A Two‐Coordinate Cyclic (Alkyl)(amino)silylene: Balancing Thermal Stability and Reactivity. (15th November 2016)

• Record Type: Journal Article
• Authors: Kosai, Tomoyuki; Ishida, Shintaro; Iwamoto, Takeaki
• Is Part Of: Angewandte Chemie. Volume 128:Number 50(2016)
• Page Start: 15783
• Page End: 15787
• Publication Date: 2016-11-15
• Subjects: Carbene -- Photochemie -- Röntgenbeugung -- Silicium -- Strukturaufklärung; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201608736
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: A crystalline two‐coordinate cyclic (alkyl)(amino)silylene (1 ) was successfully synthesized and isolated. Its 29 Si NMR and UV/Vis spectra indicate that the electronic properties of1 fall between those of cyclic dialkylsilylenes and diaminosilylenes. At very low temperature, the color of a solution of1 turned from colorless to yellow, which was monitored by UV/Vis spectroscopy. DFT calculations supported the hypothesis that head‐to‐head dimers (disilenes) with a very long Si–Si distance are formed at such low temperatures. Although1 is thermally stable, it readily undergoes cycloadditions, Si−H insertions, and photochemical reactions with benzene similar to dialkylsilylenes. At higher temperatures, 1 is also susceptible to intermolecular benzylic C−H insertion reactions, as well as unprecedented dehydrogenation reactions with cyclohexa‐1, 4‐diene and 9, 10‐dihydroanthracene to afford benzene and anthracene, respectively.