Planar Subporphyrin Borenium Cations
datasetposted on 10.08.2011, 00:00 by Eiji Tsurumaki, Shin-ya Hayashi, Fook S. Tham, Christopher A. Reed, Atsuhiro Osuka
Subporphyrin borenium cations with a carborane counterion have been prepared by treatment of B-methoxy subporphyrins with the silylium reagent Et3Si(CH6B11Br6). In contrast to the distinctly domed subphthalocyanine borenium cation, a nearly planar structure with sp2 hybridized boron is found in the X-ray structure of the triphenylsubporphyrin borenium cation. The cations exhibit absorption and fluorescence spectra that are quite similar to those of B-methoxy subporphyrins. B-phenyl subporphyrins were prepared in good yield by reaction of subporphyrin borenium cations with phenyllithium.