三乙烯二胺催化Michael加成对(E)-β-芳(烷)氧基丙烯酸酯的立体选择性合成

Stereoselective Synthesis of( E)-β-aryloxyl( alkyloxyl) Acrylates By DABCO-catalyzed Michael Addition

以异丙醇为溶剂(或无溶剂),采用三乙烯二胺(DABCO)催化的取代苯酚(或取代苄醇)与2-丁炔酸乙酯的Michael加成反应合成了14个(E)-β-芳氧基丙烯酸酯化合物(3a^3n,3f^3n为新化合物)和3个烷氧基丙烯酸酯化合物(5a,5b和5k,5b和5k为新化合物),收率分别为85%~99%和60%~68%,其结构经1H NMR,13C NMR和HR-MS(ESI)表征。以3a的合成为例,优化了合成3的反应条件。结果表明:在最优反应条件(DABCO为催化剂,异丙醇为溶剂,于25℃反应9 h)下,3a收率92%,E∶Z>99∶1。

Fourteen （E）-β-aryloxyl acrylates（3a^3n） and three （E）-β-alkyloxyl acrylates（5a, 5b, 5k） were synthesized by DABCO-catalyzed Michael addition of substituted phenols（ or substited benzyl alcohols） with ethyl 2-butynoate in i-PrOH（or solvent-free conditions）.Among them, 3f^3n, 5b and 5k were novel compounds.The yields of 3 and 5 were 85%~99%and 60%~68%, respectively.The structures were characterized by 1 H NMR, 13 C NMR and HR-MS（ESI）.The reaction conditions for syn-thesizing 3 were optimized based on synthesizing 3a.The results showed that the optimum conditions for synthesizing 3a were as follows：DABCO as catalyst, i-PrOH as solvent, reaction at 25℃for 9 h.The yield and E∶Z of 3a were 92%and above 99∶1.