Thermodynamic, spectroscopic, and density functional theory studies of allyl aryl and prop-1-enyl aryl ethers. Part 1. Thermodynamic data of isomerization
[EN] SULFOXIMINE GLYCOSIDASE INHIBITORS<br/>[FR] INHIBITEURS DE LA SULFOXIMINE GLYCOSIDASE
申请人:ASCENEURON S A
公开号:WO2018153508A2
公开(公告)日:2018-08-30
Compounds of formula (I) wherein A, R, W, Q, n and m have the meaning according to the claims can be employed, inter alia, for the treatment of tauopathies and Alzheimer's disease.
Thermodynamic, spectroscopic, and density functional theory studies of allyl aryl and prop-1-enyl aryl ethers. Part 1. Thermodynamic data of isomerization
作者:Esko Taskinen
DOI:10.1039/b101837j
日期:——
A chemical equilibration study of the relative thermodynamic stabilities of seventy isomeric allyl aryl ethers (a) and (Z)-prop-1-enyl aryl ethers (b) in DMSO solution has been carried out. From the variation of the equilibrium constant with temperature the Gibbs energies, enthalpies, and entropies of isomerization at 298.15 K have been evaluated. Because of their low enthalpies, the (Z)-prop-1-enyl aryl ethers are strongly favored at equilibrium, the Gibbs energies of the a→b isomerization ranging from −12 to −23 kJ mol−1. The entropy contribution is negligible in most reactions, but occasionally small positive values less than +10 J K−1 mol−1 of the entropy of isomerization are found. The equilibration studies were also extended to involve two pairs of related isomeric ethers with a Me substituent on C(2) of the olefinic bond. The Me substituent was
found to increase the relative thermodynamic stability of the allylic ethers by ca. 3.4 kJ mol−1.
Nickel Hydride Catalyzed Cleavage of Allyl Ethers Induced by Isomerization
作者:Andreas Berkefeld、Ivana Fleischer、Prasad M. Kathe
DOI:10.1055/s-0040-1706683
日期:2021.10
This report discloses the deallylation of O- and N-allyl functional groups by using a combination of a Ni-H precatalyst and excess Brønsted acid. Key steps are the isomerization of the O- or N-allyl group through Ni-catalyzed double-bond migration followed by Brønsted acid induced O/N–C bond hydrolysis. A variety of functional groups are tolerated in this protocol, highlighting its synthetic value