The practical utility of decarboxylative transformations in organic synthesis is discussed, and the decarboxylative deuteration of (hetero)aromatic carboxylic acids is disclosed as a further example. Various monodeuterated arenes were synthesized under mild conditions, in a single step from easily accessible aromatic carboxylic acids and deuterium oxide. Copper catalysts were found to have the widest scope, but silver catalysts are superior for some ortho-substituted benzoates. A few substrates, e.g. quinoline-2-carboxylic acid, decarboxylate even in the absence of a metal catalyst.
讨论了脱羧转化在有机合成中的实际应用,并披露了作为进一步例证的(杂)芳香
羧酸的脱羧
氘化反应。在温和条件下,通过一步反应,从易于获得的芳香
羧酸和
氘水合成了多种单
氘代
芳烃。
铜催化剂具有最广泛的适用范围,但对于某些邻位取代的
苯甲酸盐,
银催化剂表现更优。少数底物,例如
喹啉-2-
羧酸,即使在无
金属催化剂的情况下也能发生脱羧反应。