New Chiral Ligands Derived from Mandelic Acid: Synthesis and Application in the Asymmetric Phenyl Transfer Reaction to an Aromatic Aldehyde
作者:Carsten Bolm、Lorenzo Zani、Jens Rudolph、Ingo Schiffers
DOI:10.1055/s-2004-829184
日期:——
Starting from inexpensive enantiopure (R)- and (S)-mandelic acid, a range of u-hydroxy-2-oxazolines has been prepared. The synthesis involves the condensation of the acid chloride with a vicinal amino alcohol, followed byintramolecular cyclization to form the oxazoline ring. The resulting compounds have been used as ligands in the asymmetric phenyl transfer reaction to 4-chlorobenzaldehyde, employing
从廉价的对映体纯 (R)- 和 (S)-扁桃酸开始,已经制备了一系列 u-羟基-2-恶唑啉。该合成涉及酰氯与连位氨基醇的缩合,然后进行分子内环化以形成恶唑啉环。所得化合物已用作配体,用于不对称苯基转移反应至 4-氯苯甲醛,使用三苯基硼烷和二乙基锌的混合物作为苯基源。已经实现了良好的产率(高达 76%)和适中的对映选择性(高达 35%)。