The object is to prevent deterioration and loss of dicyanobenzene in producing dicyanobenzene by ammoxidation of xylene to thereby achieve industrial and economical advantage in producing of dicyanobenzene. The method for producing dicyanobenzene of the present invention includes: contacting a xylene-ammoxidation reaction gas containing dicyanobenzene in ammoxidation of xylene with an organic solvent so as to obtain a dicyanobenzene-absorbing solution; contacting the dicyanobenzene-absorbing solution with a basic aqueous solution containing a salt such as ammonium carbonate so as to extract a water-soluble salt formed by neutralization reaction between carboxylic acid in the dicyanobenzene-absorbing solution and a base in the basic aqueous solution into an aqueous phase; separating the mixture of the dicyanobenzene-absorbing solution and the basic aqueous solution into an organic phase and an aqueous phase; decomposing the salt such as ammonium carbonate contained in the organic phase for separation of the salt from the organic phase; and distilling the organic phase to separate low boiling point compounds contained in the organic phase from the organic phase so as to obtain dicyanobenzene.

The purification method of an aldehyde compound of the present invention includes a step of neutralizing a reaction solution containing an aldehyde compound by adding water and a base compound to the reaction solution, and a step of distilling the neutralized reaction solution, in which the reaction solution is obtained by reacting a compound represented by the following Formula (a1) or (a2) with hydrogen and carbon monoxide in the presence of a metal compound of groups 8 to 10 and a phosphorus compound, the phosphorus compound is represented by Formula (R.sup.1O).sub.3P, and the base compound is at least one kind selected from among carbonate and hydrogen carbonate of metals of group I on the periodic table and carbonate and hydrogen carbonate of metals of group II on the periodic table. ##STR00001##

The purification method of an aldehyde compound of the present invention includes a step of neutralizing a reaction solution containing an aldehyde compound by adding water and a base compound to the reaction solution, and a step of distilling the neutralized reaction solution, in which the reaction solution is obtained by reacting a compound represented by the following Formula (a1) or (a2) with hydrogen and carbon monoxide in the presence of a metal compound of groups 8 to 10 and a phosphorus compound, the phosphorus compound is represented by Formula (R.sup.1O).sub.3P, and the base compound is at least one kind selected from among carbonate and hydrogen carbonate of metals of group I on the periodic table and carbonate and hydrogen carbonate of metals of group II on the periodic table. ##STR00001##

A method is provided to purify [F-18]FEONM under a high pressure. The synthesis processes of [F-18]FEONM are integrated. An isolation process of non-toxic radio-high performance liquid chromatography (radio-HPLC) is used to purify the crude product. The method integrates a convention [F-18]FDG synthesizer and a novel radio-HPLC system together in a heat chamber. After radiofluorinating the precursor, the reaction product is purified with an alumina solid-phase column in advance to obtain the crude product while fluorine-18 is removed. Then, diphenyl semipreparative HPLC column is used for a final purification. A non-toxic solvent is used for mobile-phase eluting to remove the unreacted precursor and the phase-transfer solvent. The radiofluorination has a reaction yield about 50 percent (%). The method has an uncorrected radiochemical yield of 10˜20%. Both of the radio-HPLC and the radio-thin layer chromatography (radio-TLC) have radiochemical purity higher than 95%.

A method is provided to purify [F-18]FEONM under a high pressure. The synthesis processes of [F-18]FEONM are integrated. An isolation process of non-toxic radio-high performance liquid chromatography (radio-HPLC) is used to purify the crude product. The method integrates a convention [F-18]FDG synthesizer and a novel radio-HPLC system together in a heat chamber. After radiofluorinating the precursor, the reaction product is purified with an alumina solid-phase column in advance to obtain the crude product while fluorine-18 is removed. Then, diphenyl semipreparative HPLC column is used for a final purification. A non-toxic solvent is used for mobile-phase eluting to remove the unreacted precursor and the phase-transfer solvent. The radiofluorination has a reaction yield about 50 percent (%). The method has an uncorrected radiochemical yield of 10˜20%. Both of the radio-HPLC and the radio-thin layer chromatography (radio-TLC) have radiochemical purity higher than 95%.

