METHOD FOR ISOLATING 4-NITROTOLUENE

FIELD: organic chemistry, chemical technology. ^ SUBSTANCE: invention relates to an improved method for isolation of 4-nitrotolunene used as raw for synthesis of dyes, high-strength fibers, toluylene diisocyanates, novocain and biologically active substances. Invention describes a method for isolation of 4-nitrotoluene from a mixture of isomers of mononitrotoluene by freezing out method wherein freezing out is carried out from mononitrotoluene isomers mixture, from nitrotoluenes mixture containing up to 20% of dinitrotoluenes in the presence of organic solvent, preferably, isopropyl alcohol or its azeotrope with water. Proposed method provides preparing the end product with the yield up to 42% and purity above 98%. ^ EFFECT: improved isolation method. ^ 1 tbl