Collect. Czech. Chem. Commun. 1984, 49, 65-70

Synthesis and reactions of furocondensed derivatives

Alžbeta Krutošíková, Jaroslav Kováč and Miroslava Dandárová

Department of Organic Chemistry, Slovak Institute of Technology, 812 37 Bratislava


This paper describes the preparation of furo[2',3' :4,5]pyrollo[1,2-d]-1,2,4-triazolo[3,4-f]-1,2,4-triazines (V) from 4H-furo[3,2-b]pyrolle-5-carboxhydrazide (I, and benzo[b]furo[2',3' :4,5]-pyrrolo[1,2-d]-1,2,4-triazolo[3,4-f]-1,2,4-triazines (VIII) from 1H-benzo[b]furo[3,2-b]pyrrole-2-carboxhydrazide. Compound I reacts with triethyl orthoformate or orthoacetate to give 1,2-dihydro[2',3'-4,5]pyrrolo[1,2-d]-1,2,4-triazin-1-one or its methyl analogue II. Compounds of general formula II afford with phosphorus pentasulfide thiones III; III yields IV with hydrazine. Cyclization of IVwith triethyl orthoformate or orthoacetate furnished compounds V. Similarly, VIgives with hydrazine VII, which, upon reaction with triethyl orthoformate or orthoacetate affords VIII.