A simple and facile method for the synthesis of novel 5/7 trifluoromethyl-substituted 4(3H)-quinazolone regioisomers
作者:D. Maitraie、G. Venkat Reddy、V.V.V.N.S. Rama Rao、S. Ravi Kanth、P. Shanthan Rao、B. Narsaiah
DOI:10.1016/s0022-1139(02)00194-x
日期:2002.12
The unsymmetrical 1,3-diketones 1 on reaction with malononitrile is resulted an interesting trifunctional intermediates 2 and 3. The intermediate 2 is hydrolyzed to give 2,6-dicarboxamido aniline 4 which on cyclisation gave two regioisomers of 1,2-dihydro-4(3H)quinazolinones 5 and 6. The effect of substituents on compound 4 is characteristic for formation of regioisomers in different proportions. Each regioisomer on dehydrogenation under mild condition using active MnO2 gave corresponding 4(3H)-quinazolones 7 and 8, respectively. (C) 2002 Elsevier Science B.V. All rights reserved.