(2,3,4,5,6-pentachlorophenyl) 2-cyanoacetate

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

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

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

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

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

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

Procedure: 17 g. (0.2 moles) of cyanoacetic acid are dissolved in 150 ml. of dichloromethane and 40 g. (0.2 moles) of dicyclohexylcarbodiimide and 52 g. (0.2 moles) of pentachlorophenol dissolved in 200 ml. of dichloromethane are added dropwise at room temperature. The mixture is stirred for 4 hours at room temperature. The mixture is cooled to 0° C. and the precipitated dicyclohexylcarbodiimide is filtered and the solvent is distilled off. The residue is taken up in diisopropyl ether, filtered and dried. The mixture is cooled to 0° C. the precipitated dicyclohexylcarbodiimide is filtered the solvent is distilled off filtered dried

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

Procedure: 8.5 g (0.1 mole) of cyano acetic acid are dissolved in 350 ml. of ethylether and cooled to 0° C. 20.1 g. (0.1 mole) of phosphorus pentachloride are added. The cooling is stopped and the temperature is slowly raised to room temperature. When the HCl evolution ceases the solvent is distilled off in vacuo. The residue containing the formed cyanoacetic acid chloride and phosphoroxychloride is taken up in 50 ml. of dichloromethane and 26 g. (0.1 mole) of pentachlorophenol and 11 ml. (0.1 mole) of N,N'-dimethylaniline are added dropwise in 300 ml. of dichloromethane. is distilled off in vacuo The residue containing the formed cyanoacetic acid chloride and phosphoroxychloride

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

Procedure: 17 g. (0.2 moles) of cyanoacetic acid are mixed thorougly with 53.2 g. (0.2 moles) of pentachlorophenol, and 19.0 ml. (0.2 moles) of phosphoroxychloride are added dropwise. The obtained mixture is heated slowly on an oil-bath, until the inner temperature rises to 85° to 90° C. and the solid melts under intensive evolution of HCl. The homogeneous melt is heated until the hydrochloric acid evolution ceases. In the meantime the first cyanoacetic acid pentachlorophenyl ester precipitate is obtained. When the hydrochloric acid evolution ceases, the system is cooled and dissolved in 500 ml. of dichloromethane, washed 3 times with 100 ml. of water, treated with decolorizing charcoal, dried and evaporated. Diisopropyl ether is added. Cyanoacetic acid pentachlorophenyl ester precipitates in the form of crystals. The obtained mixture is heated slowly on an oil-bath, until the inner temperature rises to 85° to 90° C.