Stereocontrolled Construction of Tricyclic Furan and Pyrrolyl Derivatives via Tungsten-Mediated [3+2] Cycloaddition and Intramolecular Diels-Alder Reaction
作者:Rai-Shung Liu、Wen-Li Lin、B. Pratap Taduri
DOI:10.1055/s-2002-35230
日期:——
Vinylpropargyl tungsten complexes were prepared to comprise a tethered unsaturated ester designed for intramolecular Diels-Alder reaction. Treatment of these vinylpropargyl tungsten complexes with aldehydes and imines in the presences of BF 3 .OEt 2 resulted in a [3+2] cycloaddition to give 2,5-tlihydrofuran and pyrrole derivatives. Hydrodemetalation of these tungsten heterocyclic compounds was achieved
制备乙烯基炔丙基钨配合物以包含设计用于分子内 Diels-Alder 反应的束缚不饱和酯。在BF 3 .OEt 2 存在下用醛和亚胺处理这些乙烯基炔丙基钨配合物导致[3+2]环加成,得到2,5-三氢呋喃和吡咯衍生物。这些钨杂环化合物的加氢脱金属是在 CH 3 CN 中用 Me 3 NO 实现的,得到的呋喃基和二氢吡咯基二烯经历高度非对映选择性的分子内 Diels-Alder 反应,有效地得到三环呋喃和吡咯基衍生物。该方法提供了三环呋喃和吡咯衍生物的短立体选择性合成。