Triazidation of 2,4,6-trifluorobenzenes

1,3,5-Trichloro-2,4,6-trifluorobenzene and 1-bromo-3,5-dichloro-2,4,6-trifluorobenzene undergo selective defluorination on heating in dimethylsulfoxide with sodium azide to form 1,3,5-triazido-2,4,6-trichlorobenzene and 1,3,5-triazido-2-bromo-4,6-dichlorobenzene in high yields. The azidation of 1,3,5-tribromo-2,4,6-trifluorobenzene under similar reaction conditions leads to the mixture of 1,3-diazido-2,4,6-tribromo-5-fluorobenzne and 1,3,5-triazido-2,4,6-tribromobenzene in the 1:2 ratio, respectively. 1,3,5-Triazido-2,4,6-tribromobenzene can be obtained as a sole product in high yield if the azidation of 1,3,5-tribromo-2,4,6-trifluorobenzene with sodium azide is carried out in aqueous acetone. The triazides obtained are the first readily available 1,3,5-triazidobenzenes that may find a wide practical use as new photoactive cross-linking reagents for polymer chemistry and as starting compounds in organic synthesis and photochemical preparation of new organic magnetic materials.