OPTICAL RESOLUTION OF ALPHAAISOPROPYLLPPCHLOROPHENYLLACETIC ACID

摘要

PURPOSE:To resoluve the title compound optically, by selectively crystallizing one optically active salt from the compound with a resolving reagent, e.g. alpha-phenyl- beta-rho-triethylamine, in a mixed solvent consisting of a hydrophobic, a hydrophilic organic solvents, and/or water. CONSTITUTION:alpha-Isopropyl-rho-chlorophenylacetic acid is resolved with an optically active alpha-phenyl-beta-rho-triethylamine or optically active alpha-phenylethylamine in a mixed solvent consisting of a hydrophobic organic solvent, e.g. toluene, a hydrophilic one, e.g. methyl alcohol, and/or water, to crystallize one of the opticall active salts selectively. The crystals are separated from the mother liquor, and resolved, if necessary, to give the objective compound. EFFECT:The optical purity of the (+) isomer, whose ester has a powerful insecticidal effect can be improved greatly by a small amount of solvents.