An Approach to Pyrazoline-Fused Chlorins by Dipolar [3 + 2]-Cycloaddition of Iminonitriles to <i>meso</i>-Tetrakis(pentafluorophenyl)porphyrin: Synthesis of New PDT Photosensitizers
作者:Przemysaw Wyrebek、Stanisaw Ostrowski
DOI:10.1246/bcsj.20110408
日期:2012.10.15
meso-Tetrakis(pentafluorophenyl)porphyrin reacts at higher temperature with unstable iminonitriles (R–C≡N+–N−–Ar), affording pyrazoline-fused chlorins, according to dipolar [3 + 2]-cycloaddition pathway. The respective iminonitriles were in situ generated from the corresponding functionalized α-halogenohydrazine derivatives by 1,3-elimination of HX in the presence of base (NEt3, DABCO). This method allows synthesis of very attractive moieties which may be of potential use as sensitizers in photodynamic therapy (PDT).
间四(五氟苯基)卟啉在较高温度下与不稳定的亚氨基腈(R-C≡N+-N--Ar)发生反应,根据双极[3 + 2]-环加成途径生成吡唑啉融合的氯化物。在碱(NEt3、DABCO)存在下,通过 1,3- 消除 HX,从相应的官能化 α-卤代肼衍生物原位生成相应的亚硝酰亚胺。这种方法可以合成极具吸引力的分子,这些分子有可能用作光动力疗法(PDT)的敏化剂。