In the presence of cesium fluoride, the Claisen rearrangement of aryl propargyl ethers selectively provided 2-methylbenzofurans, which was successively treated with osmium tetroxide, periodic acid and 5% sodium hydroxide to give salicylaldehydes in good yields. The method was used to synthesize chelerythrine (2) via the common intermediate (8) prepared by the two routes as shown in Chart 3.
在
氟化铯存在下,芳基
丙炔醚的克莱森重排选择性地提供了
2-甲基苯并呋喃,依次用
四氧化锇、定期酸和 5%
氢氧化钠处理后得到
水杨醛,收率很高。如图 3 所示,该方法通过两种路线制备的共同中间体 (8) 合成了
白屈菜红碱 (2)。