Author:

Keywords:

Science & Technology, Physical Sciences, Technology, Chemistry, Multidisciplinary, Green & Sustainable Science & Technology, Engineering, Chemical, Chemistry, Science & Technology - Other Topics, Engineering, Anilines, Biorenewable chemicals, Benzylic oxidation, Beckmann rearrangement, Green Metrics, Bioaromatics, BOND FORMATION, DEPOLYMERIZATION, CATALYSTS, CARBON, CONVERSION, HYDROGENOLYSIS, FRACTIONATION, FRAGMENTATION, ISOCYANIDES, DERIVATIVES, PYROLYSIS, 0301 Analytical Chemistry, 0502 Environmental Science and Management, 0904 Chemical Engineering, 3401 Analytical chemistry, 4004 Chemical engineering

Abstract:

A new approach to synthesize valuable 3,4- dialkoxyanilines and alkyl propionates from lignin-derived 4- propylguaiacol and -catechol with overall isolated yields up to 65% has been described. The strategy is based on the introduction of nitrogen via a Beckmann rearrangement. Amino introduction therefore coincides with a C-defunctionalization reaction; overall a replacement of the propyl chain by an amino group is obtained. The process only requires cheap bulk chemicals as reagents/reactants and does not involve column chromatography to purify the reaction products. Furthermore, all carbon atoms from the biorenewable lignin-derived monomers are transformed into valuable compounds. Greenness was assessed by performing a Green Metrics analysis on two dialkoxyanilines. A comparison was made with literature routes for these compounds starting from a petrochemical substrate.