THEORETICAL STUDY OF THE MECHANISM OF FORMATION OF 4-AMINOISOXAZOLES. 2. AN UNUSUAL REARRANGEMENT OF OXIMINONITRILES
Keywords:aminoisoxazoles, aminooxazoles, lithium complexes, anion rearrangement, density functional method
The base-catalyzed cyclization of oximinonitriles in the presence of lithium ions leads to 4-aminoisoxazoles and, sometimes, to 5-aminooxazoles. Modeling using the density functional theory and the HF and MP2 methods indicated that both 4-aminoisoxazoles and 5-aminooxazoles are formed from the anion of one of the oximinonitrile lithium complexes. The formation of 5-aminooxazoles proceeds through an unusual anion rearrangement. The thermodynamic parameters of the transition states were calculated to explain the predominant formation of 4-aminoisoxazoles.
Authors: V. P. Kislyi, E. B. Danilova, and V. N. Solkan.
English Translation in Chemistry of Heterocyclic Compounds, 2013, 49 (7), pp 1042-1054