A structural examination of the impact of oxygenated side chains in Ephedra compounds in the catalytic asymmetric addition of diethylzinc to aldehydes |
| |
Authors: | Melissa A Dean Shawn R Hitchcock |
| |
Institution: | Department of Chemistry, Illinois State University, Normal, IL 61790-4160, USA |
| |
Abstract: | An investigation of the impact of oxygenated side chains in Ephedra compounds on the catalytic asymmetric addition of diethylzinc to aldehydes has been conducted. (1R,2S)-Ephedrine and (1S,2S)-pseudoephedrine were alkylated with either alkyl halides or β-alkoxyalkyl halides to afford a series of ligands 9a–h and 10a–h. These compounds were employed in the enantioselective addition of diethylzinc to a variety of aldehydes. It was determined that the presence of oxygen could have a negative effect in terms of obtaining high levels of enantiomeric discrimination, but the effect is diminished with higher levels of substitution near the oxygen. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|