Synthesis of (.+‐.)‐α‐Allokainic Acid via the Zinc Acetate Catalyzed Cyclization of γ‐Isocyano Silyl Enolates.
Synthesis of (.+‐.)‐α‐Allokainic Acid via the Zinc Acetate Catalyzed Cyclization of γ‐Isocyano Silyl Enolates.
复制标题
通过乙酸锌催化 γ-异氰基甲硅烷基烯醇化物的环化合成 (.+-.)-α-别卡因酸。
DOI：
10.1002/chin.199221298
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Y. Ito
中科院分区：
文献类型：
--
作者：
M. Murakami;Naoki Hasegawa;M. Hayashi;Y. Ito
neurological diseases. 1'3 Recently, we described a fluor-ide-catalyzed addition of-isocyano carboxylates to, ß-unsaturated ketones in the presence of 2V, 0-bis (trimethylsilyl) acetamide (BSA) that gives the 1, 4-adducts (as the corresponding silyl enolates) in high yield. 4 Now, we describe a versatile synthetic route to pyrrolidine-2-carboxylic acids via the zinc (II) acetate catalyzed cycliza-tion of the 1, 4-adducts 1, and, furthermore, its successful application in a total synthesis of racemic-allokainic acid. Cyclization via the intramolecular-addition of nucleophiles to isonitriles has been utilized to synthesize various nitrogen-containing heterocycles. Ū The synthesis of pyrrolidine-2-carboxylic acids described here involves the step-by-step regioselective addition of an-isocyano car-boxylate (which is formally equivalentto an azomethine ylide that bears a carboxyl group6) to the carbon-carbon double bond of an enone(eq 1).
