دانلود رایگان مقاله انتقال هیدروژن از نیتروآرنس به آریلامینس کاتالیز شده توسط کاتالیزور اکسیژن MoS2

Abstract

We present an efficient approach for chemoselective synthesis of various functionalized arylamines from nitroarenes over an oxygen-implanted MoS2 catalyst (O-MoS2). The HRTEM, XRD, XPS, Raman, EXAFS and NH3-TPD characterizations show the existence of MoIVOx structure and abundant coordinative unsaturated (CUS) Mo sites in the 2D-layer structure of O-MoS2. In the transfer hydrogenation of nitroarenes with hydrazine hydrate, the MoIVOx structure works as the catalytic active center. The N2H4 selectively decomposes to the active hydrogen species in polar electronic states (Hδ− and Hδ+), which show high chemoselectivity toward the nitro reduction over Cdouble bond; length as m-dashC, Cdouble bond; length as m-dashC, and Ctriple bond; length of mdashN groups. The O-MoS2 catalyst can be recovered in a facile manner from the reaction mixture and recycled four times without any significant loss of activity.

4. Conclusions

In summary, we present an efficient approach for chemoselective synthesis of various functionalized arylamines from corresponding nitroarenes by an oxygen-implanted MoS2 catalyst. The robust O-MoS2 catalyst can be easily separated and reused four times without any loss in its catalytic performance under the air condition, which is attributed to the cooperative effect between the active MoOx structure and its surrounding MoS2 skeleton. Furthermore, in this transfer hydrogenation reaction, the active hydrogen species in polar electronic states as H− and H+ are generated by N H bond activation of N2H4, which is beneficial for nitroarenes reduction.We believe that ourfindings will broaden the application of MoS2 and MoOx catalysts in the mild liquid-phase reactions.