VERFAHREN ZUR HERSTELLUNG VON 3,5-DICHLOR-2,4-DIFLUORNITROBENZOL.

摘要

3.5-Dichloro-2,4-difluoro-nitrobenzene (I) is prepd. by reacting 2,3,4,5-tetrachlor-nitrobenzene with a fluoride of an alkali metal, in DMSO or a mixt. contg. DMSO, at 60-160 deg.C during 20-0.2h. Temp. and time are connected by the equation T(deg.C) = A-33 log t(h), where A = 100-137. Reaction is pref. at 80-140 (95-125) deg.C, in DMSO alone, with KF, esp. not pretreated, as the alkali fluoride. The value of A is 110-135 (115-130). The prod. is extracted from the DMSO or mixt. by an open-chain or cyclic, pref. satd., aliphatic hydrocarbon with b.pt. at least 30 deg.C, and is sepd. physically from the extractant.