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Hydrazidoyl halides 1a reacted with diethylphosphonoacetonitrile (2a) in sodium ethoxide to yield the hydrazine derivative 4a which readily cyclized to form the corresponding diazaphosphole 5 . The latter was hydrolyzed to form the final product 6, with the formation of a low yield of a second product 7a . Similarly 1b, c reacted with diethylphosphonoacetonitrile and triethylphosphonoacetate 2a, b to produce the corresponding diazaphospholes 6b–d . Interaction of hydrazidoyl halides 1b, d–g with Lawesson's reagent in dry toluene produced 1,3,4-thiadiazaphosphole derivatives 10b, d, e and 11f, g respectively.

The molecular structures and spectral properties of α-haloketones as well as their syntheses are analyzed and reviewed. Their reactivity towards oxygen, nitrogen, and sulfur nucleophiles, carboxylic acids, carbon nucleophiles, alkenes, and alkynes are discussed.

The applicability and synthetic potency of the new reagent N-(2,2-dicyanoethenyl)aminoacetonitrile (3) to develop an expeditious convenient synthetic route of unique polyfunctionally substituted pyrroles, heterocyclopyrimidines, and 2H-1-benzopyran-2-ones is reported. Chemical and spectroscopic evidence for the structures of the newly synthesized compounds are described.

Describes the synthesis and testing of a group of dyes, derived from heterocyclic compounds containing thiazole ring systems. Gives a comparative analysis of the dyes’ washing, perspiration and rubbing fastness when applied to synthetic fabrics.

The applicability and synthetic potency of the reagent diethyl 2-aryl-3-phenylsulfonylpropen-l,1-dicarboxylate 3 is reported. Compound 3 proved to be a key precursor in heterocyclic sulfones synthesis. Chemical and spectroscopic evidences for the structure of the newly synthesized compounds are described.

1-Benzoyl-1-phenylsulfone-2-ethoxyethene 3 has been prepared via reaction of phenacyl sulfone 1 with triethylorthoformate. Compound 3 can be used for prepration of pyridinethione, which could be annulated into fused various heterocyclic ring systems.

The applicability and synthetic potency of the novel reagents diethyl 2-aryl-3-(phenylsulfonyl)propene-1,1-dicarboxylate 3 are reported. Compounds 3 are shown to be key precursors in heterocyclic sulfones syntheses. Chemical and spectroscopic evidence for the structure of the newly synthesized compounds are described.

The applicability and synthetic potency of novel reagent, 2-aryl-1,1-dicyano-3-(phenylsulfo-nyl)propenes 3 to develop an expeditious convenient synthetic route of unique polyfunctionally substituted carbocyclic and heterocyclic sulfone systems is reported. Chemical and spec­troscopic evidence for the structures of the newly synthesized compounds are described. Some of the obtained compounds were tested for their antimicrobial activity

Diethyl 2-phenyl-3-thiocyanopropene-1,1-dicarboxylate (3) as a key precursor in heterocyclic synthesis. The applicability and synthetic potency of 3 are studied to afford unique heterocyclic compounds.

A novel synthesis of a-substituted phosphonium ylides and pyrazole systems via the treatment of hydrazonoyl halides 1 with phosphoranes 2 and 6, respectively is reported.

An expeditious synthetic route for the title precursor is reported. It provides access to a variety of polyfunctionally substituted pyridines, pyridazines, pyrazolopyridines, thiophenes, and thienopyridines.

The applicability and synthetic potency of the novel reagent 1-aryl-1,1-dicyano-3-phenylsulfonylpropene for the development of an expeditious synthetic approach to unique polyfunctionally substituted heterocyclic sulfone systems is reported. Chemical and spectroscopic evidences for the structures of the new compounds are presented.

Several new dibenzopyrans as well as novel thiadiazaacenaphthenes are obtained via 4 + 2 addition of the thienocoumarins (1) and thienopyridazines (2) to electron-poor olefins.Key words : pyridazines, thienopyridazines, phthalazines, coumarines, thiadiazaacenaphthenes.

A new synthesis of 1,3,4-thiadiazoles has been achieved. The reactivity of certain alkylheterocycles towards electrophilic reagents are reported.

Several new alkylpyridine and pyridazine derivatives have been synthesized. The reactivity of these alkylazines towards aromatic aldehydes and sulphur are reported. New syntheses of pyrido[3,4-C]pyridines and phthalazines were achieved.

Ethyl O-alkyldithiocarbonates (1) reacted with glycine to yield the glycine thiocarboxylates (3). On heating in acetic anhydride compounds (3) afforded the 2-thiazolin-5-ones (4) which could be trapped as 4-arylhydrazones (4) and Carylidene derivatives (6). Compounds (5a,b) produced 5-oxo-1,2,4-triazoline-3-carboxylic acid derivatives (12) on treatment with amines. The arylidene derivative (6b) reacted with amines to yield the imidazolidines (17).

2-Phenyl-4-p-tolylhydrazono-2-oxazoline-5-one (3) was rearranged by the action of phenols and naphthols into 1,2,4-triazole-5-carboxylic esters (5) that were rearranged further on reflux in AcOH-ZnCl2 into triazolyl ketones (7). Rearrangement of 3 into 1,2,4-triazole derivatives could also be effected by the action of heterocyclic amines and 1-naphthylamine. © John Wiley & Sons, Inc.

Novel synthesis of α-substituted-β-enaminonitriles could be obtained from reaction of β-enaminonitriles with paraformaldehyde and dimethylamine. Such compounds reacted readily with a wide variety of reagents to give unique heterocyclic systems.

