Synthesis of oxametallacycles from 2-iodoethanol on Ag(111) and the structure dependence of their reactivity
Temperature-programmed desorption (TPD), high-resolution electron energy loss spectroscopy (HREELS), and density functional theory (DFT) were used to investigate the adsorption and reaction of 2-iodoethanol on the Ag(111) surface. When 2-iodoethanol is dosed onto Ag(111) at 150 K, it reacts to form a hydroxyethyl surface intermediate. The hydroxyethyl reacts at 255 K to form ethylene, acetaldehyde, and a surface oxametallacycle. This surface oxametallacycle reacts at 320 K to form acetaldehyde. Surface oxametallacycles and metallaoxetanes have been implicated as important intermediates in various heterogeneous and homogeneous chemical reactions. We focus on the investigation of the chemical structure and reactivity of the isolated oxametallacycle and compare the observations to previous results. We conclude that the oxametallacycle selectivity to different products is dependent on the oxametallacycle coordination geometry and is therefore influenced by the surface structure.