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The chemoselectivity of the title reaction is shown to be depending on the type of the utilized hydrazonoyl halide.

Title compounds (III) are prepared in high yields via a cascade Knoevenagel—Michael condensation followed by cyclodehydration utilizing SiCl4 as catalyst.

A solvent-free, environmentally clean, mild, and simple one-pot multi-component protocol has been developed for the efficient synthesis of 1-amido- and 1-carbamato-alkyl naphthols/phenols in excellent yields via one-pot three-component condensation of various aldehydes, amides/carbamates/urea, and naphthols/phenols using ethylammonium nitrate (EAN) as a reusable ionic liquid catalyst under neat reaction condition at ambient temperature.

The solvatochromic and substituent effects on the absorption spectra of azo dyes (III) are interpreted by correlation of absorption frequencies with Kamlet—Taft and Hammet equations, respectively.

The review includes synthetic methodologies of dithiocarbamic acid salts, their S-substituted derivatives, and nano particles (NP's) in their synthesis. This review also deals with the utility of dithiocarbamates in synthesis of: (a) heterocycles, (b) some organic reagents and (c) NP's.

Ashraf A. Aly,* Esam A. Ishak, Musaed A. Alsharari, Nayef S. Al-Muaikel, and Tarek M. I. Bedair Chemistry Department, Faculty of Science, El-Minia University, 61519 El-Minia, Egypt Chemistry Department, College of Science, Al-Jouf University, Al-Jouf, Sakaka, Saudi Arabia Chemistry Department, Faculty of Science, El-Azhar University, Assiut, Egypt Chemistry Department, College of Pharmacy, Al-Jouf University, Al-Jouf, Sakaka, Saudi Arabia *E-mail: ashrafaly63@yahoo.com Received May 7, 2010 DOI 10.1002/jhet.639 Published online 18 October 2011 in Wiley Online Library (wileyonlinelibrary.com).

No desired product is obtained by the reaction of compound (I) with phthalaldehyde under this reaction conditions.

Combinations of N-halosuccinimide and tetrachlorosilane in acetonitrile were found to be efficient systems for the selective α-monohalogenation of carbonyl compounds as well as for benzylic halogenation under mild conditions.

Some of the new adamantylthiadiazole derivatives, e.g. (II), (IXa), (IXc), (XIIIb), and (XIIIc) display marked antibacterial activities.

The synthesis of different 3-acetamido-coumarin-6-sulphonylamino acids 2a-e; corresponding methyl esters 3a-e; dipeptides 4a-e and some related 3-amino or 3-hydroxy derivatives 5a-6d are described. All the 3-amino or 3-hydroxycoumarin-6-sulphonylamino acid derivatives were found to possess remarkable antimicrobial properties towards different microorganisms.

The intrazeolite Aul in NaY zeolite exhibits remarkable catalytic activities in the decomposition of NO to N2(N2O) and O2 at low temperatures; the NO decomposition reaction proceeds through the sequential formation of N2O3 and N2O intermediates on Aul/NaY at 300–673 K.

The selective reduction of NO with CO in the presence and absence of hydrogen over Au/NaY catalysts has been studied by in situ FTIR spectroscopy and under steady-state conditions in a flow mode in the temperature range 473–723 K. The NCO intermediates found by FTIR absorption at 2280–2240 cm–1 after contacting, at 423–573 K, an Au/NaY catalyst with an NO–CO–H2 mixture shows a dependence on the presence of H2 which functions in N—O dissociation in this temperature region. Removal of NCO groups from the catalyst with time at 473 K, proposed to be limited by the prerequisite reaction between adsorbed NCO and NO in the gas phase, to form N2 and CO2 is accelerated with increasing temperatures. The effect of adding H2 to an NO–CO–He stream on the conversions of both NO and CO to, respectively, N2 and CO2 were found to be consistent with a temperature-dependent mechanism. The yields of N2 and CO2 were increased in the presence of hydrogen, when NCO complexes were present on the gold catalyst, up to 573 K. Above this temperature, where direct NO + CO is the only competing reaction, the presence of hydrogen reduced conversion. The activities of the gold catalysts were maintained even at temperatures as high as 723 K, suggesting that a large fraction of partially charged AuI cations were stabilized by the framework of NaY zeolite. This species, after pumping off the reacting mixture gases at 473 K and collecting the spectra on cooling the gold catalyst, gave a characteristic carbonyl IR absorption band at 2188 cm–1, reasonably assigned to a CO vibration of carbonyl coordinated to AuI.

