Effective Nitration of Anilides and Acrylamides by tert-Butyl Nitrite

Nitro compounds are important intermediates in synthetic organic chemistry and the chemical industry. Herein, the efficient copper-catalyzed [10% Cu(NO3)(2)3H(2)O] nitration of anilides was developed by using TBN (tert-butyl nitrite) as a nitrating reagent to give the corresponding nitro-substituted aromatic products in good to excellent yields. The use of TBN also led to the selective nitration of acrylamides at room temperature to afford only the (E) isomer of the nitration product. A series of anilides and acrylamides with a broad array of functional groups were well-tolerated by this procedure. This synthetic method has many advantages, which include inexpensive starting materials, mild reaction conditions, a fast reaction rate, and high yields. A mechanistic investigation indicates that a nitro radical, which is generated from the thermal homolysis of TBN, is involved in the two nitration processes.