الفهرس 
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Abstract
This thesis aims to synthesize novel heterocyclic compounds via conventional, click reaction and MW methods. Thus it is divided into seven parts:
Part 1:
It deals with studying the interactions between electron rich compounds as 2-aminobenzohydrazide (1a) with tetracyanoethylene (TCNE, 294), 2-dicyanomethylene-indan-1,3-dione (CNIND, 296), 2,3-dicyano-5,6-dichloro-1,4-benzoquinone (DDQ, 302), 2,3,5,6-tetrabromo-1,4-benzoquinone (304), 2,3-dichloro-1,4-naphthoquinone (DCHNQ, 306) and 1,4-naphthoquinone (NQ, 308).
Firstly, We have found that on treatment of 2-aminobenzohydrazide (1a) with teteracyanoethylene (TCNE, 294) in dry ethyl acetate at room temperature led to the formation of 5-oxo-4,5-dihydro-1H-benzo[e][1,2,4]triazepine-2,2(3H)-dicarbonitrile (295) (Scheme 93).
A mechanism proposed for the formation of compound 295 is shown in Scheme 94.
On the other hand, the product 2-(5-oxo-1H-benzo[e][1,2,4]triazepin-2(5H)-ylidene)-1H-indene-1,3(2H)-dione (297) was obtained on treatment of 1a with CNIND (296) as shown in scheme 93.
The suggested mechanism for formation of the product 297 is as shown in Scheme 95.
However, on treatment of 1a with either 2,3-dicyano-5,6-dichloro-1,4-benzoquinone (DDQ, 302), 2,3,5,6-tetrabromo-1,4-benzoquinone (304), 2,3-dichloro-1,4-naphthoquinone (DCHNQ, 306), and/or 1,4-naphthoquinone (308) in ethyl acetate at room temperature afforded 1,2,5-triazocine derivatives 303, 305, 307 and 309, respectively, Scheme 96.
Part 2:
This part is focused on the study of the reaction of 2-aminobenzohydrazide (1a) with some selected carbonyl compounds such as terephthalaldehyde (310), 4-formyl[2.2]para-cyclophane (311), N-benzylpiperidone (165e), indane-1,2,3-trione (183), cyclohexane-1,2-dione (317), and dimedone (198a) as well as tetrabromophthalic anhydride (TBPA, 323) and pyromellitic dianhydride (PMDA, 325). We have found that, condensation of 1a with terephthalaldehyde (310) in the presence of a catalytic amount of iodine in boiling ethanol afforded hydrazones 311 and 312 depending on the molar ratios of 1a. While, condensation of our target 1a with 4-formyl [2.2]paracyclophane (313) under the same reaction conditions furnished hydrazone 314 as shown in Scheme 97.
The reactivity of 1a towards ketones 165e, 183, 198a and 317 has been also studied to give spiro quinazolines 315, 316, 318 and 319 as shown in scheme 98.
Scheme 99 outlines the rational pathway for the formation of the product 315.
The synthesis of 1,2,3,4-tetrabromo-5H-phthalazino[1,2-b]quinazoline-5,8(6H)-dione (324) and N,N’-(1,3,5,7-tetraoxopyrrolo[3,4-f]isoindole-2,6-(1H,3H,5H,7H)-diyl)bis(2-aminobenzamide) (326) from the reaction of the target 1a with tetrabromophthalic anhydride (TBPA, 323) and pyromellitic dianhydride (PMDA, 325), respectively as shown in scheme 100.
The suggested mechanism for formation of the product 324 is as shown in scheme 101.
Part 3:
We report herein a general, rapid, and effective procedures for the synthesis of thiazole derivatives by the reaction of N-amidinothiourea (119a) with some selected π-acceptors such as tetracyanoethylene (TCNE, 294), 2,3-dicyano-1,4-naphthoquinone (DCNQ, 332), 2,3,5,6-tetrabromo-1,4-benzoquinone (BHL-p, 304), 2,3-dichloro-1,4-naphthoquinone (DCHNQ, 306) to give the products 331, 333, 334, 335 in good yields (Scheme 102).
The rational pathway for the formation of thiazole derivative 331 is illustrated in scheme 103.
On the other hand, on treatment of 119a with either 2,3,5,6-tetrachloro-1,4-benzoquinone (CHL-p, 339), 2,3-dicyano-5,6-dichloro-1,4-benzoquinone (DDQ, 302) and 2-dicyanomethyleneindan-1,3-dione (CNIND, 296) to afford the thiazole derivatives 340, 341 and 342, respectively as shown in Scheme 104. In addition (E)-1-(5’-cyano-2-oxospiro-[indoline-3,4’-thiazolidin]-2’-ylidene)guanidine (343) was formed on treatment of 119a with the yilidine 202a.
In continuation of our study, we examined reaction of N-amidinothiourea (119a) with dimethyl acetylenedicarboxylate (DMAD, 344) in the presence of p-toluenesulfonic acid (p-TSA) to give methyl 2-((diaminomethylene)amino)-4-oxo-4H-1,3-thiazine-6-carboxylate (345) as shown in Scheme 105.
Condensation of 119a with o-phthalaldehyde (31) ”in ethanol under reflux conditions” led to the formation of 2-imino-2,3-dihydro-[1,3,5]triazino[2,1-a]isoindole-4(6H)-thione (347) (Scheme 106).
Rational pathway for the formation of compound 347 is as shown in scheme 107.
Scheme 107
Part 4:
As part of our continuing efforts on the development of new routes for the synthesis of biologically active heterocyclic compounds, we have already here reported the procedure for the synthesis of spiropyran and spiropyridine derivatives by the reaction of ninhydrin, malononitrile and active methylene compounds or activated phenols in the presence of a catalytic amount of diammonium hydrogenphosphate (DAHP) which acts as an ideal catalyst in aqueous medium at room temperature.
Thus, spiro derivatives 355,357 were prepared by the reaction of ninhydrin (183) with malononitrile (186a) and 2-cyano-N-(o-tolyl)acetamide (354) or 2-cyanoethane-thioamide (356) in the presence of a catalytic amount of DAHP which acts as an ideal catalyst in aqueous medium at room temperature (Scheme 108).
These interesting results promoted us to extend the protocol for the synthesis of spiropyran. We repeated the previous reaction following the same methodology using another active methylene compounds such as dimedone (198a) or 2-thiobarbituric acid (198b) producing spiropyran (358) or (359) (Scheme 108).
Based on the above results we extended this procedure for the synthesis of different fused spiropyran derivatives. Thus, ninhydrin (183) reacted with 186a and activated phenols to give the corresponding spiropyrans 361, 363, 365 and 367 respectively using the same catalyst in aqueous medium (Scheme 109).