Synthesen von Heterocyclen, CCVIII [1]. Zur Chemie der vicinalen Triketone, XI [2]. Ringverengungsreaktionen von Chinolintrionen / Syntheses of Heteroeycles, CCVIII [1]. The Chemistry of Vicinal Triketones, XI [2]. Ringcontractions of Quinolinetriones

Abstract

1,2,3-Trioxo-2,3,6,7-tetrahydro-1 H,5H-benzo [ij] quinolizine (I) does not react with 2-aminopyridine to give a Schiff base [2], but reacts by ringcontraction to the spiroindolone 1/I, which can be hydrolysed to 1-(2-pyridyl-amino)1,2,5,6-tetrahydro-4 Hpyrrolo[ 3,2,1-ij]quinoline-2-one (2/1). In the same way the reaction of I resp. 1-phenylquinolinetrione (II) with tert-butylamine in aliphatic alcohols yields by ringcontraction the indolone acid esters 5 a-c. Reaction of I with tert-butylamine without solvent forms the ringcontracted amide 5c/I.