Study On Tertiary Amine Catalytically Oxidized By Titanium-silica Hollow Spheres

N-oxides of tertiary amine are a class of important organic intermediates. They are widely used in commodity, abstergent, textile auxiliary, synthetic fiber, pharmaceutical industry, coloring matter, catalysis etc. So the study of the amine oxide is of great significance.For the N-oxides of tertiary amine, the traditional catalysts used are some homogeneous catalyst such as acetic acid. Now, the heterogeneous catalysts are more widely used, such as heteropolyacid catalyst, exchange resin, Ti-Si molecular sieve etc.In this paper, the synthesis of tertiary amine oxides were studied using titanium?silica hollow spheres as catalyst. The main content is as follows: (a) Preparation of titanium?silica hollow spheres. Normaly, taking TEOS as silicon source, tetrabutyl titanate as titanium source, nitric acid as catalyst,Span-80 as surfactant, kerosene oil as oil phase in micro-emulsion system; thus the titanium?silica hollow spheres were obtianed. (b) In the presence of titanium?silica hollow spheres as catalyst, the N-methylmorpholine-N- oxidie (NMMO) was synthesized from N-methylmorpholine. (c) the pyridine N-oxide and 2-methylpyridine N-oxide were synthesized from pyridine and 2-methylpyridine. The catalysts were characterized by polarized light microscopy, scanning electron microscopy, X-ray diffraction and FT-IR. The effects of the reagent ratio, reaction temperature and reaction time on the yield of tertiary amine N-oxides were investigated in detail. The products were characterized and confirmed by FT-IR, 1HNMR. The yields of NMMO, pyridine N-oxide, 2-methylpyridine N-oxide are 89.2%, 90.3%, 34.4%, respectively.Titanium?silica hollow spheres in the presence of H2O2 have many benefits, for example, reusability, easy separation and no disposal, which is a good enviroment and useful green catalyst for oxidation of tertiary amine.