Substituent effects on thermal rearrangement of 3-(substituted phenyl)-4-(p-tolyl)-1,2,4-oxadiazole-5(4H)-thiones

Agirbas H., Toker A.

JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, vol.14, no.1, pp.58-61, 2001 (SCI-Expanded, Scopus) identifier identifier

  • Publication Type: Article / Article
  • Volume: 14 Issue: 1
  • Publication Date: 2001
  • Journal Name: JOURNAL OF PHYSICAL ORGANIC CHEMISTRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.58-61
  • Kocaeli University Affiliated: No

Abstract

The kinetics of the rearrangement of 3-(substituted phenyl)-4-(p-tolyl) 1,2,4-oxadiazole-5(4H)-thiones in solution were determined in the temperature range 160-200 C-degrees. From the correlation of logk against sigma, it was found that for m-Me, p-Cl and p-CN, the compounds rearrange with the homolytic cleavage of the N-O bond, whereas for p-Me, H and m-NO2, the rearrangement occurs with the heterolytic cleavage of the N-O bond. In comparison with the uncatalysed rearrangement, Cu catalysis greatly increased the rate of the rearrangement of 3-(m-chlorophenyl)-4-(p-tolyl)-1,2,4-oxadiazole-5(4H)-thione at 166 degreesC. Copyright (C) 2000 John Wiley & Sons, Ltd.