Colgate University, Department of Chemistry, 13 Oak Drive, Hamilton, New York 13346, USA.
J Org Chem. 2010 Feb 5;75(3):553-63. doi: 10.1021/jo902452c.
Two complementary dipyrromethane + dipyrromethanemonocarbinol routes to a meso-substituted 5-isocorrole were investigated. While both routes could afford the identical 5-isocorrole, self-condensation of the different dipyrromethanemonocarbinol precursors could potentially lead to a second porphyrinoid of different structure (a porphyrin or a porphodimethene). The two reaction routes were examined to compare the distribution of porphyrinoid products, probe the effect of key reaction parameters on the product distribution, and identify conditions for the efficient preparation of the 5-isocorrole so that its spectral properties and stability toward light and air could be assessed. For each route, a systematic survey of reaction parameters was performed via analytical-scale reactions monitored for the yields of the 5-isocorrole and self-condensation product by HPLC. The two reaction routes were found to afford very different product distributions in accordance with the anticipated nucleophilicity of the dipyrromethane and dipyrromethanemonocarbinol precursors. The most promising reaction condition (InCl(3), 0.32 mM) was performed on a preparative-scale providing the 5-isocorrole in an isolated yield of 31% (102 mg). Spectroscopic analysis was consistent with the 5-isocorrole structure. The stability of the 5-isocorrole in dilute solution upon exposure to light and air was assessed by UV-vis spectroscopy and HPLC and was found to be excellent.
研究了两种互补的二吡咯甲烷+二吡咯甲酮单甲醚途径来合成中取代的 5-异Corrole。虽然这两种途径都可以得到相同的 5-异 Corrole，但不同的二吡咯甲酮单甲醚前体的自缩合可能会导致另一种结构不同的卟啉类化合物（卟啉或卟吩二噻烯）。检查了这两种反应途径，以比较卟啉类产物的分布，探究关键反应参数对产物分布的影响，并确定有效制备 5-异 Corrole 的条件，以便评估其光谱性质和对光和空气的稳定性。对于每种途径，通过 HPLC 监测 5-异 Corrole 和自缩合产物的产率，对分析规模的反应进行了系统的反应参数调查。这两种反应途径的产物分布非常不同，这与预期的二吡咯甲烷和二吡咯甲酮单甲醚前体的亲核性一致。最有前途的反应条件（InCl(3)，0.32 mM）在制备规模上进行，5-异 Corrole 的分离产率为 31%（102 mg）。光谱分析与 5-异 Corrole 结构一致。通过紫外可见光谱法和 HPLC 评估了 5-异 Corrole 在稀溶液中暴露于光和空气中的稳定性，发现其稳定性非常好。
