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The Tsuji–Trost reaction (also called the Trost allylic alkylation or allylic alkylation) is a palladium-catalysed substitution reaction involving a substrate that contains a leaving group in an allylic position. The palladium catalyst first coordinates with the allyl group and then undergoes oxidative addition, forming the π-allyl complex. This complex can then be attacked by a nucleophile, resulting in the substituted product.〔''Strategic Applications of Named Reactions in Organic Synthesis (Paperback)'' by Laszlo Kurti, Barbara Czako ISBN 0-12-429785-4〕 This work was first pioneered by Jiro Tsuji in 1965〔''Organic syntheses by means of noble metal compounds XVII. Reaction of π-allylpalladium chloride with nucleophiles'' Tetrahedron Letters, Volume 6, Issue 49, 1965, Pages 4387-4388 Jiro Tsuji, Hidetaka Takahashi, Masanobu Morikawa 〕 and, later, adapted by Barry Trost in 1973 with the introduction of phosphine ligands.〔Trost, B. M.; Fullerton, T. J. "New synthetic reactions. Allylic alkylation." ''J. Am. Chem. Soc.'' 1973, ''95'', 292–294. .〕 The scope of this reaction has been expanded to many different carbon, nitrogen, and oxygen-based nucleophiles, many different leaving groups, many different phosphorus, nitrogen, and sulfur-based ligands, and many different metals (although palladium is still preferred).〔Rios, Itzel Guerrero; Rosas-Hernandez, Alonso; Martin, Erika; "Recent Advances in the Application of Chiral Phosphine Ligands in Pd-Catalysed Asymmetric Allylic Alkylation." Molecules, 2011, 16 970-1010. doi: 10.3390/molecules16010970〕 The introduction of phosphine ligands led to improved reactivity and numerous asymmetric allylic alkylation strategies. Many of these strategies are driven by the advent of chiral ligands, which are often able to provide high enantioselectivity and high diastereoselectivity under mild conditions. This modification greatly expands the utility of this reaction for many different synthetic applications. The ability to form carbon-carbon, carbon-nitrogen, and carbon-oxygen bonds under these conditions, makes this reaction very appealing to the fields of both medicinal chemistry and natural product synthesis. ==History== In 1962, Smidt published work on the palladium-catalysed oxidation of alkenes to carbonyl groups. In this work, it was determined that the palladium catalyst activated the alkene for the nucleophilic attack of hydroxide.〔Smidt, J., Hafner, W., Jira, R., Sieber, R., Sedlmeier, J. and Sabel, A. (1962), ''Olefinoxydation mit Palladiumchlorid-Katalysatoren''. Angewandte Chemie, 74: 93–102. 〕 Gaining insight from this work, Tsuji hypothesized that a similar activation could take place to form carbon-carbon bonds. In 1965, Tsuji reported work that confirmed his hypothesis. By reacting an allylpalladium chloride dimer with the sodium salt of diethyl malonate, the group was able to form a mixture of monoalkylated and dialkylated product.〔''Organic syntheses by means of noble metal compounds XVII. Reaction of π-allylpalladium chloride with nucleophiles'' Tetrahedron Letters, Volume 6, Issue 49, 1965, Pages 4387-4388 Jiro Tsuji, Hidetaka Takahashi, Masanobu Morikawa 〕 The scope of the reaction was expanded only gradually until Trost discovered the next big breakthrough in 1973. While attempting to synthesize acyclic sesquiterpene homologs, Trost ran into problems with the initial procedure and was not able to alkylate his substrates. These problems were overcome with the addition of triphenylphosphine to the reaction mixture. These conditions were then tested out for other substrates and some led to "essentially instantaneous reaction at room temperature." Soon after, he developed a way to use these ligands for asymmetric synthesis.〔''Asymmetric Transition Metal-Catalyzed Allylic Alkylations'' Barry M. Trost David L. Van Vranken Chem. Rev., 1996, 96 (1), pp 395–422 〕Not surprisingly, this spurred on many other investigations of this reaction and has led to the important role that this reaction now holds in synthetic chemistry. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Tsuji–Trost reaction」の詳細全文を読む スポンサード リンク
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