Tsuda A, Osuka A
Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
Science. 2001 Jul 6;293(5527):79-82. doi: 10.1126/science.1059552.
Scandium(III)-catalyzed oxidation of meso-meso-linked zinc(II)-porphyrin arrays (up to dodecamers) with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) led to efficient formation of triply meso-meso-, beta-beta-, and beta-beta-linked zinc(II)-oligoiporphyrins with 62 to 91% yields. These fused tape-shaped porphyrin arrays display extremely red-shifted absorption bands that reflect extensively pi-conjugated electronic systems and a low excitation gap. The lowest electronic absorption bands become increasingly intensified and red-shifted upon the increase in the number of porphyrins and eventually reach a peak electronic excitation for the dodecamer at approximately 3500 wavenumber. The one-electron oxidation potentials also decreased progressively upon the increase in the number of porphyrins. These properties in long and rigid molecular shapes suggest their potential use as molecular wires.
钪(III)催化的内消旋-内消旋连接的锌(II)-卟啉阵列（高达十二聚体）与2,3-二氯-5,6-二氰基-1,4-苯醌(DDQ)反应，以62%至91%的产率高效形成了三重内消旋-内消旋、β-β和β-β连接的锌(II)-寡聚卟啉。这些融合的带状卟啉阵列显示出极红移的吸收带，这反映了广泛的π共轭电子系统和低激发能隙。随着卟啉数量的增加，最低电子吸收带变得越来越强且红移，最终在约3500波数处达到十二聚体的峰值电子激发。随着卟啉数量的增加，单电子氧化电位也逐渐降低。这些长而刚性的分子形状的特性表明它们有作为分子导线的潜在用途。
