Departamento de Química Orgánica (Módulo 01), Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
Chemistry. 2011 Jan 24;17(4):1283-93. doi: 10.1002/chem.201002637. Epub 2010 Dec 10.
Good to excellent stereoselectivities were achieved in the reductive cyclization (with Et(3)SiH/trimethylsilyl trifluoromethanesulfonate (TMSOTf)) of enantiopure hydroxy sulfinyl ketones en route to 2,5-cis-disubstituted tetrahydrofuran skeletons. Electrostatic effects of the exocyclic sulfoxide, which stabilized the reactive intermediate oxocarbenium conformations, were responsible for the observed stereocontrol. A model is proposed to explain the results. The use of this reaction and the asymmetric β-ketosulfoxide reduction as key steps facilitated the total enantioselective synthesis of the natural β-C-aryl glycoside (+)-goniothalesdiol.
在手性羟基亚砜酮的还原环化（采用 Et(3)SiH/三甲基硅基三氟甲磺酸酯 (TMSOTf)）反应中，获得了极好的立体选择性，这是通向 2,5-顺式二取代四氢呋喃骨架的关键步骤。非环亚砜的静电效应稳定了反应性中间体氧杂碳正离子构象，这是观察到的立体控制的原因。提出了一个模型来解释结果。该反应和不对称β-酮亚砜还原的使用作为关键步骤，促进了天然β-C-芳基糖苷(+)-goniothalesdiol 的全对映选择性合成。
