An alternative approach would be to utilize novel conversion schemes using robust base metals that are stable in the presence of biogenic impurities.2 We show that electrosynthesis represents a promising approach for the direct processing of unpurified broths.2,3 The water, salts, and acidic impurities already present in the medium provide a suitable electrolyte, while protons in the solution provide the hydrogen required for the desired transformation. Muconic acid was converted to 3HDA with a 94% yield and 100% faradaic efficiency using lead (Pb) electrodes.4 Under these conditions, 3HDA can be produced at a competitive price of $2.00 kg-1. The reaction mechanism and the origin of the high selectivity to 3HDA will be discussed.
1. B.H. Shanks and P. Keeling, Bioprivileged Molecules: Creating Value from Biomass, Green Chem. 2017, advance article. https://dx.doi.org/10.1039/C7GC00296C
2. M. Suastegui, J. E. Matthiesen, J. M. Carraher, N. Hernandez, N. Rodriguez Quiroz, A. Okerlund, E. W. Cochran, Z. Shao, J.-P. Tessonnier, Combining Metabolic Engineering and Electrocatalysis: Application to the Production of Polyamides from Sugar, Angew. Chem. Int. Ed., 2016, 55, 2368-2373. http://dx.doi.org/10.1002/anie.201509653
3. J. E. Matthiesen, J. M. Carraher, M. Vasiliu, D. A. Dixon, J.-P. Tessonnier, Electrochemical Conversion of Muconic Acid to Biobased Diacid Monomers, ACS Sustainable Chem. Eng., 2016, 4, 3575-3585. http://dx.doi.org/10.1021/acssuschemeng.6b00679
4. J. E. Matthiesen, M. Suástegui, Y. Wu, M. Viswanathan, Y. Qu, M. Cao, N. Rodriguez-Quiroz, A. Okerlund, G. Kraus, D. R. Raman, Z. Shao, J.-P. Tessonnier, Electrochemical Conversion of Biologically Produced Muconic Acid: Key Considerations for Scale-up and Corresponding Technoeconomic Analysis, ACS Sustainable Chem. Eng., 2016, 12, 7098-7109. http://dx.doi.org/10.1021/acssuschemeng.6b01981