Solid acid catalyzed aldol dimerization of levulinic acid for the preparation of C10 renewable fuel and chemical feedstocks
作者:Ananda S. Amarasekara、Bernard Wiredu、Tony L. Grady、Rocio Garcia Obregon、Davor Margetić
DOI:10.1016/j.catcom.2019.02.022
日期:2019.5
diastereomeric pairs of 3-(2-methyl-5-oxo-tetrahydrofuran-2-yl)-4-oxopentanoic acid and 3-acetyl-2-methyl-tetrahydro-5-oxo-2-furanpropanoic acid by spectroscopic and computational methods. A mechanism is proposed to explain the formation of five dimerization products where the major product is formed via the aldol condensation of C5 enol form of levulinic acid and four minor products are arising from the aldol condensations
使用一系列固体酸催化剂研究了乙酰丙酸的酸催化缩合反应:Amberlyst-15,SiO 2 -SO 3 H,Dowex50WX8,Carbon-SO 3 H,TiO 2 -SO 3 H,Al 2 O 3 -SO 3 H,H 3 PW 12 O 40和Nb 2 O 5 .H 2O在110–130°C的纯净条件下。鉴定出主要的二聚产物为四氢-2-甲基-5,γ-二氧代-2-呋喃戊酸。另外,鉴定出四个次要产物为3-(2-甲基-5-氧代-四氢呋喃-2-基)-4-氧戊酸和3-乙酰基-2-甲基-四氢-5-氧代-2的非对映异构对。 -呋喃丙酸的光谱学和计算方法。提出了一种机制来解释五种二聚产物的形成,其中主要产物是通过乙酰丙酸的C5烯醇形式的醛醇缩合形成的,而四个次要产物是由乙酰丙酸的C3烯醇形式的醛醇缩合产生的。使用SiO 2 -SO 3可获得最高的总收率56%作为固体酸催化剂的H和质量平衡的提醒是未反应的乙酰丙酸。SiO