Improved amide synthesis using silver as a catalyst
The Madix and Friend laboratories have developed a novel amide synthesis that uses metallic silver or silver-based alloy with oxygen adsorbed on the surface to catalyze the reaction of primary or secondary amines with alcohols or aldehydes. The catalyst may be supported on another solid and may be promoted with additives if desired; it can also be used in the pure, unsupported state. One of the main advantages of this synthesis is that the starting materials are not only inexpensive and widely-available, but they are also safe to handle and produce environmentally friendly byproducts (under optimal conditions, only water). Furthermore, this reaction provides for heterogeneous catalysis, and takes place under mild reaction conditions (at or near room temperature and atmospheric pressure). The synthesis is highly selective and yields the desired product in one step, and the byproducts are easily separated out.
Intellectual Property Status: Patent(s) Pending
The amide group is a key structural component of natural products, polymers, pharmaceuticals, and other synthesized compounds. Amidation reactions are therefore a crucial synthetic tool. However, current processes for introducing the amide group, such as reactions of carboxylic acid derivatives, modified Staudinger reactions, halide aminocarbonylation, ketoxime and aldoxime rearrangements, and transition-metal-catalyzed aminocarbonylation of alkenes and alkynes, are often procedurally complex, frequently involve costly or hazardous reagents, and may produce toxic chemical waste. Additionally, they usually require harsh reaction conditions such as high temperatures and high pressure.