Synthesis of aryl azides
A copper(II)-catalyzed conversion of organoboron compounds into the corresponding azide derivatives complements existing procedures for the preparation of aryl azides and will greatly facilitate copper- and ruthenium-catalyzed azide-alkyne cycloaddition reactions for the preparation of diversely functionalized 1-aryl- or 1-heteroaryl-1,2,3-triazoles derivatives.
K. D. Grimes, A. Gupte, C. C. Aldrich, Synthesis, 2010, 1441-1448.
Aromatic azides are formed in high yield from arenediazonium tosylates and sodium azide in water at room temperature. An in situ diazotization followed by azidation in the presence of p-TsOH allows the direct transformation of aromatic amines. Besides being experimentally simple, these methods do not require any metal catalysis and provide clean products without purification.
K. V. Kutonova, M. E. Trusova, P. S. Postnikov, V. D. Filimonov, J. Parello, Synthesis, 2013, 45, 2706-2710.
Reaction of [ArN2][BF4] salts immobilized in [BMIM][PF6] ionic liquid (IL) with TMSI and TMSN3 represents an efficient method for the preparation of iodo- and azido-derivatives via dediazoniation. Using TMSBr, competing fluorodediazoniation (ArF formation) and hydrodediazoniation (ArH formation) were observed depending on the substituents on the benzenediazonium cation.
A. Hubbard, T. Okazaki, K. K. Laali, J. Org. Chem., 2008, 73, 316-319.