3885-29-8Relevant articles and documents
Metal-catalyzed reductive deamination of glutamic acid to bio-based dimethyl glutarate and methylamines
De Schouwer, Free,Cuypers, Thomas,Claes, Laurens,De Vos, Dirk E.
supporting information, p. 1866 - 1876 (2017/06/09)
Glutamic acid is a promising renewable platform molecule which is abundantly available in biomass waste streams; it is also efficiently manufactured by fermentation. Here we report the reductive deamination of glutamic acid to bio-based dimethyl glutarate and methylamines. In order to recycle nitrogen in an industrially relevant co-product, glutamic acid was modified to N,N-dimethylglutamic acid by a mild reductive alkylation with Pd/C. Subsequently, selective C-N hydrogenolysis in methanol resulted in dimethyl glutarate and trimethylamine. A wide screening of transition metals (Pt, Pd, Rh and Ru) immobilized on various supports showed that the highest yields of dimethyl glutarate were obtained with Pt/TiO2. An FTIR study and kinetic experiments on metal-loaded and unloaded supports demonstrate that the interplay between the metal and the moderate acidity of the support results in the excellent C-N hydrogenolysis activity and selectivity. Finally, reaction parameter optimization resulted in 81% yield of dimethyl glutarate with 1 wt% Pt/TiO2 at 225 °C, 30 bar H2 after 8 h.