臺灣博碩士論文加值系統

一、利用鑭系化合物促進烯酮和醛的醛醇縮合反應:對於非環狀的a,b-不
飽和羰基系統而言，1,2-及1,4-加成反應是很好的形成碳-碳鍵模式。但
是相較之下，想要在烯酮的飽和a碳上進行醛醇縮合反應是相當有問題的
。最近的研究大多數著眼於不飽和a碳的烷化反應(a-alkylation)，只有
少數的研究報告是關於非環狀烯酮的飽和a碳烷化反應(a'-alkylation)。
文中首次利用鑭系化合物來輔助甲基乙烯酮和醛類進行a'-alkylation，
這種模式可以很有效地製備一些在合成上相當重要的羥基烯酮化合物。二
、Enterocin的合成研究:本文是對一種很有效的抗生素－enterocin的合
成研究，它是從Streptomyces candidus所提煉而得，其主要的架構為具
有三個羥基的[ 3. 2. 1 ]雙環辛烷，本研究可以經由McMurry偶合反應的
方式來製備此基本骨架。

PART I. LANTHANIDE (III) PROMOTED ALDOL CONDENSATION OF ENONES
AND ALDEHYDES.1,2 - and 1,4 - additions to acyclic a,b-
unsaturated carbonyl systems are wellprecedented carbon-carbon
bond forming reactions. In contrast , the aldol con-densation at
the saturated a-carbon of enones ( a'-alkylation ) is quite
pro-blematic. A number of recent studies have focused on the
alkylation of the sp2a-carbon ( a-alkylation ), but very little
worked has been carried out on a'-alkylations of acyclic enones.
The first lanthanide (III) mediated a'-alkyla-tion of MVK
withaldehydes is described in this thesis. This methodology
allowsthe efficient preparation of a number of synthetically
important hydroxyenonesPART II. SYNTHETIC STUDIES OF THE
ENTEROCIN. The synthetic study toward to thetotal synthesis of
enterocin , a potent antibiotic from Streptomyces candidus,is
described in this thesis. A trihydroxybicyclo[3.2.1]octane , the
basic ske-leton ofenterocin, was prepared via the McMurry
coupling method.