Rj. Lu et al., SYNTHESIS OF 3-(1-ARYLAMINOCARBONYL-5-AMINO)-1,2,4-TRIAZOLYL BENZYL SULFIDE, SULFOXIDE AND SULFONE, Phosphorus, sulfur and silicon and the related elements, 108(1-4), 1996, pp. 221-230
3-(1-arylaminocarbonyl-5-amino)-1,2,4-triazolyl benzyl sulfides were s
ynthesized by the reaction of 5-amino-3-benzylthio-1,2,4-triazole and
its analogue with the aryl isocyanate. It was found that there was gre
at influence by the property and position of substituents X, Y on the
chemical shift of H-N-2 in the H-1 NMR spectra. By means of molecular
mechanics calculations, the substituent effect on the chemical shift o
f H-N-2 was rationalized. The chemocontrolled oxidation of 3-(1-arylam
inocarbonyl-5-amino)-1,2,4-triazolyl benzyl sulfide to sulfoxide and s
ulfone respectively was performed after a careful study of the influen
ce of the concentration of H2O2 and the reaction temperature on the ox
idation reaction. In H-1 NMR spectra of sulfoxides(II), the protons of
a methylene group near the SO chiral center coupled to appear as a qu
artet in the AB pattern. The SO, SO2 decreased the electronic density
around H-N-2, 5-NH2, and thus moved the proton absorption to a lower h
eld. The experimental showed that the ratio of sulfoxide(II)/sulfone(I
II) was influenced by the electronic property of substituents X, Y on
the aryl moiety.