Department of Chemistry, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, USA.
J Am Chem Soc. 2011 Sep 14;133(36):14248-51. doi: 10.1021/ja2066169. Epub 2011 Aug 18.
The Mukaiyama cross-aldol reaction of α-fluoro-, α-chloro-, and α-bromoacetaldehyde-derived (Z)-tris(trimethylsilyl)silyl enol ethers is described, furnishing anti-β-siloxy-α-haloaldehydes. A highly diastereoselective, one-pot, sequential double-aldol process is developed, affording novel β,δ-bissiloxy-α,γ-bishaloaldehydes. Reactions are catalyzed by C(6)F(5)CHTf(2) and C(6)F(5)CTf(2)AlMe(2) (0.5-1.5 mol %) and provide access to halogenated polyketide fragments.
描述了α-氟代、α-氯代和α-溴代乙醛衍生的(Z)-三(三甲基硅基)甲硅烷基烯醇醚的 Mukaiyama 交叉-羟醛反应,生成反式-β-硅氧基-α-卤代醛。开发了一种高度非对映选择性的一锅法顺序双羟醛缩合反应,得到了新型的β,δ-双硅氧基-α,γ-双卤代醛。反应由 C(6)F(5)CHTf(2)和 C(6)F(5)CTf(2)AlMe(2)(0.5-1.5mol%)催化,可用于合成卤代聚酮片段。