Pergamon PII: S0040-4020(97)00088-4 Tetrahedron, Vol. 53, No. 10, pp, 3649-3658, 1997 © 1997 Published by Elsevier Science Ltd All rights reserved. Printed in Great Britain 0040-4020/97 $17,00 + 0.00 Studies on Phosphonium Ylides XXIL Reactions of Wittig Reagents with Substituted 2-Amino- 1,4-Naphthoquinones Leila Sadek Boulos* and Mona Hizkiai Nasr Arsanious Department of Pesticide Chemistry, National Research Centre, Dokki, Cairo, Egypt Abstract : The reaction of methoxycarbonylmethylene 2b- and ethoxycarbonylmethylene 2e-triphenylphosphoranes with substituted 2-amino-l,4- naphthoquinones la-c afforded the new p>rroline-ylidphosphoranes 3b-3g via 1,2- and 1,4-addition reactions. On the other hand, 2-dimethylamino-l,4-naphthoquinone ld reacts with cyanomethylenetriphenylphosphorane 2d to give adduct 4. Mechanisms accounting for the formation of the new prevJucts are discussed. © 1997Publishedby ElsevierScienceLtd. All rights reserved. INTRODUCTION It has been reported 2 that 2-anilino-l,4-naphthoquinone lc reacts with benzylidene- triphenylphosphorane 2a yielding the respective quinonemethide 3a and triphenylphosphine oxide (Scheme 1). 0 I ^.,'C6H5 / N__C6H5 I-1 ~H--C6H5 > --C6H5 + p(CsHs) 3 0 lc 2a 0 Scheme 1 3a + Ph PO 3 Our continuing interest in the reaction of phosphonium ylides for the production of novel, synthetically useful ylides and new heterocyclic systems, 1,3-11 led us to examine the behaviour of substituted 2-amino-l,4-naphthoquinones la-d toward some phosphonium ylides 2b-2d. *To whom correspondence should be addressed. 3649