Reactions of Bis(oxy)enamines with O-Nucleophiles in the Presence of Metal Salts
NO donors are an emerging class of pharmaceutical compounds, with many important functions in the cardiovascular, nervous and immune systems. With great therapeutic potential, the development of new NO donor compounds would be of great medicinal value, potentially opening a whole class of drugs to be used to treat various ailments. This project studies a specific class of compounds, substituted cyclic oxime ethers, which have proven to be useful intermediates in fields such as medicine and biochemistry. The cyclic structure along with a determinable substitutable group at the C3 position is highly valuable, as it allows the oxime ether to act as a convenient precursor for a variety of useful products, playing key components in many drugs. And with a substituted nitrate group, which is an O-nucleophile, the oxime ether has the potential to become an NO-donor, and hence become a possible intermediate in a wide array of NO donor drugs. Co(NO)3 was used in the synthesis of the cyclic oxime ether, directly from a phenyl substituted bis(oxy)enamine intermediate, producing an entirely new compound: α-hydroxyoxime nitrates, the oxime ether being substituted with a nitrate group. This new reaction of the synthesis of α-hydroxyoxime nitrates was further studied for optimization purposes, in order to open a new class of NO donor precursors. In addition, other nucleophiles were also explored in this class of reactions, forming important bonds such as C-N and C-S bonds, with key structures for other types of synthesis intermediates and precursors. Different metal nitrates, or various other nucleophiles in place of the nitrates, were used in reaction with bis(oxy)enamine, and the yield and structure of the final products were determined by NMR spectra. Successful optimization of the synthesis of α-hydroxyoxime nitrates has been achieved, where the conditions for optimum synthesis involve using Cr(NO3)3•9H2O which achieved a high yield of 76%, dissolved in THF with the bis(oxy)enamine starting compound. It has been determined that the metal in the salt affects the reaction pathway, as the nature of the metal cation affects its efficiency to cleave the N-O bond in the starting compound (with d-block elements being the best performing), and H+ ions can promote the reaction as well. Also, the reaction proceeds with different types of bis(oxy)enamines, meaning the substrate scope can be expanded to give a variety of products. The reaction can also proceed to form other products with different nucleophiles other than the nitrate group, where the C-N and C-S bonds were successfully formed in the reactions from bis(oxy)enamine to oxime ether. Thus, this class of reaction in converting the bis(oxy)enamine to a cyclic oxime ether has potentially opened a new class of NO donor compounds, and further possesses the potential to form a wide variety of products to be used in other important synthesis procedures.
告訴你「拉午耳」 「亨利」的壓力有多大 ─自製簡易的 IC 電路板來討論拉?
This research is aimed to make an in-depth exploration into Raoul’s Law and Henry’s Law by using an accurate but simple vapor pressure gauge. The gauge is constructed from non-complicated electronics components- electronics IC PCB, film resistor, digital multi-meter, and battery. In the first step, we measured the vapor pressure of six kinds of liquids and 3 liquid mixtures- water, ethanol, chloroform, acetone, benzene, toluene, mixture of water and ethanol, mixture of chloroform and acetone, mixture benzene and toluene. From the results of this experiments, the vapor pressures of water and ethanol liquid mixture, and chloroform and acetone liquid mixture were slightly lower than their theoretic values-called negative deviation solution, while the vapor pressure of the benzene and toluene liquid mixture was quite close to its theoretic value-near an ideal solution. In the second step, the individual vapor pressures of water, ethanol, and chloroform were measured at various temperatures; the vapor heat(ΔH) were calculated by using the lausius-Clapeyron equation. In the final step, we used the gauge and other non-commercial instruments to measure the B.O.D. values of water from the Kaohsiung Love River, found the P-T correlation using Gay-Lussac’s Law, and calculated the absolute zero temperature value by extrapolation. 本研究是利用一些簡易的電子元件－電路IC板、電阻膜、數位三用電表和電瓶來組裝一 個準確、簡易的氣壓量測器。我們將此量測器用來深入探討「拉午耳定律」及「亨利定律」 。 首先，我們測量了水、乙醇、氯仿、丙酮、苯、甲苯等六種純液體的蒸氣壓，並測量了(水＋乙醇)、(氯仿＋丙酮)、(苯＋甲苯)等兩成份系溶液的混合蒸氣壓。結果發現(水＋乙醇) 、(氯仿＋丙酮)的混合蒸氣壓都比理論值低了一些，此稱為負偏差溶液；(苯＋甲苯)的混合蒸氣壓與理論值差不多，較接近理想溶液。 接下來，我們還測量了不同溫度下水、酒精及丙酮的蒸氣壓，並利用clausius－clapeyron equation求出液體純質的汽化熱( H Δ )。 最後，我們還搭配了自製的儀器裝置，來測定愛河水質的B.O.D.值(生化需氧量)以及探討氣體的給呂薩克定律(P~T關係)，並利用外差法來推求絕對零度。