Bhardwaj Siddhant, Patel Deep M, Forrester Michael J, Roling Luke T, Cochran Eric W
Department of Chemical and Biological Engineering, Iowa State University Ames IA 50011 USA
Center for Biorenewable Chemicals (CBiRC) Ames IA 50011 USA.
RSC Adv. 2024 Dec 13;14(53):39408-39417. doi: 10.1039/d4ra05226a. eCollection 2024 Dec 10.
Levulinic acid (LA) is a key platform molecule with current applications in the synthesis of several commodity chemicals, including amino-levulinic acid, succinic acid, and valerolactone. In contrast to existing petroleum-based synthesis pathway, biomass-derived --muconic acid (MA) offers a sustainable route to synthesize LA. Here, we show the complete decarboxylation of neat MA to LA without solvent at atmospheric pressure and mild temperature. In a series of sulfuric acid catalyzed experiments, we used a suite of one and two-dimensional NMR techniques along with gas chromatography-mass spectrometry (GCMS) analysis and density functional theory (DFT) calculations to elucidate the intermediates involved in LA synthesis. Experimental kinetic studies revealed rate constants for the consumption of MA and the formation of LA, with activation energies calculated to be 16.10 kJ mol and 158.18 kJ mol, respectively.
乙酰丙酸（LA）是一种关键的平台分子，目前应用于多种商品化学品的合成，包括氨基乙酰丙酸、琥珀酸和戊内酯。与现有的石油基合成途径不同，生物质衍生的粘康酸（MA）为合成LA提供了一条可持续的路线。在此，我们展示了在常压和温和温度下，纯MA无需溶剂即可完全脱羧生成LA。在一系列硫酸催化的实验中，我们使用了一套一维和二维核磁共振技术以及气相色谱-质谱联用（GCMS）分析和密度泛函理论（DFT）计算，以阐明LA合成过程中涉及的中间体。实验动力学研究揭示了MA消耗和LA形成的速率常数，计算得出的活化能分别为16.10 kJ/mol和158.18 kJ/mol。
