The first photo-mediated process enabling the generation of halide radicals by halogen-atom transfer (XAT) is described. This novel reactivity pattern relies on the use of 1,2-dihaloethanes for the generation of unstable carbon radicals by XAT, which after β-scission, release halide radicals that have been used in selective hydrohalogenations of unsaturated hydrocarbons.
Photoredox-catalyzed hydrodifluoromethylation of alkenes has become an effective method to introduce difluoromethyl group into organic molecules. As the reported methods involve either photocatalysts or superstoichiometric amounts of additives, we herein describe a simple alternative without using photocatalyst or additive for the hydrodifluoromethylation of alkenes, through photoactivation of dif
hydroxylamine derivatives and heterocycles is presented. A range of heterocycles, including quinoxaline-2(1H)-ones, azauracils, chromones, and quinolones, are capable for this process, allowing the direct synthesis of valuable heteroarylethylamine derivatives. Structurally diverse reaction substrates, including drug-based scaffolds, were successfully applied, demonstrating the practicality of this method.
提出了光氧化还原催化的未活化烯烃与O -酰基羟胺衍生物和杂环的 1,2-氨基杂芳基化反应。一系列杂环化合物,包括喹喔啉-2(1 H )-酮、氮尿嘧啶、色酮和喹诺酮,都能够进行该过程,从而可以直接合成有价值的杂芳基乙胺衍生物。成功应用了结构多样的反应底物,包括基于药物的支架,证明了该方法的实用性。
Method for preparing alpha-(4-isobutylphenyl) propionic acid or its precursor
申请人:NIPPON PETROCHEMICALS CO., LTD.
公开号:EP0347939A1
公开(公告)日:1989-12-27
A method for preparing α-(4-isobutylphenyl)propionic acid or its precursor is here disclosed which comprises a step A of forming p-isobutylstyrene from p-isobutylethylbenzene and a step B of forming α-(4-isobutylphenyl)propionaldehyde from p-isobutylstyrene or a step C of forming α-(4-isobutylphenyl)propionic acid or its alkyl ester from p-isobutylstyrene.
Furthermore, a method for preparing said p-isobutylethylbenzene is also disclosed which comprises alkylating isobutylbenzene or 4-ethyltoluene with ethylene or propylene.