Regioselective Carbohydrate Oxidations: A Nuclear Magnetic Resonance (NMR) Study on Selectivity, Rate, and Side-Product Formation
作者:Niek N. H. M. Eisink、Martin D. Witte、Adriaan J. Minnaard
DOI:10.1021/acscatal.6b03459
日期:2017.2.3
to palladium/neocuproine catalyzed oxidation and subsequently analyzed by qNMR. Surprisingly, all studied glucosides, mannosides, galactosides, and xylosides show selective oxidation of the C3-OH. However, subsequent reaction of the resulting ketone moiety is the main culprit for side product formation. Measures are reported to suppress these side reactions. The observed differences in reaction rate
钯/新癸氨酸催化的糖苷氧化显示出对C3-OH的极佳选择性,但在甘露糖苷和半乳糖苷中,最初观察到非选择性氧化。为了进一步应用在更复杂的(低聚)糖中,就选择性和反应性而言,需要对反应有一个更好的了解。因此,合成了一组不同的糖苷,进行了钯/新星氨酸催化的氧化,随后通过qNMR进行了分析。出人意料的是,所有研究的糖苷,甘露糖苷,半乳糖苷和木糖苷均显示出对C3-OH的选择性氧化。然而,所得酮部分的后续反应是副产物形成的主要元凶。据报道,有措施抑制这些副反应。观察到的反应速率差异,葡萄糖苷氧化最快,