Leitner Andreas, Shu Chutian, Hartwig John F
Department of Chemistry, Yale University, P.O. Box 208107, New Haven, CT 06520-8107, USA.
Proc Natl Acad Sci U S A. 2004 Apr 20;101(16):5830-3. doi: 10.1073/pnas.0307967101. Epub 2004 Apr 5.
Individual diastereomeric phosphoramidites and mixtures of diastereomeric phosphoramidites were evaluated in the iridium-catalyzed amination of allylic carbonates. The original process was conducted with a phosphoramidite ligand containing a resolved 2,2-dihydroxy-1,1-binaphthyl (BINOL) group and a diastereomerically and enantiomerically pure bis(phenethyl)amino group. Evaluation of the structure of the active catalyst and relative rates for reactions in the presence of catalysts containing diastereomeric ligands led to the identification of a phosphoramidite that provided the amination product with enantiomeric excess similar to the original, more structurally and stereochemically complex ligand and that contains a racemic BINOLate and an N-benzylphenethylamino group on phosphorus.
在铱催化的烯丙基碳酸酯胺化反应中,对各个非对映异构亚磷酰胺及非对映异构亚磷酰胺混合物进行了评估。最初的反应过程使用了一种亚磷酰胺配体,该配体含有拆分的2,2 - 二羟基 - 1,1 - 联萘基(联萘酚,BINOL)基团以及非对映异构和对映异构纯的双(苯乙基)氨基。对活性催化剂的结构以及在含有非对映异构配体的催化剂存在下反应的相对速率进行评估后,确定了一种亚磷酰胺,该亚磷酰胺提供的胺化产物的对映体过量与原始的、结构和立体化学更复杂的配体相似,并且在磷上含有外消旋联萘酚盐和N - 苄基苯乙氨基。