金(I)催化進行分子內克來森類型重排反應合成含氮及含氧螺旋化合物

Abstract

含氮螺旋及含氧螺旋化合物不論是在天然物或是藥物方面均佔有非常重要的地位。本文探討利用金(I)催化含氮炔基之環己烯醇化合物，進行分子內克來森類型重排反應合成含氮螺旋化合物。 3-(溴甲基)環己-2-烯酮與4-甲基-N-(丙-2-炔)苯磺醯胺衍生物在鹼性條件下反應，得到含氮炔基支鏈的環己烯酮化合物。接著將環己烯炔酮化合物用硼氫化鈉還原成環己烯炔醇化合物，而得到環化起始物。 將含氮炔基之環己烯醇化合物利用金(I)陽離子催化進行分子內克來森類型重排反應得到一組含氮螺旋非鏡像異構物。透過X-ray繞射分析證明此一組非鏡像異構物之個別的相對立體結構。進一步將環化產物經由氫化反應、氧化反應可得到單一化合物。

Both azaspiro and oxaspiro units play important roles in natural products and medicine. In this thesis we report that gold(I)-catalyzed intramolecular Claisen-type rearrangement of starting material produced azaspiro compounds. Reaction of 3-(bromomethyl)cyclohex-2-enone and 4-methyl-N-(prop- -2-ynyl)benzenesulfonamide derivatives provided cyclohexenones bearing a propagyl aza-tether at C-3 under basic condition. The resulting enones were reduced to give the starting materials. Treatment of starting materials with a catalytic amount of Ph3PAuCl/ AgOTf produced a mixture of diastereomers. The relative stereochemistry of both isomers were confirmed by X-ray diffraction analysis. The mixture of diastereomers was reduced by H2 and a catalytic amount of Pd/C followed by oxidation of the resulting alcohol to ketone to give a single azaspiro compound. The stereochemistry of the saturated azaspiro compound was established by X-ray diffraction analysis.