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 asymmetricsynthesis 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
Application of a Recyclable Pseudoephedrine Resin in Asymmetric Alkylations on Solid Phase
作者:Panee C. Hutchison、Tom D. Heightman、David J. Procter
DOI:10.1021/jo0354950
日期:2004.2.1
A pseudoephedrine resin has been successfully employed in asymmetric alkylations on solid phase. Immobilized pseudoephedrine amides are conveniently prepared by the one-step attachment of pseudoephedrine to Merrifield resin through the hydroxyl group and subsequent acylation on nitrogen. Deprotonation and alkylation of the resin-bound amides proceeds smoothly. Ketones and alcohols are cleaved from