| One of organictin compounds, dibutyltin dimethoxide(DBDMOS), is the most effective catalyst for preparing alkyl ester. In this paper, the reaction system and perpatation conditions of DBDMOS from dibutyltin oxide(DBOS) were mainly studied. The products were applied in some catalytic reactions to study the catalytic properties, which methoxyl group was introduced. A process with DBOS and methanol(MeOH) as raw materials for making DBDMOS was determined, and the decomposition and catalysis of alkyl carbamate(MC) were compared. Operating conditions which influence the preparation condition of DBDMOS were measured as following: Reaction temperature 180.0℃, reaction time 5h, the material quantity tatio was MeOH:MC:DBOS=3:3:1. Under the conditions, the yield of DBDMOS exceeds 86%.The primary products was purification via methanol and n-hexane extraction. The products and raw materials have been characterized by means of IR, 1H-NMR and ICP-MS. The results indicate that dibutyltin dimethoxide has been prepared. To examine the activity of DBDMOS, the product was used as catalyst for the dimethyl carbonate(DMC) synthesis reaction and the transesterification reaction of fatty acid methyl ester. In the process of DMC synthesis reaction, the catalytic property of DBDMOS is better than that of DBOS as catalyst. The amount of catalyst obviously reduced, reaction time reduced by half, while the yield of DMC increased. But the reaction temperatures of two reactions are similar. With DBDMOS as catalyst, tetrahydrofuran as the solvent and low temperature, hydrocarbon and DMC were prepared from fatty acid methyl ester and MeOH and the yield of DMC exceeds 0.47%. This reaction system was studied for the first time to provide a new method which to mineralize of biodiesel and synthesis of DMC. The results have important value in the technics of the preparation of dialkyl carbonate, as well as the organic reactions of introduction the -OCH3 group via nucleophilic substitution.
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