Method for synthesizing zirconium complex

A method for synthesizing a zirconium complex comprising:

• mixing
• a solvent containing an organic substance having a dipole moment of 3.0 D or more,
• a chelating agent solution in which a chelating agent containing a structure represented by General Formula (1) or General Formula (2) is dissolved, and
• zirconium dissolved in an acidic solution, to obtain a mixed solution;
• and
• setting the mixed solution at a predetermined temperature or more to synthesize a zirconium complex,
• wherein a concentration of the organic substance is 50 vol % or more and 95 vol % or less,
• wherein in General Formula (1):
• R1, R2, R3, and R4 being each a hydrogen (—H) (in this case, none of R5 to R12 is further connected), a —CH— group, —(CH2),CH— group, a —C(═O) (CH2),CH— group, or a —(CH2) C(═O)N-group;
• n being an integer of 0 or more;
• at least two of R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, R19, and R20 being at least two selected from a carboxylic acid, a primary amide, hydroxamic acid, phosphonic acid, phosphoric acid, sulfonic acid, an alcohol, an amine, phenol, aniline, and an ester, a secondary amide, and a phosphate that are each obtained by adding a substituent to the aforementioned, with the residual substituents being each a hydrogen, an alkyl chain, a tert-butyl blocked carboxylic acid, nitrobenzene, or a substituent-added alkyl chain;
• a positron emission tomography (PET) probe or a functional group facilitating bonding of a PET probe being optionally added to a functional group contained in R5 to R20;
• the functional group facilitating bonding being a carboxylic acid, a succinimide carboxylate, a tetrafluorophenol carboxylate, an alcohol, an amine, a thiol, isothiocyanate, maleimide, phenol, aniline, benzoic acid, phenyl isothiocyanate, or an alkyne, an azide, dibenzocyclooctyne (DBCO), bicyclononyne (BCN), trans-cyclooctene (TCO), norbornene, tetrazine, or methyltetrazine, which are each a click chemistry reagent;
• and
• R1 to R20 optionally having a structure of the functional group facilitating bonding or a condensed structure of a PET probe and the functional group facilitating bonding, and
• wherein in General Formula (2):
• R21, R22, and R23 being each a hydrogen (—H) (in this case, none of R24 to R29 is further connected), a —CH— group, —(CH2),CH— group, a —C(═O) (CH2),CH— group, or a —(CH2) C(═O)N-group;
• n being an integer of 0 or more;
• at least two of R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, and R35 being at least two selected from a carboxylic acid, a primary amide, hydroxamic acid, phosphonic acid, phosphoric acid, sulfonic acid, an alcohol, an amine, phenol, aniline, and an ester, a secondary amide, and a phosphate that are each obtained by adding a substituent to the aforementioned, with the residual substituents being each a hydrogen, an alkyl chain, a tert-butyl blocked carboxylic acid, nitrobenzene, or a substituent-added alkyl chain;
• a PET probe or a functional group facilitating bonding of a PET probe being optionally added to a functional group contained in R24 to R35;
• the functional group facilitating bonding being the following functional group, a carboxylic acid, a succinimide carboxylate, a tetrafluorophenol carboxylate, an alcohol, an amine, a thiol, isothiocyanate, maleimide, phenol, aniline, benzoic acid, phenyl isothiocyanate, or an alkyne, an azide, DBCO, BCN, TCO, norbornene, tetrazine, or methyltetrazine, which are each a click chemistry reagent;
• and
• R24 to R35 optionally having a structure of the functional group facilitating bonding or a condensed structure of a PET probe and the functional group facilitating bonding, and
• wherein the organic substance is at least one substance selected from the group consisting of dimethylsulfoxide (DMSO), N,N-dimethylformamide (DMF), N-methylformamide (NMF), N-methylpyrrolidone (NMP), and urea.