Selective Ammoximation of Ketones via In Situ H<sub>2</sub>O<sub>2</sub> Synthesis
Richard J. Lewis, Kenji Ueura, Xi Liu, Yukimasa Fukuta, Tian Qin, Thomas E. Davies, David Morgan, Alex Stenner, James Singleton, Jennifer K. Edwards, Simon J. Freakley, Christopher J. Kiely, Liwei Chen, Yasushi Yamämoto, Graham J. Hutchings
Abstract
High Resolution Image Download MS PowerPoint Slide The ammoximation of ketones to the corresponding oxime via the in situ production of H 2 O 2 offers a viable alternative to the current means of industrial-scale production, in particular for the synthesis of cyclohexanone oxime, a key precursor to Nylon-6. Herein, we demonstrate that using a bifunctional catalyst, consisting of Pd-based bimetallic nanoparticles immobilized onto a TS-1 carrier, it is possible to bridge the considerable condition gap that exists between the two key distinct reaction pathways that constitute an in-situ approach (i.e., the direct synthesis of H 2 O 2 and ketone ammoximation). The formation of PdAu nanoalloys is found to be crucial in achieving high reactivity and in promoting catalytic stability, with the optimal formulation significantly outperforming both alternative Pd-based materials and the monometallic Pd analogue.