Inside Cover: Sustainable Synthesis of Balsalazide and Sulfasalazine Based on Diazotization with Low Concentrations of Nitrogen Dioxide in Air (Chem. Eur. J. 17/2017)

From waste to valuables: The industrial production of copper nitrate from copper produces large amounts of toxic NO2. Instead of costly denitrification, this process has now been used for the diazotization of anilines and subsequent synthesis of valuable azo compounds. A wet scrubber plays a key role in this strategy. The studies demonstrate that diazonium salts, obtained from the scrubber in up to quantitative yields, can directly be employed in azo coupling reactions thus opening an attractive access to the industrially important group of azo compounds. More information can be found in the Communication by M. R. Heinrich, et al. on page 4042 ff.