Tetrakis(pyridin-2-yloxy)silane [Si(OPy)4] is easily prepared by trans-silylation between silicon tetrachloride and trimethyl(pyridin-2-yloxy)silane in the molar ratio of 1:4. This novel reagent is effectively employed as a mild dehydrating reagent in forming various carboxamides from the corresponding carboxylic acids and amines that involve secondary or tertiary alkyl substituted ones in good to high yields without using any basic promoters such as tertiary amines or 4-(dimethylamino)pyridine.
                                    四(
吡啶-2-氧基)
硅烷[Si(OPy)4]可通过
硅四
氯化物与三甲基(
吡啶-2-氧基)
硅烷在1:4的摩尔比下通过反式
硅基化轻松制备。这种新型试剂有效地用作温和脱
水剂,在无需使用叔胺或4-(二甲基
氨基)
吡啶等碱性
促进剂的情况下,以良好至高产率形成各种羧酰胺,涉及含有二级或三级烷基取代的相应
羧酸和胺。