Synthesis, Separation of Enantiomers and Barriers to Racemization of Some Sterically Hindered N-Aryl-1,2,3,4-tetrahydro-3,3-dimethyl-2,4-quinolinediones and Their Thio Analogues

Article abstract of DOI:10.1007/BF00811864

The novel N-aryl-1,2,3,4-tetrahydro-3,3-dimethyl-2,4-quinolinediones 1, 4 and 8 were thiated with Lawesson reagent and P4S10 to yield the monothio derivatives 2 and 5 and the dithio compounds 3, 6 and 9.Their enantiomers were separated by liquid chromatography on triacetyl- or tribenzoylcellulose.Rotation barriers for 1-4 and 8 were determined by thermal racemization and discussed in terms of steric effects. - Keywords.N-Aryl-1,2,3,4-tetrahydro-3,3-dimethyl-2,4-quinolinediones; N-Aryl-1,2,3,4-tetrahydro-3,3-dimethyl-quinoline-2-one-4-thiones; N-Aryl-1,2,3,4-tetrahydro-3,3-dimethyl-2,4-quinoline-dithiones; Enantioselective chromatography.