| 摘要 |
PROBLEM TO BE SOLVED: To provide an entirely new method for producing a phthalide compound, different from the conventional method by carrying out a dehydrogenation reaction of a specific triphenylmethane compound with a hydrogen receptor in the presence of a dehydrogenation catalyst. SOLUTION: (A) A triphenylmethane compound of formula I (R<1> to R<6> are each an alkyl, or R<1> and R<2> , R<3> and R<4> , and R<5> and R<6> form heterocycles by mutually binding each other with nitrogen atoms) (e.g. 2-[4,4'-bis(dimethylamino) benzhydryl]-5-dimethylaminobenzoic acid) is subjected to a dehydrogenation reaction with (B) a hydrogen receptor (e.g. nitrobenzene) in an amount of about five molar times as much as the amount of the component A in the presence of (C) a dehydrogenation catalyst (e.g. a platinum/carrier catalyst) in 0.0001-1 molar ratio to the component A preferably in a solvent and preferably in the presence of an insert gas at a temperature of 80-150 deg.C to provide the objective phthalide compound [e.g. 3,3-bis(4-dimethylaminophenyl)-6- dimethylaminophthalide]. |
