| Summary: | 博士 === 國立中正大學 === 化學所 === 96 === There are three major subjects discussed in this thesis. The first part is the study of synthesis and catalytic reactivity of nitrogen donor ligand ligated Pd(II) complexes and Cu(I) NHC complexes supported on gold nanoparticles surfaces. The gold nanoparticles with core diameter of 3.9-4.7 nm were stabilized with a mixture of octanethiolates and dipyridylphosphinicamido undecanethiolates. Without varying the size of central Au cores, palladium complexes and ionic liquids, [HS-hmim][PF6] and [HS-hmim][HSO4], were immobilized onto these Au nanoparticles through chelation to the surface bound bidentate pyridyl. Hybrid catalysts of this type were dissolvable and precipitable, and their structures and reactions were investigated by solution nuclear magnetic resonance (NMR) spectroscopy with a resolution typically attained for soluble systems. These surface-bound Pd(II) complexes were highly effective catalysts for [2+2+2] alkyne cyclotrimerization reactions to give highly congested benzene rings with fairly good selectivity. The catalytic reactivity of these interphase catalysts was even higher than that of their unbound counterparts. In addition, they can be easily separated and quantitatively recovered by simple filtration. The recovered catalysts can be effectively recycled many times and their electron microscopy images and NMR spectra showed negligible difference from those of freshly prepared. The complete transformation by Au-bound Pd(II) catalyst with a loading of 4 mol% can be achieved within one hour for most alkynes. The same catalysis can be further accelerated in ionic liquid under microwave conditions to give nearly 100% of cyclotrimerized products in minutes.
Room temperature ionic liquid [HS-hmim][PF6] and [HS-hmim][HSO4] were prepared to be immobilized onto the surface of Au nanopartocles. These surface-bound ionic compounds RS-Au-S-hmim[PF6] and RS-Au-S-hmim[HSO4] were found to be highly effective catalysts for various organic transformations such as Biginelli、Pechmann condensation and aldehyde cyclotrimerization reactions. These Au colloidal-immobilized ionic compound catalysts can be effectively recycled many times in cases of aldehyde cyclotrimerization reactions.
In the second part of the thesis, we have also studied the synthesis of a series of C3v pyridyl ligands supported Cu(I) complexes, Cu(L)(sol)PF6, where L = O=P(2-py)3 and O=P[O(CH2)2-py]3. These Cu(I) complexes
were proved to be effective catalysts for a variety of organic reactions such as Sonagashira, C-S bond coupling and allylic oxidation reactions. The same catalyses can also be further accelerated under microwave conditions to give nearly 100% of products in minutes.
The last part of this thesis was to study the coordination chemistry between tripodal nitrogen donor ligands O=P(2-py)3 and O=P[O(CH2)n-py]3 (n = 0, 1, 2) with a range of silver (I) salts, AgX, where X = BF4-、ClO4-、SO3CF3- and PF6-). We have found some counter anion-influenced crystal growth which may be the result of size difference. We used 1H and 31P NMR spectroscopy as well as X-ray crystallographic analysis to study their solution and solid structures.
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