75413-96-6Relevant academic research and scientific papers
Non-electronic aromatic ring activation by simple steric repulsion between substituents in 1-methylquinolinium salt systems
Iwai, Kento,Yokoyama, Soichi,Asahara, Haruyasu,Nishiwaki, Nagatoshi
, p. 50 - 57 (2020/01/21)
A systematic study of non-electronic activation of an aromatic ring was performed using a series of 8-substituted 1-methylquinolinium salts. As the 8-substituent became bulkier, the quinoline framework was distorted by steric repulsion between substituents at the 1- A nd 8-positions. This was accompanied by lack of coplanarity, which brought about dearomatization. Consequently, quinolinium ions possessing a bulky 8-substituent exhibited high reactivity undergoing nucleophilic addition at the 2-position efficiently. We demonstrate that the activation was achieved sterically and not electronically.
Selectivity in the Hydrogenation of 6- and 8-Substituted-quinolines
Hoenel, Michael,Vierhapper, Friedrich W.
, p. 1933 - 1939 (2007/10/02)
Quinoline (1) and the 6- or 8-substituted-quinolines (2)-(14) (R = Me, Pri, But, Ph, OMe, OH, CF3, or F) were hydrogenated catalytically on platinum under either weakly basic (solvent MeOH) or strongly acidic (solvent CF3CO2H) conditions.In methanol the only product was the corresponding 1,2,3,4-tetrahydro-compound.In trifluoroacetic acid, compounds hydrogenated in the benzene ring were isolated as major products; both electron-withdrawing and electron-donating substituents at C-6 or C-8 cause (sometimes drastic) reduction in yield.The products were characterized by their 1H and 13C n.m.r. spectra.
