Reactions of 1-Fluoro-2,4-dinitrobenzene with ambident thiocyanate ion

Abstract

The reactions of potassium thiocyanate with 1-fluoro-2,4-dinitrobenzene are not catalysed by thorium nitrate and give no more than 1% 2,4-dinitrothiocyanatobenzene in methanol, and no more than 0.1% in dimethylformamide. The major product is 2,4,2',4'-tetranitrodiphenyl sulphide. The S_NAr intermediate complex is shown to decompose in an abnormal way and evidence for its existence is presented. The ambident thiocyanate ion attacks 1-fluoro-2,4-dinitrobenzene 67% through sulphur and 33% through nitrogen in both methanol and dimethylformamide and in the presence and absence of thorium nitrate.