DOI: 10.1002/asia.202400029 ISSN: 1861-4728
Carbazole Based Smaragdyrins: Synthesis, Aromaticity Switching, and Formation of a Spiro‐Dimer
Jinchao Chen, Haigen Nie, Yutao Rao, Ling Xu, Mingbo Zhou, Bangshao Yin, Jianxin Song, Atsuhiro Osuka- General Chemistry
- Biochemistry
- Organic Chemistry
Carbazole‐incorporated smaragdyrin BF2‐complex 3 was synthesized by SNAr reaction of 3,5‐dibromo‐8‐mesityl‐BODIPY 1 with 3,6‐di(tert‐butyl)‐1,8‐di(pyrrol‐2‐yl)carbazole 2 as a nucleophile. Demetalation of 3 with ZrCl4 gave the corresponding smaragdyrin free base 4 in a good yield. Oxidations of 3 and 4 with MnO2 gave smaragdyrins 5 and 6, respectively, both followed by aromaticity switching, since the oxidized products showed a moderate paratropic ring current owing to their 20π‐electronic circuits. Further, treatment of 4 with [RhCl(CO)2]2 in the presence of NaOAc gave RhI complex 7, and oxidation of 3 with RuCl3 in the presence of triethylamine led to the formation of a spiro dimer product, 8.