Development of novel double- and single carbonylation processes catalyzed by organotransition metal complexes

本文研究了钯配合物催化胺和醇的羰基化反应和钯配合物活化C-O键及其在新型催化加氢反应中的应用，主要发现：（a）在水相体系中，钯配合物与碘化氢促进剂催化苯甲醇直接羰基化合成苯乙酸的新方法。将羰基化方法应用于其他芳基甲醇类似物，提供了制备3-异色满酮、1，4-苯乙酸、2-羟基苯乙酸和2-萘乙酸的方便方法。（B）对（苯乙酰基）钯配合物与仲胺和仲醇的反应的研究为产生酰胺和酯的不同类型机理的操作提供了支持证据。酰胺的形成建议进行通过配位的胺的钯中心，然后由其亲核攻击的酰基上的碱援助。另一方面，在碱存在下酰基钯与醇反应中酯的形成与通过中间体酰基-醇盐络合物进行的反应机理是相容的。（c）钯（O）络合物活化各种含氧有机化合物如羧酸酐、羧酸酯和双乙烯酮中的C-O键，发现导致相应的C-O键断裂产物。基于这些发现，实现了在钯络合物催化的新戊酸酐的存在下，通过酸酐的氢化或羧酸的直接氢化来制备无卤醛的方法。

We investigated here (I) the carbonylation processes of amitnes and alcohols catalyzed by palladium complexes and (2) C-O bond activation by palladium complexes and its application to novel catalytic hydrogenation processes.Major findings : (a) New direct carbonylation of benzyl alcohol catalyzed by a palladium complex with hydrogen iodide promoter to give phenylacetic acid in excellent yields in aqueous systems was discovered. Application of the carbonylation processes to other arylmethanol analogues provided convenient means to prepare 3-isochromanone, 1, 4-benzeneacetic acid, 2-hydroxybenzeneacetic acid, and 2-naphthaleneacetic acid.(b)Examination of the reactions of the (phenylacetyl)palladium complexes with secondary amines and alcohols provided supporting evidence for operation of different types of mechanisms for yielding amides and esters. The amide formation is proposed to proceed through coordination of the amine to the palladium center followed by its nucleophilic attack on the acyl group aided by a base. On the other hand, the formation of esters in reaction of acylpalladium with alcohols in the presence of a base is compatible with the reaction mechanism proceeding through an intermediate acyl-alkoxide complex.(c)Activation of C-O bonds in various oxygen-containing organic compounds such as carboxylic acid anhydrides, carboxylic esters, and diketene by palladium(O) complexes was found to lead to the corresponding products with C-O bond cleavage. Based on these findings, realization of halide-free aldehyde preparation processes by hydrogenation of anhydrides or direct hydrogenation of carboxylic acids in the presence of pivalic anhydride catalyzed by palladium complexes was achieved.