5-DIAZO-6,6-DIMETHYL-4-OXO-4,5,6,7-TETRAHYDROINDAZOLES IN [3+2] CYCLOADDITION REACTIONS

Abstract

The [3+2] cycloaddition reactions of a series of 1,3-substituted 5-diazo-6,6-dimethyl-4-oxo-4,5,6,7-tetrahydroindazoles with maleic anhydride and dimethyl acetylenedicarboxylate gave 1′,3′-substituted 3-spiro[4,6-dioxo-4,6,3a,6a-tetrahydro-3H-furo[3,4-c]pyrazole]-5′-[6′,6′-dimethyl-4′-oxo-4′,5′,6′,7′-tetrahydroindazoles] and 1′,3′-substituted 3-spiro[4,5-di(methoxycarbonyl)-3H-pyrazole]-5′-[6′,6′-dimethyl-4′-oxo-4′,5′,6′,7′-tetrahydroindazoles] respectively. When heated the former eliminate nitrogen and are transformed into 1′,3′-substituted 6-spiro[2,4-dioxo-3-oxabicyclo[3.1.0]hexane]-5′-[6′,6′-dimethyl-4′-oxo-4′,5′,6′,7′-tetrahydroindazoles].

How to Cite
Strakova, I.; Strakovs, A.; Petrova, M.; Belyakov, S.  Chem. Heterocycl. Compd. 2007, 43, 1512. [Khim. Geterotsikl. Soedin. 2007, 1784.]

For this article in the English edition see DOI 10.1007/s10593-007-0234-3