title: Theoretical studies on the tautomerism of 1,5,6,7-tetrahydro-4H-indazol-4-ones.
abstract: Computational studies on three tautomeric forms of four 1,5,6,7-tetrahydro- 4H-indazol-4-one derivatives: 1,5,6,7-tetrahydro-4H-indazol-4-one (1), 6,6-dimethyl- 1,5,6,7-tetrahydro-4H-indazol-4-one (2), 3-methyl-1,5,6,7-tetrahydro-4H-indazol-4-one (3) and 3,6,6-trimethyl-1,5,6,7-tetrahydro-4H-indazol-4-one (4), have been performed at different levels, ranging from semiempirical AM1, ab initio Hartree-Fock HF/6-31G* and HF/6-31G** to B3LYP/6-31G** density functional calculations. These calculations have been used to establish the most stable tautomer, which in all cases was in agreement with the experimental data.
authors.affiliation: Departamento de Química Orgánica y Bio-Orgánica, Facultad de Ciencias, UNED Senda del Rey 9, E-28040 Madrid, Spain. cperez@bec.uned.es
authors.forename: Carlos Pérez
authors.initials: CP
authors.lastname: Medina
authors.forename: Concepción
authors.initials: C
authors.lastname: López
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Claramunt
mesh_terms: D003198:Computer Simulation; D007191:Indazoles / Q000737:chemistry*; D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008958:Models, Molecular
chemical_list: D007191:Indazoles