One-Pot Synthesis of Hypervalent Diaryl(iodo)bismuthanes from<i> o</i>-Carbonyl Iodoarenes by Zincation
作者:Toshihiro Murafuji、A. F. M. Hafizur Rahman、Daiki Magarifuchi、Masahiro Narita、Isamu Miyakawa、Katsuya Ishiguro、Shin Kamijo
DOI:10.1155/2019/2385064
日期:2019.2.27
Diaryl(iodo)bismuthanes possessing a hypervalent C=O•••Bi–I bond were conveniently synthesized in a one-pot reaction by using arylzinc reagents generated from o-carbonyl iodobenzenes and zinc powder under ultrasonication. This method is superior to the conventional organolithium and Grignard methods because it has a wide functional group tolerance, requires no protecting group manipulations, and proceeds
Hypervalent bond formation has been found to occur at bismuth as the hypervalent center. The transformation of (2-acetylphenyl)bis(4-methylphenyl)bismuthane (2b) to (2-acetylphenyl)bromo(4-methylphenyl)bismuthane (3b) brings about a noticeable change in the electronic nature of the carbonyl function in the 2-acetylphenyl group, which is sensitively reflected in the IR, H-1, and C-13 NMR spectra of compound 3b. These spectral changes may be rationalized in terms of the formation of a hypervalent O-Bi-Br bond through intramolecular coordination of the carbonyl oxygen atom to the bismuth center. X-ray crystallography of 3b has confirmed this interpretation.