condensations of aromatic, hetero-aromatic and α;β-unsaturated aldehydes with less reactive acetylacetone or ethyl acetoacetate. The reactions were performed in organic solvent in the presence of water. The functionalized trisubstituted alkenes and α,β,γ,δ-unsaturated carbonyl compounds could be obtained in moderate to good yields with E/Z selectivities up to >99:1. This biocatalytic reaction provided an alternative
摘要 B
LAP(来自地衣芽孢杆菌的
碱性蛋白酶)被用作芳香族、杂芳香族和 α;β-不饱和醛与反应性较低的
乙酰丙酮或
乙酰乙酸乙酯的 Knoevenagel 缩合反应的
生物催化剂。反应在有机溶剂中在
水存在下进行。可以以中等至良好的收率获得官能化的三取代烯烃和 α,β,γ,δ-不饱和羰基化合物,E/Z 选择性高达 >99:1。这种
生物催化反应为 Knoevenagel 缩合提供了另一种途径,这也证明了现有酶的非自然活性的新案例。