Synthesis of a 4,5-epoxy-2-cyclohexen-1-one derivative via epoxide ring opening, 1,3-carbonyl transposition and epoxide ring regeneration: a synthetic study on a scyphostatin analogue
作者:Ryukichi Takagi、Kengo Tojo、Masato Iwata、Katsuo Ohkata
DOI:10.1039/b504039f
日期:——
A 6-alkyl-4,5-epoxy-6-hydroxy-2-cyclohexen-1-one derivative, a model compound for the hydrophilic moiety of scyphostatin, was stereoselectively synthesized from the Diels–Alder adduct. The key steps were the reductive cleavage of the 4,5-epoxide ring of the epoxidated adduct, the 1,3-carbonyl transposition of the 3-carbonyl group to the C1 position by a Wharton reaction and stereoselective bromination to provide a trans bromohydrin derivative, a precursor to the desired compound. Desilylation of the bromohydrin derivative with TBAF directly gave the target compound.
由 Diels-Alder 加合物立体选择性地合成了一种 6-烷基-4,5-环氧-6-羟基-2-环己烯-1-酮衍生物,该衍生物是鞘氨醇亲水性分子的模型化合物。关键步骤是还原裂解环氧化加合物的 4,5- 环氧环,通过 Wharton 反应将 3-羰基转位到 C1 位置,然后进行立体选择性溴化反应,得到反式溴化氢衍生物,即所需化合物的前体。用 TBAF 对溴海德林衍生物进行脱硅反应,直接得到目标化合物。