One-pot synthesis of 2-bromo-3-hydroxybenzoates by the Diels–Alder reaction of furans with bromoalkyne and the subsequent ring-opening aromatization was studied by means of deuterium-labeling experiments. The residual protons in silica gel were considered to be the hydrogen source of the hydroxy group of products under the silica gel-promoted condition. The deuterium-labeling experiment revealed a rapid equilibrium among the intermediates prior to the aromatization under FeCl3-catalyzed condition.
通过
呋喃与
溴炔的戴尔斯-阿尔德反应及后续的开环芳构化,研究了2-bromo-3-hydroxybenzoates的单锅合成。
硅胶中的残余质子被视为产品中羟基的氢源,在
硅胶促进的条件下进行。
氘标记实验揭示了在FeCl3催化条件下,芳构化前的中间体之间存在快速平衡。