Synthesis of π-Extended Carbazole Dimers via Oxidative Cyclization Using DDQ and Sulfonic Acid and Elucidation of the Reaction Mechanism

Tetsuo Iwanaga, Tomohiro Oki, Yoshihiro Morioka, Shoichiro Inoue, Hiroyasu Sato

This paper describes the synthesis of various π-extended carbazole dimers via intramolecular oxidative cyclization using a chain precursor consisting of two carbazole units bridged by a nitrogen atom. A careful selection of the reaction conditions using 2,3-dichloro-5,6- dicyano-p-benzoquinone/sulfonic acid enabled the selective synthesis of a π-extended analogue with an angular (L-shape) structure in moderate yield. The preferential positions for the bonding of the two carbazole units in this π-extended derivative were determined by performing density functional theory calculations.

The Journal of Organic Chemistry

ACS

87

21

14855

14860

https://doi.org/10.1021/acs.joc.2c01571

https://pubs.acs.org/doi/10.1021/acs.joc.2c01571