Synthesis and comparative study of reactivities of δ-lactone,estor group and oxazinone ring in coumarin derivatives towards carbon or nitrogen nucleophiles

查看全文 作　　者：EL-KAFRAWY,A.F. SOLIMAN,A.Y. BAKER,H.M. MOHAMED,F.K. EL-KADY,M.Y.Department of Chemistry,Faculty of Science,Ain Shams University and Faculty of Education at El-Fayoum,Cairo.Egypt 出　　处：《Chinese Journal of Chemistry》索引1990年第8卷第5期,共2页 摘　　要：Condensation of methyl 7-methylcoumarin-4-acetate(2)with primary amines and with an-thranilic acid gave 7-methyl-2-oxo-N-aryl-2H-[1]-benzopyran-4--acetamide(4a—d)and(7),respectively.Compound 7 underwent cyclization to give 2-(7-methyl-2-oxo-2H-[1]-benzopyran-4-yl)-methyl-4H-3,1-benzoxazin-4-one(3).The reaction of 3 with aromatic amines gave the corresponding quinazolonederivatives 5 which tautomerises to the thermodynamically more stable isomer 6,whereas its reactionwith Grignard reagents and aromatic aldehydes gave 8a,8b,and 9a,9b,respectively. 关 键 词：LACTONE COUMARIN aromatic aldehydes AMINES CYCLIZATION deriv amide CARBONYL readily