Fundamental study for development of novel catalytic reactions by transitionmetal complexes involving carbon-oxygen bond cleavage or formation steps

我们研究了钯配合物对有机化合物碳氧键的活化及其在新型催化过程中的应用，主要发现：（A）研究了在新戊酸酐存在下钯配合物直接加氢羧酸制醛的反应条件的改进。在极性溶剂如丙酮和DMF中，氢化反应进行得更快。钯-叔膦催化剂的性质也对加氢反应有影响，当使用乙酸钯和5当量的三（对甲苯基）膦催化剂时，醛的产率最高。非均相催化剂如钯炭也催化该氢化反应。(B)用含两个叔膦的零价钯-苯乙烯配合物裂解乙烯酮二聚体的碳-氧键，得到相应的钯内酯配合物。通过X-射线晶体学和NMR光谱学完全确定了palladalactone复合物的结构。还研究了钯内酯络合物的化学反应性。(C)研究了钯配合物催化胺的氧化羰基化反应。以1，4-二氯-2-丁烯为氧化剂，以较好的收率合成了草酰胺.

We have studied the carbon-oxygen bond activation of organic compounds by palladium complexes and its application to novel catalytic processes.Major findings : (A) improvement of the reaction conditions of the diect hydrogenation of carboxylic acids to aldehydes by palladium complexes in the presence of pivalic anhydride was investigated. The hydrogenation reaction proceeded faster in polar solvents such as acetone and DMF. The nature of palladium-tertiary phosphine catalyst also affected the hydrogenation, the highest yield of aldehyde was obtained with use of palladium acetate and five equivalents of tri (p-tolyl) phosphine catalyst. The heterogeneous catalysts such as palladium on charcoal also catalyzed this hydrogenation reaction.(B) carbon-oxygen bond of ketene dimer was cleaved by a zerovalent palladium-styrene complex having two tertiary phosphines to give corresponding palladalactone complex. The structure of the palladalactone complex was fully determined by X-ray crystallography and NMR spectroscopy. Study of the chemical reactivity of the palladalactone complex was also investigated.(C) study on the oxidative carbonylation of amines catalyzed by palladium complexes was investigated. Oxamide was obtained in a good yield by using 1,4-dichloro-2-butene as an oxidizing agent.