Eidgenössische Technische Hochschule Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland.
J Am Chem Soc. 2015 Apr 29;137(16):5296-9. doi: 10.1021/jacs.5b01951. Epub 2015 Apr 17.
The use of formaldehyde N,N-dialkylhydrazones as neutral C1-nucleophiles in the iridium-catalyzed substitution of allylic carbonates is described for two processes. Kinetic resolution or, alternatively, stereospecific substitution affords configurationally stable α,α-disubstituted aldehyde hydrazones in high enantiomeric excess and yield. This umpolung approach allows for the construction of optically active allylic nitriles and dithiolanes as well as branched α-aryl aldehydes. A catalyst-controlled reaction with Enders' chiral hydrazone derivatives followed by diastereoselective nucleophilic addition to the hydrazone products constitutes a two-step stereodivergent synthesis of chiral amines.
描述了使用甲醛 N,N-二烷基腙作为中性 C1-亲核试剂，在铱催化的烯丙基碳酸酯取代反应中的两种方法。动力学拆分或立体特异性取代以高对映过量和收率得到构型稳定的α,α-二取代醛腙。这种反转方法可用于构建光学活性的烯丙基腈和二硫杂环戊烷以及支链α-芳基醛。催化剂控制的反应与 Enders 手性腙衍生物反应，然后对腙产物进行非对映选择性亲核加成，构成了手性胺的两步立体发散合成。
