2.6- Dichlorobenzal chloride

Dichlorobenzal chloride is used ia the manufacture of 2,6-dichlorobenzaldehyde and 2,6-dichlorobenzonitrile (77). With the exception of certain products used ia the manufacture of herbicides, the volume of iadividual compounds produced is small, amounting to no more than several hundred tons annually for any iadividual compouad. 

Hydrolysis of 2,6-dichlorobenzal chloride is much more difficult than that of benzal chloride itself. In contrast to the latter, 2,6-dichloro-benzal chloride is not hydrolyzed either by water and iron or by calcium or potassium hydroxide, even under pressure at 150°C. The hydrolysis to the desired aldehyde is effected with concentrated sulfuric acid, although a considerable portion of the product is resinified in the process. 

A mixture of 100 grams of 2,6-dichlorobenzal chloride and 200 grams of 66° sulfuric acid is stirred for 12 hours at 55°. The mixture is then diluted with 1 liter of water, and the product is separated from the dililte... 

J361 to over 5700, mw — 38000—600000, colorl, amorph or cryst, mp 240—250°, d (amorph) 1.04—1.065g/cc RI 1.59—1.60. Sol in CCI4, et benz, tol, et acet, benz, methyl et ketone, chlf, tetrahydrofuran, methyl isobutyl ketone, methylene chloride, o-dichlorobenz, py and cyclohexane. Styrene polymer can be prepd in many ways. The simplest procedure is that of heating the pure monomer. The general reaction can be represented as ... 

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