Pyridones, 1 -alkyl—continued

Grabowska et al. (2008) prepared a composite oxide ZnAl O by microwave-assisted hydrothermal treatment of a precursor mixture of lydroxides obtained by precipitation of aluminum and zinc nitrates. Various studies show that ZnAl O is nanosized and is a micro/mesoporous material with large a suifaee area (140 mVg). The gas phase catalytic methylation of 4-hydroxypyridine in the presence of the ZnAljO catalyst was performed in a continuous process at atmospherie pressure in the temperature range of 240-360 °C. A mixture of O- and N-alkylated products, namely 4-methoxypyridine and N-methyl-4-pyridone were obtained. The alkylation of 4-hydroxypyridine with methanol at 345 °C offered 87.6% selectivity towards N-methyl-4-pyiidone with about 89% 4-methoxypyridine conversioa... 

---