Photoexcited 1-naphthalenecarbonitrile (1) adds 2-morpholinoacrylonitrile (2) in the [2 + 2] mode both at the C(1) – C(2) and C(7) – C(8) bond unidirectionally and with the formation of only one (3 and 4, respectively) of the two a priori possible stereoisomers in each case. The structure of 3 has been unambiguously confirmed by an X-ray structural analysis.

Atroside (1), an acylated steroid glucoside, has been isolated from Perovskia atriplicifolia along with other known compounds.

The alkyl-substituted heterocyclic carbonitriles 1–3 react with elemental sulphur to yield the thienoazines 7, 11 and 13, respectively. Whereas 7 reacts with acrylonitrile to afford a [4+2] cycloaddition product with elimination of hydrogen sulphide, compounds 11 and 13 are not converted into cycloadducts. The quinoline 9a and the quinazoline 14 are obtained by reaction of 1 and 3, respectively, with formaldehyde and malononitrile. The thienopyridines 16 are produced by reaction of 6a, c with benzylidinemalonitrile. Furo[3,4-f]indazole 19 is prepared by [4 + 2] cycloaddition of the thienopyrazole 18 with maleic anhydride. The effect of the substituent of the thienyl moiety of the thienopyridazine ring system on its reactivity toward electron-poor olefins has been investigated.

Novel synthesis of α-substituted-β-enaminonitriles could be obtained from reaction of β-enaminonitriles with paraformaldehyde and dimethylamine. Such compounds reacted readily with a wide variety of reagents to give unique heterocyclic systems.

The applicability and synthetic potency of the novel reagent 1-aryl-1,1-dicyano-3-phenylsulfonylpropene for the development of an expeditious synthetic approach to unique polyfunctionally substituted heterocyclic sulfone systems is reported. Chemical and spectroscopic evidences for the structures of the new compounds are presented.

The reaction of azine-thiones with ethyl chlorofluoroacetate afforded 2-fluorothienoazines. The latter underwent self-condensation and gave multi-fused heterocyclic compounds. A wide range of unique heterocycles could be obtained on treatment of 2-fluorothienoazines with nitrogen nucleophilic reagents. The reactivity of the pyrimidine-thiones towards a variety of electrophilic reagents was studied. Chemical and spectroscopic evidence of the newly synthesized compounds are described.

The pyrazolo[3,4-b]pyridine derivatives 3 could be prepared by condensing compounds 1 with the 3-aminopyrazolone derivative 2. The pyrazolo[5,2-b]-1,3-oxazine derivative 11 and polyfunctionally substituted 1,4-dihydropyridines 15, 18 were also synthesized. Some of the obtained compounds were tested for their antimicrobial activity.

Several new dibenzopyrans as well as novel thiadiazaacenaphthenes are obtained via 4 + 2 addition of the thienocoumarins (1) and thienopyridazines (2) to electron-poor olefins.Key words : pyridazines, thienopyridazines, phthalazines, coumarines, thiadiazaacenaphthenes.

An expeditious synthetic route for the title precursor is reported. It provides access to a variety of polyfunctionally substituted pyridines, pyridazines, pyrazolopyridines, thiophenes, and thienopyridines.

The applicability and synthetic potency of novel reagent, 2-aryl-1,1-dicyano-3-(phenylsulfo-nyl)propenes 3 to develop an expeditious convenient synthetic route of unique polyfunctionally substituted carbocyclic and heterocyclic sulfone systems is reported. Chemical and spec­troscopic evidence for the structures of the newly synthesized compounds are described. Some of the obtained compounds were tested for their antimicrobial activity

The pyridine derivatives 4 and 10 are obtained by condensing β-aminocrotononitrile (1a) with malononitrile. Compound 4 affords the pyridylpyridazine 7 on coupling with aryldiazonium salts. The reaction of 1a with cyanothioacetamide affords 12 which affords the thieno[2,3-b]pyridine 13 on treatment with phenacylbromide, and pyrido[2,3-b]pyridine 15 on treatment with benzylidenemalononitrile (14). A variety of new pyridines, cyclohexadiene, and pyridopyridine derivatives were obtained from reaction of 2-amino-1-propene-1,1,3-tricarbonitrille (1b) and diethyl 3-amino-2-cyanopent-2-enedioate (1c) with Michael-systems. Reaction of 1b with acrylonitrile afforded an acyclic diadduct 25 which could be cyclized to the aminoquinoline 26. Nitrile in der Heterocycien-Synthese: Neue Wege zu polyfunktional substituierten Pyridinen, Pyridopyridinen, Chinolinen und Pyridazinen Die Pyridine 4 und 10 wurden durch Kondensation von β-Aminocrotonnitril (1a) mit Malonsauredinitril erhalten. Aus Verbindung 4 entsteht das Pyridylpyridazin 7 durch Kupplung mit Diazoniumsalzen.—Reaktion von 1a mit Cyanothioacetamid liefert 12, das seinerseits mit Phenacylbromid zu dem Thieno[2,3-b]pyridin 13 reagiert. Das Pyrido[2,3-b]pyridin 15 entsteht aus 12 mit Benzyliden-malonodinitril. Zahlreiche neue Pyridine, Cyclohexadiene und Pyridopyridine entstanden durch Reaktion von 2-Amino-1,3,3-tricyanopropen (1b) bzw. dem Diethylester der β-Amino-β-carboxymethyl-acrylsaure (1c) mit α,β-ungesattigten Carbonylverbindungen. Die Umsetzung von 1b mit Acrylnitril fuhrte zu einem Diaddukt 25, das zum Aminochinolin 26 zyklisiert wurde.