METHANOL-BASED SYNTHETIC REACTIONS OVER SOLID-BASE CATALYSTS

Novel methods for catalytically synthesizing alpha,beta-unsaturated compounds and higher alcohols were developed, where methanol was used as a key reagent for C-C bond formation. Reactants were saturated ketones, esters, nitriles, or alcohols besides methanol, and CH2 = or CH3- group is introduced into their methyl or methylene carbons by the addition of methanol. For the catalytic synthesis of alpha,beta-unsaturated compounds, magnesium oxide activated by manganese ion or chromium ion has been found to give the most effective catalytic performance, The most promising application of this synthetic method is demonstrated by the selective synthesis of acrylonitrile from acetonitrile and methanol over Mn-MgO catalyst. The selectivity to acrylonitrile was more than 95% and no deactivation of the catalyst was observed. The method was also applied to the conversion of acetone to methyl vinyl ketone and methyl propionate to methyl methacrylate. Condensations of various primary alcohols (C-2-C-5) with methanol were carried out at atmospheric pressure over various metal oxides having a solid-base property. The reactions gave one or two carbon higher alcohol than the reacted primary alcohol. MgO catalyst was most active for the reaction and yielded the alcohol products in high selectivty (>80%). Based on the kinetic measurements, reaction mechanisms for both reactions are discussed.