Department of Chemistry, Graduate School of Science, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka, 558-8585, Japan.
Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, Hyogo, 657-8501, Japan.
Chem Asian J. 2023 Feb 14;18(4):e202201210. doi: 10.1002/asia.202201210. Epub 2023 Jan 13.
The C-H alkenylation of N-acetylcarbazoles proceeds smoothly at the C1-position in the presence of a cationic Cp*Rh(III) catalyst to produce 1-alkenylcarbazoles. The use of a cationic Cp Rh(III) catalyst enables further alkenylation to give 1,8-dialkenylcarbazoles. The direct alkenylation procedure in combination with the ready removal of the acetyl directing group provides a straightforward synthetic pathway to 1- and/or 8-alkenyl-N-H-carbazole derivatives. One of 1-alkenyl-N-H-carbazoles obtained by the present C-H alkenylation/deacetylation exhibits solvatochromism.
N-乙酰咔唑的 C-H 烯丙基化反应在阳离子 Cp*Rh(III)催化剂的存在下在 C1 位顺利进行，生成 1-烯基咔唑。使用阳离子 Cp Rh(III)催化剂可以进一步进行烯丙基化反应，得到 1,8-二烯基咔唑。直接烯丙基化反应与乙酰基导向基团的易于去除相结合，为 1-和/或 8-烯基-N-H-咔唑衍生物提供了一条直接的合成途径。通过本 C-H 烯丙基化/脱乙酰基反应得到的 1-烯基-N-H-咔唑中的一种表现出溶剂化变色。
