83049-36-9Relevant academic research and scientific papers
Sterically crowded heterocycles. XII. Atropisomerism of (1-aryl-3,5-diphenyl-1H-pyrrol-2-YL)(phenyl)methanones
Klvana, Robert,Pohl, Radek,Pawlas, Jan,Cejka, Jan,Dvorakova, Hana,Hrabal, Richard,Boehm, Stanislav,Kratochvil, Bohumil,Kuthan, Josef
, p. 651 - 666 (2007/10/03)
Some 1-(2-substituted phenyl)-and 1-(1-naphthyl)-2,4,6-triphenylpyridinium perchlorates were treated with potassium hexacyano ferrate(III)-potassium hydroxide reagent to give the title pyrroles. Restricted rotation around the C-N bond in the products is demonstrated by NMR experiments with homochiral shift reagents, by semiempirical PM3 calculations as well as using their atropodiastereoselective and enantioselective transformations. Racemisation barriers for the (R)-2-(N-methyl-N-phenylcarbamoyl) derivative were estimated from NMR and polarimetric measurements.
OXIDATION OF POLYSUBSTITUTED PYRIDINIUM SALTS
Nesvadba, Petr,Kuthan, Josef
, p. 1494 - 1502 (2007/10/02)
Oxidation of 1-substituted 2,4,6-triphenylpyridinium salts Ia-Ij with potassium ferricyanide in an alkaline medium was accompanied by contraction of the pyridine ring and formation of 1,2,3,5-tetrasubstituted pyrroles II.The derivative IIf underwent facil
