有機金屬釕、鉑、金應用於烯炔類分子進行分子內環化反應

Ruthenium、Platinum and Gold Catalyzed Intramolecular Cyclization of Enynes

林銘源(Ming-Yuan Lin)

指導教授 ： 劉瑞雄

國立清華大學/理學院/化學系/博士(2007年)

https://doi.org/10.6843/NTHU.2007.00072

摘要

本論文共分五個章節，主要是利用過渡金屬催化非環狀的烯炔類分子進行環化反應。
第一章是以釕金屬錯合物TpRuPPh3(CH3CN)2PF6當催化劑成功地對炔類與環氧丙烷進行環化反應，經由環氧丙烷上的取代基及骨架提供了一個有效的方法可以選擇性地分別合成2-萘酚、2-茚酮衍生物、1-H-茚衍生物或環己雙烯酮衍生物。而且經由捕捉實驗及同位素標定實驗，我們合理地推測此反應包含釕金屬-π-烯酮中間體，有關於環氧丙烷上的不同取代基之研究仍然持續進行中。
第二章是以釕金屬錯合物TpRuPPh3(CH3CN)2PF6當催化劑催化碘炔類與環氧丙烷進行環化反應，發現此反應有很好的溶劑取決化學選擇性。在以二甲基甲醯胺為溶劑時可以選擇性地得到1-碘-2-萘酚衍生物而在以苯為溶劑時則反應傾向生成碘取代的七員環醚類衍生物。在二甲基甲醯胺和苯為溶劑的反應中間體分別為釕金屬-碘取代亞乙烯基錯合物和釕金屬-π- 碘化炔錯合物。而由於碘取代的電子效應導致環氧丙烷上氧原子進行分子內攻擊時偏向7-endo-dig這種不尋常的環化反應。
第三章是以二氯化鉑為催化劑可以成功並有效率地催化雙烯丙炔醇的環化異構化成苯乙烯衍生物。此催化反應可以容忍異原子，或非環狀系統 ; 我們也發現在此反應中的1,3-亞烷基轉移，並以同位素碳十三原子的標定實驗清楚地證明1,3-亞烷基轉移反應路徑。有關於此反應應用於更複雜的分子之研究仍然持續進行中。
第四章是以二氯化鉑為催化劑，催化具有五員環結構的雙烯丙炔醇環化異構化成環丙烷。此催化反應可以容忍硫與氧等異原子，然而當環外烯上有五員環取代時也可得到具有螺旋雙環型態的環丙烷。在有機合成上我們也可以利用此方法合成許多天然物的前驅物。
第五章是以氯化金催化雙烯與拉電子丙炔醇的環化異構化反應。此催化反應可以容忍酯與酮二種拉電子取代基，然而當拉電子基換成醯胺時，則反應則無法進行。而經由同位素標定實驗我們也提出合理的反應機構去闡述反應的進行模式。有關於此催化反應的應用仍然持續進行中。

關鍵字

釕 ； 鉑 ； 金 ； 烯炔

並列摘要

The first chapter describes TpRu(PPh3)(CH3CN)2PF6 catalyzed cyclization of epoxide-alkyne. The reaction products are highly dependent on the substituent and structural skeleton of the epoxide substrates. We propose a plausible mechanism involving ketene-alkene intermediates, generated from an oxygen migration from epoxide to terminal alkyne. This proposed mechanism is supported by trapping experiments using isobutyl alcohol as well as deuterium labeling experiment. Examination of this reaction on molecules bearing various alkyne-epoxide functionalities is under investigation.
The second chapter discusses TpRu(PPh3)(CH3CN) 2PF6 catalyzed cyclization of 1-(2’-iodoethynylphenyl)- 2-alkyloxiranes gave 1-iodonaphthan-2-ol derivatives in DMF very efficiently, but preferably yielded 6-iodo-7-oxa-benzocycloheptene in benzene. The active intermediates in DMF and benzene were ruthenium-2-iodovinylidene and π-iodoalkyne species respectively. The intramolecular attack of epoxide at the π-iodoalkyne intermediate preferably proceeds via a 7-endo-dig cyclization, and this unusual pathway is attributed to the electronic effect of an iodo substituent.
The third chapter describes PtCl2 catalyzed cycloisomerization of cis-4,6-dien-1-yn-3-ols with an unusual skeletal rearrangement; this catalytic reaction is applicable to a wide range of substrates. Its 1,3-alkylidene migration pathway is clearly established by isotope-labeled experimental evidences. Application of this new catalysis of complex molecule is under current investigation.
The fourth chapter describes PtCl2/CO catalyzed cycloisomerization of (cyclopent-1-enyl)prop-2-yn-1-ol to cyclopropane derivatives. This catalytic reaction is applicable to substrates that contain heteratom compounds. Further application of our synthetic method for the synthesis of naturally occurring compounds is under current investigation.
The last chapter describes AuCl catalyzed cycloisomerization of alkene and electron-withdrawing alkyne. These new gold-catalyzed reaction is applicable to ketone and ester substituents. Its mechanism is clearly established by isotope-labeled experimental evidences. Application of this new catalysis of complex molecule is under current investigation.

並列關鍵字

Ruthenium ； Platinum ； Gold ； Enynes

參考文獻

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3. For example of migration of a alkylthio group, see: David C. Miller, Robert J. Angelici. Organometallics.1991, 10, 79.