Comparative Study of the Phospha- and Arsa-Wittig Reaction Using1H,75As and17O NMR Spectroscopy
作者:Christian Raeck、Stefan Berger
DOI:10.1002/ejoc.200600432
日期:2006.11
The existence of oxaarsetanes during an arsa-Wittigreaction has been proved by 1 H and 17 O NMRspectroscopy. 75 As NMR spectra were obtained from the corresponding arsonium salts and arsane oxides. The dynamic 1 H NMR spectra of phospha- and arsaylides were compared.
已通过 1 H 和 17 O NMR 光谱证明了在 arsa-Wittig 反应过程中存在氧杂亚锡烷。75 As NMR 光谱是从相应的砷盐和砷烷氧化物中获得的。比较了磷和亚砷酸内酯的动态 1 H NMR 谱。
Ionic Liquids: Just Molten Salts After All?
作者:Hon Man Yau、Si Jia Chan、Stephen George、James Hook、Anna Croft、Jason Harper
DOI:10.3390/molecules14072521
日期:——
recent years to characterise ionicliquids in terms of parameters that are well described for molecular solvents, using these to explain reaction outcomes remains problematic. Herein we propose that many reaction outcomes in ionicliquids may be explained by considering the electrostatic interactions present in the solution; that is, by recognising that ionicliquids are salts. This is supported by evidence
Double ortho meta regiocontrolled functionalisation of tricarbonyl-(η6-1-tert-butoxycarbonyl-2,3-dimethylbenzene) chromium; 17O NMR study of saponification-elimination mechanism
The title compound 1 promotes the attachment of an electrophilic group preferentially to the 2-methyl group while the 3-methyl group reacts slightly. A condensation mechanism of 1 with aldehyde involving a lactonisation step is confirmed by a labelling experiment.