer for the ester was 84% for S enantiomer. The alcohol had 45% for the S enantiomer and 54% for the R enantiomer. After running the product through column chromatography, the yield was 61% so there was a percent recovery of 8.2 %. H1NMR of the pure product was taken, and peaks were distinguished at 2.05 and 1.29 ppm for the ester while peaks at 3.99, 3.55, and 0.88 ppm were present for the initial alcohol. The alcohol peaks were determined through NMR to be at the peaks located at higher ppm due to the alcohol containing greater electronegativity than the ester. In addition, the number of hydrogens for the alcohol peak at 1.29 ppm was 17 which is close to the expected 16 Hs of the actual structure of the initial alcohol. Because the number of hydrogens indicates there was a single enantiomer, it can be concluded that the product was comprised of slow or S-enantiomer, while the fast R-enantiomer was used up in reaction.
