Study On The Synthesis Of Nitro Derivatives Chlorobenzotrifluoride

The nitro-derivates of p-chlorotrifluoromethylbenzene were important intermediates of finechemical industry and Pharmaceuticals. They were important raw material for manufacture of medicines, agrochemicals, dyes and so on. Synthesis of nitro-derivates of p-chlorotrifluoromethylbenzene was significant to promote the development of correlative industries of our country and satisfy the requirement of the international market.3-nitro-4-chlorotrifluoromethylbenzene (Ⅰ) had been synthesized via the first nitration step of p-chlorotrifluoromethylbenzene with nitro-sulfuric acid. The reaction conditions recommended was n(C₆H₄ClCF₃) : n(HNO₃) : n(H₂SO₄)= 1: 1.1 :4.4, the adding temperature was about 0～15℃, then reacting at 35℃for 1.0h, and the yield was above 96%; 3,5-dinitro-4-chlorotrifluoromethylbenzene (Ⅱ) had been synthesized via the second nitration step of (Ⅰ) with nitro-sulfuric acid. The optimum reaction conditions was n(C₆H₃ClCF₃NO₂): n(HNO₃): n(H₂SO₄)=1:5.5:22, adding (Ⅰ) into the mixed nitro-sulfuric acid at the temperature about 15～25℃, then reacting at 110℃for 5.5h, and the yield was about 72%.Due to the activity of chlorine substituting group, 2,2^',6,6^'-tetranitro-4,4^'-ditrifluoromethyl-biphenyl had been prepared from (Ⅱ) via Ullmann coupling reaction, with the yield up to 71.8%; 4-N,N-diethyl-3,5-dinitro-(trifluoromethyl)benzenamine had been prepared from (Ⅱ) reacted with diethylamine in the emulsion, received 72.9%; 7-(2,6-dinitro-4-trifluoromethyl)phenoxycoumarin had been achieved from (Ⅱ) reacted with umbelliferone in the emulsion, received about 35%. All of the four nitro-derivates of p-chlorotrifluoromethylbenzene presented a very promising future in practical applications. The target compounds had been confirmed with melting point,¹HNMR,elemental analyses,GC-MS and so on.