Pseudoephedrine as a Practical Chiral Auxiliary for the Synthesis of Highly Enantiomerically Enriched Carboxylic Acids, Alcohols, Aldehydes, and Ketones
作者:Andrew G. Myers、Bryant H. Yang、Hou Chen、Lydia McKinstry、David J. Kopecky、James L. Gleason
DOI:10.1021/ja970402f
日期:1997.7.1
pseudoephedrine as a practical chiral auxiliary for asymmetric synthesis is described in full. Both enantiomers of pseudoephedrine are inexpensive commodity chemicals and can be N-acylated in high yields to form tertiary amides. In the presence of lithium chloride, the enolates of the corresponding pseudoephedrine amides undergo highly diastereoselective alkylations with a wide range of alkyl halides to
伪麻黄碱作为不对称合成的实用手性助剂的使用进行了全面的描述。伪麻黄碱的两种对映异构体都是廉价的商品化学品,可以高产率进行 N-酰化以形成叔酰胺。在氯化锂的存在下,相应的伪麻黄碱酰胺的烯醇化物与多种卤代烷发生高度非对映选择性的烷基化反应,以高产率得到 α-取代产物。然后,这些产品可以在一次操作中转化为高度对映异构的羧酸、醇、醛和酮。