Amino acids are organic compounds that can be found all around us in the world in the building blocks of proteins and peptides. One class of compounds which can be synthesized from amino acids are amino alcohols, another critical compound in society. Amino alcohols are key components in agricultural products and pharmaceutical products. Therefore, developing an efficient and cost-effective method for performing this transformation is an important area of research. The currently used industrial process is to reduce petroleum-derived amino acids with NaBH4. However, this process is time-consuming and costly because of the need for an intermediate stage esters and further processing afterwards to produce the amino alcohols.
A proposed alternative to NaBH4 is hydrogenation using ruthenium supported on carbon catalyst in the presence of phosphoric acid. The advantage of this reaction over the currently used industrial process is that Ru-catalyzed hydrogenation has been shown to have high selectivity to amino alcohols and can maintain the optical purity, a critical component in the use of amino alcohols in pharmaceuticals. Unfortunately, this process is not currently cost-effective or reproducible on an industrial scale because of the expense of the catalyst and the fact that the acid co-catalyst cannot be recycled, adding to the cost. Our proposed solution was to impregnate the catalyst with a polymer that can created acidic active sites within the catalyst pores, eliminating the need for the acid. By impregnating 2.9 wt% polyacrylate onto a Ru supported by alumina catalyst, we were successful in converting 51.8% of our alanine to alaninol without the addition of any acid co-catalyst. The catalyst can then be filtered out and reused, adding a major economic and environmental advantage for hydrogenation versus the current industrial process.
Karno, Rachel, "Catalytic Hydrogenation of Amino Acids using Polymer-Derived Microenvironments" (2017). Honors College. 309.