51680-04-7Relevant articles and documents
Synthetic method of quinolinone compounds
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Page/Page column 4-13, (2019/10/01)
The invention discloses a synthetic method of quinolinone compounds. The synthetic method is characterized by comprising the following steps: taking aniline and oxalyl chloride as raw materials, carrying out stirring in an organic solvent, sequentially ad
Stereoselective control in the Staudinger reactions involving monosubstituted ketenes with electron acceptor substituents: Experimental investigation and theoretical rationalization
Qi, Hengzhen,Li, Xinyao,Xu, Jiaxi
supporting information; experimental part, p. 2702 - 2714 (2011/05/19)
The stereoselectivity of the Staudinger reactions involving monosubstituted ketenes with electron acceptor substituents was investigated experimentally by determination of the product stereochemistry and theoretically via DFT calculations. The results indicate that imines preferentially attack the less sterically hindered exo-side of the ketenes to generate zwitterionic intermediates. Subsequently, for cyclic imines, the intermediates undergo a conrotatory ring closure directly to produce β-lactams, while for linear imines, the imine moiety of the intermediates isomerizes to more stable intermediates, which further undergo a conrotatory ring closure to afford trans-β-lactams. The steric hindrance and the isomerization, rather than the torquoelectronic effect, play crucial roles in controlling the stereoselectivity in the practical Staudinger reactions involving monosubstituted ketenes with electron acceptor substituents, although the unaccessible borylketene with a powerful electron acceptor group controls the stereoselectivity torquoelectronically, in theory.
