الفهرس 
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Abstract
The aim of this study is the synthesis of some heterocyclic compounds by using linear compounds as electron donors and some n-deficient compounds. Electron donors are used as following:
(Ia) 4-Phenylthiosemicarbazide. (lb) 4-Benzylthiosemicarbazide. (Ie) 4-Allylthiosemicarbazide.
(Id) 4-(4-Fluorophenyl)thiosemicarbazide.
(I e) 4-(3,5- Di fluoropheny l)thiosemicarbazide.
(It) 4-[ 4-(Trifluoromethy l)pheny I ]thiosemicarbazide.
(2a) N- Phenyl- 2 [( E)- 3 - pheny lallylidene ]hydrazinecarbothi oamide. (2b) N-Benzyl-2[ (E)- 3-phenylallylidene ]hydrazinecarbothioamide. (2e) N- Allyl- 2 [( E)- 3 -pheny lallylidene ]hydrazinecarbothioam ide.
(2d) 2-( E)- 3 -[ (2- Methoxypheny I)ally lidene ] - N- pheny Ihydrazinecarbothioamide. (2e) N- Benzyl- 2 -( E)- 3 - [(2- methoxypheny I)ally lidene ]hydrazinecarbothioam ide. (2t) N- Allyl- 2-( E)- 3- [(2 -m ethoxyphenyl )allylidene ]hydrazinecarbothioam ide. (2g) 2-(E)- 2- Methy 1- 3 -phenylallylidene- N- pheny Ihydrazinecarboth i oamide.
(2h) 2-(E)- Hex - 2-enylidene-N-pheny Ihydrazinecarbothioam ide.
(2i) N- Benzy 1- 2-( E)-hex - 2-eny lidenehydrazinecarbothioam ide.
(2j) N- Allyl- 2-( E)- hex - 2-enylidenehydrazinecarbothioam ide.
(2k) 2-(E)- B ut- 2-eny I idene- N-phenylhydrazinecarbothioamide.
Study of Chemical Interaction between Thiosemicarbazides and ~·Deficient Reagents
1.1. Reactions between 4-substituted thiosemicarbazides la-f and (1,32,3-dihydro-l(H)-indene-2-ylidene )propanedinitrile (CNIND, 3)
Solutions of 3 and substituted thiosemicarbazides la-f in ethyl acetate with a molar ratio of 1:1 were refluxed for 3-6 hrs. Concentration of the reaction mixture yielded reddish brown crystals from N-substituted-5’ -amino-4’ -cyano-l ,3-dioxo-l ,3pyrazole]-2’(I’H)-carbothioamides 6a-f (63-71 %). The remaining soluble materials were subjected to preparative layer chromatography to give 4e]triazine-9(4H)-ones 7a-c,e,f(17-26 %) (Scheme I).
The formation of 6 and 7 indicate that thiosemicarbazides la-f react with 3 through a nucleophilic attack of terminal amino group la-f to the C=N triple bond of 3 to form the intermediate 8, compound 8 exerts its nucleophilic character and intramolecular nucleophilic attack ofNH to the C=C douple bond, where the electron-withdrawing groups (two carbonyl and one nitrile groups) facilitate this reaction to form the products 6a-f. On the other hand, nucleophilic attack of la-f to C=C double bond of 3 and elimination a molecule of malononitrile afforded the formation of intermediate 9. Nucleophilic attack of NH to the carbonyl group followed by elimination H20 gave thioxoindenotriazines 7a-c,e,f (Scheme 2).