Provided is a method of preparing an acrylonitrile dimer, the method including: supplying an acrylonitrile monomer, a phosphorus-based catalyst, an alcohol solvent, and an ionic liquid to a reactor to perform a dimerization reaction to prepare a single-phase dimerization reaction product (S10); supplying a reactor discharge stream including the dimerization reaction product to a first distillation column, separating the alcohol solvent and an unreacted acrylonitrile monomer from an upper discharge stream, and supplying a lower discharge stream including an acrylonitrile dimer, the ionic liquid, and the phosphorus-based catalyst to a second distillation column (S20); and separating an upper discharge stream including the acrylonitrile dimer and separating a lower discharge stream including the ionic liquid and the phosphorus-based catalyst, from the second distillation column (S30).

Provided is a method of preparing an acrylonitrile dimer, the method including: supplying an acrylonitrile monomer, a phosphorus-based catalyst, an alcohol solvent, and an ionic liquid to a reactor to perform a dimerization reaction to prepare a single-phase dimerization reaction product (S10); supplying a reactor discharge stream including the dimerization reaction product to a first distillation column, separating the alcohol solvent and an unreacted acrylonitrile monomer from an upper discharge stream, and supplying a lower discharge stream including an acrylonitrile dimer, the ionic liquid, and the phosphorus-based catalyst to a second distillation column (S20); and separating an upper discharge stream including the acrylonitrile dimer and separating a lower discharge stream including the ionic liquid and the phosphorus-based catalyst, from the second distillation column (S30).

Provided is a method of preparing an acrylonitrile dimer, the method including: supplying an acrylonitrile monomer, a phosphorus-based catalyst, an alcohol solvent, and an ionic liquid to a reactor to perform a dimerization reaction to prepare a single-phase dimerization reaction product (S10); supplying a reactor discharge stream including the dimerization reaction product to a first distillation column, separating the alcohol solvent and an unreacted acrylonitrile monomer from an upper discharge stream, and supplying a lower discharge stream including an acrylonitrile dimer, the ionic liquid, and the phosphorus-based catalyst to a second distillation column (S20); and separating an upper discharge stream including the acrylonitrile dimer and separating a lower discharge stream including the ionic liquid and the phosphorus-based catalyst, from the second distillation column (S30).

A preparation method of 1-(4-aminophenyl)cyclopentanecarbonitrile includes the following steps: step 1: in the presence of Li.sub.2CuCl.sub.4, adding a nitrochlorobenzene-zinc reagent dropwise to a 1-chlorocyclopentanecarbonitrile solution to prepare a compound 1-(4-nitrophenyl)cyclopentanecarbonitrile; and step 2: subjecting the compound 1-(4-nitrophenyl)cyclopentanecarbonitrile obtained in step 1 to a nitroreduction reaction under the action of a catalyst to prepare the compound 1-(4-aminophenyl)cyclopentanecarbonitrile. The preparation method involves cheap and easily-available raw materials, mild reaction conditions, and convenient operations, leads to high yield, and is environmentally-friendly and suitable for industrial large-scale production.

A preparation method of 1-(4-aminophenyl)cyclopentanecarbonitrile includes the following steps: step 1: in the presence of Li.sub.2CuCl.sub.4, adding a nitrochlorobenzene-zinc reagent dropwise to a 1-chlorocyclopentanecarbonitrile solution to prepare a compound 1-(4-nitrophenyl)cyclopentanecarbonitrile; and step 2: subjecting the compound 1-(4-nitrophenyl)cyclopentanecarbonitrile obtained in step 1 to a nitroreduction reaction under the action of a catalyst to prepare the compound 1-(4-aminophenyl)cyclopentanecarbonitrile. The preparation method involves cheap and easily-available raw materials, mild reaction conditions, and convenient operations, leads to high yield, and is environmentally-friendly and suitable for industrial large-scale production.