Syntheses of spiro[cyclopropane-1,3'-oxindole]-2-carboxylic acid and cyclopropa[c]quinoline-7b-carboxylic acid and their derivatives

Authors

Sarah Yong, University of WollongongFollow
Alison T. Ung, University of WollongongFollow
Stephen G. Pyne, University of WollongongFollow
Brian W. Skelton, University of Western Australia
Allan H. White, University of Western Australia

RIS ID

19187

Publication Details

Yong, S. R., Ung, A. T., Pyne, S. G., Skelton, B. W. & White, A. H. (2007). Syntheses of spiro[cyclopropane-1,3'-oxindole]-2-carboxylic acid and cyclopropa[c]quinoline-7b-carboxylic acid and their derivatives. Tetrahedron, 63 (5), 1191-1199.

Abstract

The synthesis of spiro[cyclopropane-1,3′-oxindole]-2-carboxylic acid, including novel 3-(2- and 3-pyridyl)-substituted analogues and the novel cyclopropa[c]quinoline-7b-carboxylic acid and their ester and amide derivatives is described. These syntheses involve diastereoselective cyclopropanation reactions of methyl 2-(2-nitrophenyl)acrylate and (3E)-(pyridin-2-ylmethylene)- and (3E)-(pyridin-3-ylmethylene)-1,3-dihydro-2H-indol-2-one with ethyl (dimethyl sulfuranylidene) acetate (EDSA). The synthesis of methyl cyclopropa[c]quinoline-7b-carboxylate involves a regioselective reductive cyclization of a nitro-diester precursor. The relative stereochemistry of key compounds has been determined by single-crystal X-ray structural analysis.