TAUTOMERISM IN NITROTRIAZOLES - STRUCTURE INVESTIGATION BY COMBINED H-1, C-13 AND N-15 NMR-SPECTROSCOPY

The tautomerism and isomerism of triazoles make the structure analysis of such compounds a difficult problem, and in the case of several nit rotriazoles a detailed structure assignment had been lacking up to now . Supported by selected compounds, a definite structure determination of ten nitrotriazoles was achieved by combined application of N-15 NMR spectroscopy and increment calculations. This method also succeeded i n cases where equilibria of tautomers were present. An evaluation of t he shift data and coupling modes gave systematic references to structu re and substituent influences. (C) 1998 John Wiley & Sons, Ltd.