Diastereoselective reactions of ester enolates with epoxides
Diastereoselective reactions of ester enolates with epoxides
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酯烯醇化物与环氧化物的非对映选择性反应
DOI：
10.1021/jo00077a069
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发表时间：
1989
影响因子：
3.6
通讯作者：
Mark Whittaker
中科院分区：
文献类型：
--
作者：
S. K. Taylor;Jason A. Fried;Y. N. Grassl;A. Marolewski;E. A. Pelton;T. Poel;D. Rezanka;Mark Whittaker
Et），甲虫信息素，94%ee（通过手性GC）。产物的对映体纯度与其他报道的合成方法相比是有利的。20· 22当丙酸叔丁酯的烯醇化铝用（S）-环氧丙烷处理时，立体异构产物比率为83：16：1：< 1（2S，4S：2 R，4S：2S，4fi：2 R，4fi，假设转化反应）。非对映体产物可以通过柱色谱法分离，留下几乎光学纯的产物。这种化学方法在手性化合物合成中的应用显示出很高的前景，在（i）-红炔醇的首次合成中，这种烯醇化物化学方法的价值得到了进一步的证明。在这种情况下，关键步骤是将4-戊烯酸叔丁酯的烯醇化铝与1，2-环氧-11-十二碳炔结合。对映选择性。为了实现动力学对映选择，我们制备了（+）-和（-）-薄荷醇乙酸酯的铝烯醇化物，并用外消旋环氧丙烷（eq 3）处理它们。将反应
Et), the beetle pheromone, in 94% ee (by chiral GC). The enantiomeric purity of the product compares favorably with that of other reported syntheses. 20· 22 When the aluminum enolate of tert-butyl propionate was treated with (S)-propylene oxide, the stereoisomeric product ratio was 83: 16: 1:< 1 (2S, 4S: 2R, 4S: 2S, 4fi: 2R, 4fi, assuming an inversion reaction). The diastereomeric products can be separated by column chromatography, leaving an almost optically pure product. The use of this chemistry in thesynthesis of chiral compounds shows high promise.Further proof of the value of this enolate chemistry was demonstrated earlier in the use of it in the first syntehsis of (i)-rubrynolide. 23 In this case, a key step was the combination of the aluminum enolate of tert-butyl 4-pen-tenoate with 1, 2-epoxy-ll-dodecyne. Enantioselectivity. In attempts to achieve kinetic enantioselection, we prepared the aluminum enolates of (+)-and (-)-menthol acetate and treated them with racemic propylene oxide (eq3). The reactions were