A novel protocol for the synthesis of indolone and quinolone derivatives from o-nitroaryl acids was developed using Zn and HCO2NH4 under supercritical fluid carbon dioxide (scCO2) medium. The process involves the reduction of the nitro group to an amino group followed by in situ cyclisation.
GribbleG.W., J. Chem. Soc., Perkin Trans.1, 2000, 1045.
2.
SaxtonJ.E., The chemistry of heterocyclic compounds: indoles, Wiley-Interscience, New York, 1983 Vol. 25, Part IV.
3.
RanjanBabuT.V.R., ChenardB.L., and PettiM.A., J. Org. Chem., 1986, 51, 1704.
4.
CorteseN.A., and HeckR.F., J. Org. Chem., 1977, 42, 3491.
5.
QuallichG.J., and MorrisseyP.M., Synthesis., 1993, 51.
6.
SimetL., J. Org. Chem., 1963, 28, 3580.
7.
SrinivasaG.R., NalinaL., AbirajK., and GowdaD.C., J. Chem. Res. (S)., 2003, 630.
8.
GowdaS., AbirajK., and GowdaD.C., Tetrahedron Lett., 2002, 43, 1329.
9.
GowdaD.C., MaheshB., and GowdaS., Indian J. Chem., 2001, 40(B), 75.
10.
BaikerA., Chem. Rev., 1999, 99, 453.
11.
PrajapatiD., and GohainM., Tetrahedron., 2004, 60, 815.
12.
RodeC.V., JoshiU.D., SatoO., and ShiraiM., Chem. Commun., 2003, 1960
13.
SubramanianB., and MaCoyB.J., J. Ind. Eng. Chem. Res., 1994, 33, 504.
14.
SubramanianB., and TormaA., Innovations in supercritical fluids science and technology; ACS Symposium Series No. 608; HutchensonK.W., and FosterN.R., (eds) American Chemical Society, Washington DC, 1995. p. 246.
15.
BoixC., de la FuenteJ.M., and PoliakoffM., New J. Chem., 1999, 23, 641.
16.
SumpterW.C., Chem. Rev.1945, 37, 443.
17.
GoetzE.H., US pat.1979, 4,160,032.
18.
MichaelE.C., and GaryM.K., US pat.1993, 5,252,536.