(焦)脱镁叶绿酸-a的1,3-偶极环加成反应及其叶绿素类二氢卟吩的合成

1,3-Dipolar Cycloadditions of(Pyro)pheophorbide-a and Synthesis of Chlorophyllous Chlorin Derivatives

以脱镁叶绿酸-a甲酯为起始原料,通过加成、缩合和空气氧化等常见化学反应,在二氢卟吩色基上构建了新的碳碳双键;选择不同的1,3-偶极体与3-位、12-位和外接环烯键进行1,3-偶极环加成反应,完成了一系列具有五元杂环取代的叶绿素类二氢卟吩衍生物的合成,其化学结构均经UV-Vis、IR、MS、1H NMR及元素分析予以证实,并对1,3-偶极环加成反应的区域选择性及其相应的反应机理进行了讨论.

Pheophorbide-a methyl ester was used as a starting material, and new carbon-carbon double bonds were built on the chlorin chromophore by addition, condensation and allomerization. 1,3-Dipolar cycloadditions with different 1,3-dipols for the olefinic bonds at 3-position, 12-position and exocyclic E-ring were performed to synthesize a series of chlorophyllous chlorin derivatives substituted with five-membered heterocycle. The chemical structures of the unreported chlorins were char-acterized by UV-Vis, 1H NMR, IR, MS and elemental analysis. The region selectivity of 1,3-dipolar cycloadditions and corre-sponding reaction mechanisms were also discussed.