Keto boronate reduction : 1,7-asymmetric induction
Keto boronate reduction : 1,7-asymmetric induction
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酮硼酸酯还原：1,7-不对称诱导
DOI：
10.1021/ja00069a067
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发表时间：
1993
影响因子：
15
通讯作者：
Kevin L. Bobbitt
中科院分区：
文献类型：
--
作者：
G. Molander;Kevin L. Bobbitt
除2 e外，纯化的二醇的产率接近（参见等式1）。所有新的化合物已充分表征光谱（NMR，13 C NMR，IR），元素组成已建立燃烧分析和/或高分辨率质谱。除非另有说明，通过粗Mosher二酯的19 F NMR测定。在所有情况下，还测量了外消旋Mosher二酯的19 F NMR光谱以确保19 F NMR光谱中的足够分辨率。c通过多重500 MHz NMR测定！对应于与伯酯相邻的亚甲基质子（4.15- 4.36ppm）。d通过四氢呋喃衍生物的Mosher酯的毛细管GC分析测定。对溶剂效应的解释是，酮硼酸酯的无环、未活化形式（其在还原过程中几乎不提供非对映体偏差）对更紧密结合的、反应性更低的还原剂如BHrSMe 2的还原更不敏感。12
Refers to yields of purified diol, except for 2e (see eq 1). All new compounds have been fully characterized spectroscopically (NMR, 13C NMR, IR), and elemental composition has been established by combustion analysis and/or high-resolution mass spectrometry. 1 23456 De-termined by 19F NMR of the crude Mosher diester unless otherwise specified. In all cases, the 19F NMR spectra of the racemic Mosher diesters have also been measured to ensure adequate resolution in the 19F NMR spectra. c Determined by 500-MHz NMR of the multiple! corresponding to the methylene protons adjacent to the primary ester (4.15—4.36 ppm). d Determined by capillary GC analysis of the Mosher ester of the tetrahydrofuran derivative. explanation for the solvent effect is that the acyclic, unactivated form of the keto boronate (which would provide little diastereofacial bias in the reduction process) is less susceptible to reduction by more tightly bound, less reactive reducing agents like BHrSMe2. 12