[Science Advances] 我室夏海平教授发表论文:Constraint of a ruthenium-carbon triple bond to a five-membered ring

我室夏海平教授在 Science  Advances 上发表论文:Constraint of a ruthenium-carbon triple bond to a five-membered ring

文章链接:http://advances.sciencemag.org/content/4/6/eaat0336?_ga=2.3303416.954969183.1530175603-1825617020.1503620062

摘要:

The incorporation of a metal-carbon triple bond into a ring system is challenging because of the linear nature of triple bonds. To date, the synthesis of these complexes has been limited to those containing third-row transition metal centers, namely, osmium and rhenium. We report the synthesis and full characterization of the first cyclic metal carbyne complex with a second-row transition metal center, ruthenapentalyne. It shows a bond angle of 130.2(3)° around the sp-hybridized carbyne carbon, which represents the recorded smallest angle of second-row transition metal carbyne complexes, as it deviates nearly 50° from the original angle (180°). Density functional theory calculations suggest that the inherent aromatic nature of these metallacycles with bent Ru≡C–C moieties enhances their stability. Reactivity studies showed striking observations, such as ambiphilic reactivity, a metal-carbon triple bond shift, and a [2 + 2] cycloaddition reaction with alkyne and cascade cyclization reactions with ambident nucleophiles.