1,2-dichloro-3-(3,3,3-trifluoroprop-1-ynyl)benzene

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 23.9 g of 2,3-dichloro-(3,3,3-trifluoropropyn-1-yl)-benzene and 15.6 g of N-(2-cyanoethyl)-N-formylglycine are dissolved in 100 ml of acetic anhydride, and the solution is refluxed for 24 h. The mixture is concentrated by evaporation under reduced pressure; the residue is then taken up in toluene, and purified by chromatography through silica gel. The solvent is evaporated off, and from the eluate is obtained 1-(2-cyanoethyl)-3-(2,3-dichlorophenyl)-4-trifluoromethylpyrrole, m.p. 83°-85° C. from ether/hexane (compound No. 3.28). the solution is refluxed for 24 h The mixture is concentrated by evaporation under reduced pressure purified by chromatography through silica gel The solvent is evaporated off

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 31.7 g of (2-chloro-3,3,3-trifluoropropen-1-yl)-2,3-dichlorobenzene in 50 ml of tert-butanol, there is added dropwise at RT a solution of 14.1 g of potassium tert-butylate in 750 ml of tert-butanol in such a manner that the temperature of the reaction solution does not exceed 30° C. After continued stirring at RT for 18 h, the mixture is taken up in ice-water and extracted with ether. The organic phases are combined, washed with water and sodium chloride solution, and concentrated by evaporation. There is thus obtained, after distillation in vacuo, 2,3-dichloro-(3,3,3-trifluoropropyn-1-yl)-benzene in the form of colourless oil, b.p. 92°-98° C. at 22 mb (compound No. 2.27). does not exceed 30° C extracted with ether washed with water and sodium chloride solution concentrated by evaporation There is thus obtained after distillation in vacuo, 2,3-dichloro-(3,3,3-trifluoropropyn-1-yl)-benzene in the form of colourless oil, b.p. 92°-98° C. at 22 mb (compound No