Oxazolium Salts as Organocatalysts for the Umpolung of Aldehydes
作者:Venkata Krishna Rao Garapati、Michel Gravel
DOI:10.1021/acs.orglett.8b02636
日期:2018.10.19
and redox esterification reactions. An N-mesityl oxazolium salt catalyzed homobenzoin reaction of aromatic, heteroaromatic, and aliphatic aldehydes delivered α-hydroxy ketones in high yields. This newtype of catalyst proved remarkably effective for the Stetter reaction of challenging substrates such as β-alkyl-α,β-unsaturated ketones and electron-rich aromaticaldehydes in comparison to common thiazolium
Intermolecular Photoredox Coupling: Alternative to Norrish Type II Reaction and Yang Cyclization in Ketones with γ‐C−H Bonds
作者:Heiko Hoffmann、Michael W. Tausch
DOI:10.1002/ejoc.202100434
日期:2021.7.15
A new reaction pathway of the photoconversion of butyrophenone is reported. In addition to the NorrishtypeII fragmentation and Yang cyclization, intermolecular species are generated: 1,2-Dibenzoylethane, 2-phenacylacetonitrile and pinacols. They account for approx. 20 % of the converted starting material, similar to the Yang product. The acetophenone enol intermediate has been identified as an H-atom
报道了丁酰苯光转化的新反应途径。除了 Norrish II 型断裂和 Yang 环化之外,还会产生分子间物质:1,2-二苯甲酰乙烷、2-苯甲酰乙腈和频哪醇。他们约占。20% 的转化原料,类似于杨产品。苯乙酮烯醇中间体已被确定为拟议机械步骤的 H 原子供体。