chemistry. The formal cycloaddition of bicyclobutanes (BCBs) with two- or three-atom partners has recently been extensively explored for the construction of bicyclohexanes and bicycloheptanes, but applications to the synthesis of medium-sized bridged carbocycles remained more limited. We report herein the formal [4+2] cycloaddition of BCB ketones with silyl dienol ethers. The reaction occurred in the presence
含有高比例 Csp 3的双环碳环已成为极具吸引力的合成目标,因为它们在药物
化学中具有多种应用。双
环丁烷(BCB)与两个或三个原子伙伴的正式环加成最近被广泛探索用于构建双
环己烷和双
环庚烷,但在合成中等尺寸桥接碳环的应用仍然较为有限。我们在此报告了 BCB 酮与甲
硅烷基二烯醇醚的正式[4+2]环加成反应。该反应在 5 mol%
三氟甲磺酸铝作为
路易斯酸催化剂的存在下发生。通过烯醇醚中间体的酸性
水解,可以以高达定量的产率获得刚性双环[4.1.1]
辛烷(BCO)二酮。该过程允许 BCB 底物和二烯上存在一系列芳香族和脂肪族取代基。所得BCO产物可以通过还原和交叉偶联反应进行功能化。