Both Henry reaction and Curtius rearrangement are interesting alternatives to reductive amination or reduction of oxime used for the introduction of the nitrogen atom. As already mentioned, all of these proposed routes avoid expensive catalysts and commence from inexpensive starting materials, readily available in large quantities (e.g., ethylamine at 0.018 $/g, 2-bromoethyl acetate at 0.22 $/g, 5-chloro-2-pentanone at 0.08 $/g, or ethanolamine at 0.012 $/g). Only few of these substrates were used in the previously published/patented syntheses. In Figure , their prices are indicated in red font. Substrates and their prices (the lowest ones we were able to identify) scaled to $/g are colored in red.