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- The Juliá–Colonna epoxidation is an asymmetric poly-leucine catalyzed nucleophilic epoxidation of electron deficient olefins in a triphasic system. The reaction was reported by Sebastian Juliá at the Chemical Institute of Sarriá in 1980, with further elaboration by both Juliá and Stefano Colonna (Istituto di Chimica Industriale dell'Università, Milan, Italy). In the original triphasic protocol, the chalcone substrate is soluble in the organic phase, generally toluene or carbon tetrachloride. The alkaline hydrogen peroxide oxidant is soluble primarily in the aqueous phase, and the reaction occurs at the insoluble polymer layer at the interface of the two phases. Alternative biphasic and monophasic protocols have been developed with increased substrate accessibility and reaction rate. The efficient enantioselective catalytic epoxidation under mild conditions is of great synthetic utility. Not only are epoxides effective synthons for a range of transformations, they have a significant presence in natural products structures. Furthermore, the reaction has been effectively scaled up to industrially useful levels, with work conducted notably by Bayer and Evonik. Finally, the enzyme-like activity of the poly-amino acid segments is suggestive of a role of the reaction in the prebiotic origin of life. (en)
- 朱莉娅-科隆纳环氧化反应（Juliá–Colonna epoxidation）是一个以聚亮氨酸为催化剂的碳-碳双键不对称环氧化反应。该反应在1980年由塞巴斯蒂安·朱莉婭（Sebastian Juliá）报道，以及由朱莉婭和斯蒂法諾·科隆納（Stefano Colonna）同时做的进一步阐述。 原始的反应模式为三相反应，包含了水相、有机相和催化剂相。作为反应物的查耳酮衍生物溶于有机溶剂（例如甲苯或四氯化碳）中，成为有机相。碱性过氧化氢溶液为水相。反应则发生在既不溶于水相，也不溶于有机相的催化剂聚亮氨酸的表面。甚至的改进方法也已开发出来，改进后的反应活性和速率均有显著提高。 该反应是在温和条件下，立体选择性地环氧化双键的有效手段，因而在有机合成上具有重大的价值:环氧化物不仅是许多有机合成的中间体，许多天然产物也都是过氧化物。此外，经 拜耳 （页面存档备份，存于互联网档案馆）（Bayer）和埃佛歷克 （页面存档备份，存于互联网档案馆）（Evonik）等人的工作，该反应已经能够有效地应用于工业生产。最后，该反应的催化剂聚氨基酸具有类似酶的性质，因而该反应也有助于对的研究。 (zh)
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- Ternary Complex Formation in the Juliá–Colonna Epoxidation (en)
- Poly-leucine α-Helix Active Site Structure in the Juliá–Colonna Epoxidation (en)
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- Figure 4: Hydrogen bonding with the N-terminal residues stabilizes the peroxide enolate intermediate and orients the structure for ring closing with hydroxide displacement. The chalcone peroxide enolate is shown in green with hydrogen bonding interactions in red. The amino acid side-chains are omitted for clarity. Numbering refers to the amino group of each amino acid in the 7-mer, beginning at the N-terminus. Image inspired by Kelly et al. (en)
- Figure 3: The Juliá–Colonna Epoxidation proceeds by random steady-state formation of a ternary complex prior to reaction to form the peroxide enolate intermediate and final epoxide product. Image adapted from Carrea et al. (en)
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- Julia-Colonna Active Site Structure1.png (en)
- Julia-Colonna Epoxidation Ternary Complex3.png (en)
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- 朱莉娅-科隆纳环氧化反应（Juliá–Colonna epoxidation）是一个以聚亮氨酸为催化剂的碳-碳双键不对称环氧化反应。该反应在1980年由塞巴斯蒂安·朱莉婭（Sebastian Juliá）报道，以及由朱莉婭和斯蒂法諾·科隆納（Stefano Colonna）同时做的进一步阐述。 原始的反应模式为三相反应，包含了水相、有机相和催化剂相。作为反应物的查耳酮衍生物溶于有机溶剂（例如甲苯或四氯化碳）中，成为有机相。碱性过氧化氢溶液为水相。反应则发生在既不溶于水相，也不溶于有机相的催化剂聚亮氨酸的表面。甚至的改进方法也已开发出来，改进后的反应活性和速率均有显著提高。 该反应是在温和条件下，立体选择性地环氧化双键的有效手段，因而在有机合成上具有重大的价值:环氧化物不仅是许多有机合成的中间体，许多天然产物也都是过氧化物。此外，经 拜耳 （页面存档备份，存于互联网档案馆）（Bayer）和埃佛歷克 （页面存档备份，存于互联网档案馆）（Evonik）等人的工作，该反应已经能够有效地应用于工业生产。最后，该反应的催化剂聚氨基酸具有类似酶的性质，因而该反应也有助于对的研究。 (zh)
- The Juliá–Colonna epoxidation is an asymmetric poly-leucine catalyzed nucleophilic epoxidation of electron deficient olefins in a triphasic system. The reaction was reported by Sebastian Juliá at the Chemical Institute of Sarriá in 1980, with further elaboration by both Juliá and Stefano Colonna (Istituto di Chimica Industriale dell'Università, Milan, Italy). (en)
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- Juliá–Colonna epoxidation (en)
- 朱莉娅-科隆纳环氧化反应 (zh)
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