Regioselective Multicomponent Synthesis of 2,4,6-Trisubstituted Phenols from Fischer Alkynyl Carbene Complexes
作者:Julio López、Fabiola N. de la Cruz、María Inés Flores-Conde、Marcos Flores-Álamo、Francisco Delgado、Joaquín Tamariz、Miguel A. Vázquez
DOI:10.1002/ejoc.201501211
日期:2016.3
regioselectively prepared under mild conditions in high yields by treatment of a series of stable chromium(0) and tungsten(0) Fischer dienyl carbenes 4a–4g with different terminal alkynes 3a–3l. Carbenes 4a–4g were prepared by a [4+2] cycloaddition of alkynylethoxy carbene complexes 1a–1g with 1,2,3,4,5-pentamethylcyclopentadiene (2). In a complementary route, compounds 5a–5q were also obtained by
在温和的酸性条件下,受阻三环醇 6a-6q 通过逆狄尔斯-阿尔德反应制备了一系列 2,4,6-三取代酚 7a-7p,产率中等至良好(23-77%)。三环醇是通过将高度官能化的环己二烯酮 5a-5q 还原而获得的,而这些环己二烯酮是在温和条件下通过区域选择性地高产率地通过处理一系列稳定的铬(0)和钨(0)费歇尔二烯卡宾 4a-4g 与不同的末端炔烃 3a–3l。卡宾 4a-4g 是通过炔基乙氧基卡宾配合物 1a-1g 与 1,2,3,4,5-五甲基环戊二烯 (2) 的 [4+2] 环加成反应制备的。在补充途径中,化合物 5a-5q 也通过多组分反应获得,其产率与多步过程中获得的产率相似(25-84%),从 1a-1g、2 和 3a-3l 开始。