Structure and Reactivity of Indazoles

Photophysical experiments and theoretical calculations have been used to determine the tautomeric equilibrium between IH- and 2/f-indazoles (15a) and (15b) both in the ground (So) and in the excited state (S,) 94JPC10606 . The measurement of sublimation and solution enthalpies in water at 25°C, basicities in the excited state of 1-methylindazole (pAa = 1.61) and 2-methylindazole (pA a = 3.00), and MP2//6-31G //6-31G calculations of the difference in energy between their conjugated acids in the ground state allows the complete thermodynamic cycle to be established. Indazole in the excited state is 3.0 pA a units more acid (pA a = 1108) and 1.8 pK units more basic 

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Structure and reactivity of neutral pyrazole, its anion and its cation. 2.2 Structure and reactivity of substituted pyrazoles. 2.3 Structure and reactivity of indazoles. 2.4 Dipole moments Structural Methods. 3.1 X-Ray diffraction. 3.2 Microwave spectroscopy. 3.3 H NMR spectroscopy. 3.4 C NMR spectroscopy. 3.5 Nitrogen NMR spectroscopy 3.6 UV spectroscopy. 3.7 JR spectroscopy. 3.8 Mass spectrometry. 3.9 Photoelectron spectroscopy. 3.10 Electron spin resonance spectroscopy Thermodynamic Aspects. 4.1 Intermolecular forces. 4.2 Stability and stabilization. 4.3 Conformation and configuration Tautomerism... 

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