Catalytic reactions of pyridines. VI. Heterogeneous vapor-phase ring alkylation of pyridines with alcohols over H+-, Li+-, and alkaline earth cation-exchanged zeolites.

Abstract

The heterogeneous vapor-phase alkylation of pyridine with methanol was examined over metal cation-exchanged X-and Y-type zeolites in an atmosphere of nitrogen. β-Methylation was observed over H+-or Li+-exchanged zeolites, whereas α-and γ-methylation (the former occurred in preference) were observed over alkaline earth cation-exchanged zeolites. For example, at 400°C, the yields of α-, β-, and γ-picolines over the HY catalyst were 2.6, 12.2, and 2.6%, whereas those over the BaY catalyst were 22.7, 3.8, and 7.6%, respectively. This catalytic ring alkylation over metal cation-exchanged zeolites was also examined by the use of pyridine with ethanol and picolines with either methanol or ethanol.