| Summary: | 碩士 === 國立中央大學 === 化學系 === 84 === 1. 二苯氯甲烷之硼氫化鈉還原反應研究 硼氫化鈉與有機
鹵化物在80%二(2-甲氧乙)醚水溶液中反應,結果發現硼氫化鈉 不能完全
捕捉溶離反應的正離碳子,不但有還原產物還有醇類的產生.利用氣相層析
作產物分析,結果顯示隨著芳香環上取代基由給電子到拉電子基的不同,還
原產物與 醇類的比值呈現愈來愈小的趨勢,以及鹵化物活性大的還原產
物百分比也會增大. 2. 二苯甲酮系列氧-17核磁共振化學移差的研究
利用氧-17核磁共振來探討二苯甲酮系列化合物中,芳環上取代基電子效應
及苯環 上多了三個甲基的立體效應對羰基氧的化學移差影響,結果顯示
隨著芳環上拉電子基 愈強,遮蔽效應愈小,則會在較低磁場吸收而立體效
應的影響則更大;並尋求與自由能 線性關係參數(Linear Free Energy
Relationship Parameters)的相關情形.
1. Research on the Benzhydryl Chloride Reducing Reaction of
Sodium Borohydride Sodium borohydride with organic halo-
compound is concluded in aqueous solution of 80%(v/v) diglyme.
It is found that Sodium Borohydride cannot completely trap
carbocation produced in solvolysis. In addition, reduced
products and alcohols are also comfirmed by employing gas
chromatography(GC) analyst. When the substituent bonded to the
aromatic ring shifts from electronic donating group toword
electronic withdrawing group, the reduced produced products/
alcohol ratio tends to be smaller. 2. Research on the Substition
Chemical Shift(SCS) of Oxygen-17 Nuclear Magnetic Resonance(
NMR) of Benzophenone Series Oxygen-17 NMR is utilized to
study the influence of the electronic effect for the
substituent bonded to the aromatic ring and the steric effect of
three more methyl group which bonded to the aromatic ring on the
chemical shift of oxygen in the carbonyl in the benzophenone
series compound. As a result, the shielding effect is lessened
if the electron withdrawing capability of the substituent which
bonded to aromatic ring is enhanced and down-field absorption
will occur. Similarly, stronger steric effect duing to the
2'4'6'-trimethyl groups leads to down-field absorption.
Besides, the relationship between Linear Free Energy
Relationship(LFER) parameters and steric effect/electron
withdrawing capability is investigated.
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