Collect. Czech. Chem. Commun. 1997, 62, 99-108

Gould-Jacobs Reaction of 5- and 6-Amino-2-substitutedBenzoxazoles. III. Reaction with 3-Ethoxy-2-cyanopropenonitrile and Ethyl 3-Ethoxy-2-cyanopropenoate

Katarína Heleyováa and Dušan Ilavský

a Research Institute of Drugs, 900 01 Modra, Slovak Republic


Nucleophilic reaction of 5-amino- (1) and 6-amino-2-substituted benzoxazoles (2) with 3-ethoxy-2-cyanopropenonitrile (3) afforded the respective benzoxazolylaminomethylenemalononitriles 5 and 6. The amino derivatives 1 and 2 reacted with ethyl 3-ethoxy-2-cyanopropenoate (4) to give the corresponding esters of benzoxazolylamino-2-cyanopropenoic acid 7 and 8, respectively. The products 7 on thermal cyclization at 250-260 °C in a mixture of diphenyl ether and biphenyl afforded a mixture of angularly and linearly annelated 5-nitrile-4-oxooxazolo[4,5-f]quinoline 9 and 7-nitrile-8-oxooxazolo[5,4-g]quinoline 10; under the same conditions compounds 8 were converted into 8-nitrile-9-oxooxazolo[5,4-f]quinolines 11 and 6-nitrile-5-oxooxazolo[4,5-g]quinolines 12.

Keywords: Gould-Jacobs reaction; Oxazoloquinolones.