Bruce Alexandra M, Weyburne Emily S, Engle James T, Ziegler Christopher J, Geier G Richard
Colgate University , Department of Chemistry, 13 Oak Drive, Hamilton, New York 13346, United States.
J Org Chem. 2014 Jun 20;79(12):5664-72. doi: 10.1021/jo5008256. Epub 2014 Jun 11.
Phlorins bearing different substituents at the sp(3)-hybridized meso-position were investigated. The extent to which different substituents at this unique position can influence phlorin spectroscopic properties, structure, and stability is of interest given that such substituents are not in direct conjugation with the phlorin macrocycle. While the effect of various substituents at the sp(2)-hybridized positions has been the subject of prior investigations, the impact of different substituents at the saturated carbon atom has not been systematically examined. In this study, phlorins with different combinations of geminal methyl and phenyl substituents were prepared in yields of 24-49% via dipyrromethane + dipyrromethanedicarbinol routes, and their NMR spectra, UV-vis spectra, X-ray crystal structures, and stability toward light and air were compared. The nature of the substituents at the sp(3)-hybridized position was found to impact spectroscopic properties, structure, and stability to varying degrees. Thus, the choice of substituents at the sp(3)-hybridized meso-position provides a further option for altering phlorin properties.
对在sp(3)杂化的中位带有不同取代基的卟吩进行了研究。鉴于这些取代基不与卟吩大环直接共轭，此独特位置上不同取代基对卟吩光谱性质、结构和稳定性的影响程度备受关注。虽然之前的研究聚焦于sp(2)杂化位置上各种取代基的影响，但饱和碳原子上不同取代基的影响尚未得到系统研究。在本研究中，通过二吡咯甲烷+二吡咯甲烷二羧酸醇路线制备了具有不同偕二甲基和苯基取代基组合的卟吩，产率为24 - 49%，并比较了它们的核磁共振光谱、紫外可见光谱、X射线晶体结构以及对光和空气的稳定性。发现sp(3)杂化位置上取代基的性质在不同程度上影响光谱性质、结构和稳定性。因此，在sp(3)杂化中位选择取代基为改变卟吩性质提供了进一步的选择。
