Derivatives of phenyl tribromomethyl sulfone as novel compounds with potential pesticidal activity

Krzysztof M Borys,Zbigniew Ochal,Maciej D Korzyński

doi:10.3762/bjoc.8.27

Abstract

A halogenmethylsulfonyl moiety is incorporated in numerous active herbicides and fungicides. The synthesis of tribromomethyl phenyl sulfone derivatives as novel potential pesticides is reported. The title sulfone was obtained by following three different synthetic routes, starting from 4-chlorothiophenol or 4-halogenphenyl methyl sulfone. Products of its subsequent nitration were subjected to the SNAr reactions with ammonia, amines, hydrazines and phenolates to give 2-nitroaniline, 2-nitrophenylhydrazine and diphenyl ether derivatives. Reduction of the nitro group of 4-tribromomethylsulfonyl-2-nitroaniline yielded the corresponding o-phenylenediamine substrate for preparation of structurally varied benzimidazoles.

Highlights

The rapid growth of the world population results in a continous increase in the demand for food
The results of our previous research revealed that the presence of halogenmethylsulfonyl groups in some nitroaniline and benzimidazole derivatives was beneficial to their herbicidal and fungicidal activity [6,8,9]
Our initial synthetic efforts were aimed at the preparation of the starting compound 4-halogenphenyl tribromomethyl sulfone. 4-Chlorophenyl tribromomethyl sulfone (1) was obtained by following three different synthetic methods (Scheme 2)

Summary

Introduction

The rapid growth of the world population results in a continous increase in the demand for food. The results of our previous research revealed that the presence of halogenmethylsulfonyl groups in some nitroaniline and benzimidazole derivatives was beneficial to their herbicidal and fungicidal activity [6,8,9]. We report the synthesis of novel aromatic compounds containing a tribromomethylsulfonyl group, including derivatives of nitroaniline, nitrophenylhydrazine, diphenyl ether and benzimidazole (Scheme 1). Our initial synthetic efforts were aimed at the preparation of the starting compound 4-halogenphenyl tribromomethyl sulfone (where halogen stands for chlorine or bromine).

Results

Conclusion