3,6,6-TRIMETHYL-4-OXO-1-(2-PYRIDYL)-4,5,6,7-TETRAHYDROINDAZOLE IN SCHMIDT REACTION AND BECKMANN REARRANGEMENT CONDITIONS FOR THE 4-HYDROXYIMINO DERIVATIVE

Abstract

Treatment of 3,6,6-trimethyl-4-oxo-1-(2-pyridyl)-4,5,6,7-tetrahydroindazole with sodium azide in acids gives 3,7,7-trimethyl-5-oxo-1-(2-pyridyl)-5,6,7,8-tetrahydro(4H)pyrazolo[4,3-b]azepine. Heating 1-(2-pyridyl)-3,6,6-trimethyl- and 1-phenyl-6,6-dimethyl-4-hydroxyimino-4,5,6,7-tetrahydroindazoles in polyphosphoric acid gives 1-phenyl-5,6-dimethyl- and 1-(2-pyridyl)-3,5,6-trimethyl-4-aminoindazole respectively. The reactions of the latter with 4-dimethylaminobenzaldehyde gave the 4-(4-dimethylaminobenzalamino) derivative and with 2-formyldimedone the 4-(4,4-dimethyl-2,6-dioxocyclohexylidenemethylamino) derivative.

Authors: L. G. Delyatitskaya, M. V. Petrova, S. Grinberga, N. N Tonkikh, and A. Ya. Strakov.

English Translation in Chemistry of Heterocyclic Compounds, 2000, 36 (6), pp 728-732

http://link.springer.com/article/10.1007/BF02297683