A significant enhancement of the selective reduction of nitrogen oxide by H 2 is produced in the presence of oxygen over Au/NaY and Au/ZSM-5 catalysts by forming NO 2 and N 2 O 4 intermediates, which are eventually reduced to N 2 .

Acetoacetanilide 1 reacted with DMF-DMA to give the enaminone 2. Compound 2, when treated with hydrazines gives the pyrazoles 4a and 4b respectively, and with pyrazole derivatives Sa and 5b the pyrazolopyrimidines 7. On the other hand, in reaction of 2 with benzimidazole and benzimidazole-2-acetonitrile, the pyrimidobenzimidazole 14 and the pyridobenzimidazole 17 were formed. 2 reacts with hippuric acid in boiling acetic anhydride to afford the pyridine 20. In the reaction of 2 with malononitrile, cyanoacetamide or malononitrile dimer compounds 21, 22 and 24 were formed. Compound 22 was further reacted with arylidenemalononitriles to give the benzopyridine derivatives 28. Pyridone 22 treated with S-DMF mixture gives thienopyridine 29, while refluxed with DMFDMA yielded the pyridopyridine 30.

A series of 3-aryl-2-thioxoquinazolin-4(3H)-ones 1a-g are prepared in good yields from reactions are prepared in good yields from reactions of anthranilic acids, aromatic amines and carbon disulfide under basic conditions in one step. Reaction of aminophenyl derivatives 1a,b with D-glucose affords the corresponding N-glucosylamines 4a,b in very good yields. Diaztoziation of 1a,b followed by reactions with aromatic amines yield the corresponding azo dyes 6a-f in 40-56% yields. The fastness of 6 has been studied. Compounds 6a,b,f have been proved to be biologically active.

2-Allyl-3-benzylamino-2-cyclohexenones undergo iodine-methanol-promoted iodocyclisation under reflux to afford products characterised by combination of NMR ( 1 H and 13 C), IR and mass spectroscopic techniques as the conjugated iodolium betaine derivatives of 2-iodomethyltetrahydroindolones. The zwitterionic nature of the products in solution and in the solid state was also confirmed by their chemical behaviour and the experimental data were corroborated by information from quantum chemical calculations.

Reaction of 1-adamantanecarbonyl chloride with certain carboxylic acid hydrazides in pyridine yielded the corresponding N-acyl adamantane-1-carbohydrazide derivatives 3a-j, which were cyclized to the corresponding 2-(1-adamantyl)-5-substituted-1,3,4-oxadiazoles 4a-j via heating with phosphorus oxychloride. Treatment of 1-adamantylisothiocyanate with some carboxylic acid hydrazides in ethanol yielded the corresponding 1-acyl-4-(1-adamantyl)-3-thiosemicarbazides 7a-g, which were cyclized to the corresponding 2-(1-adamantylamino)-5-substituted-1,3,4-thiadiazole derivatives 8a-g. Compounds 4a-j, 7a-g, and 8a-g were tested for in vitro activities against a panel of Gram-positive and Gram-negative bacteria and the yeast-like pathogenic fungus Candida albicans. Several derivatives produced good or moderate activities particularly against the tested Gram-positive bacteria Bacillus subtilis. Meanwhile, compounds 4i and 8g displayed marked antifungal activity against C. albicans. In addition, the in vivo anti-inflammatory activity of the synthesized compounds was determined using the carrageenin-induced paw oedema method in rats. The oxadiazole derivatives 4c, 4g, 4i and 4j produced good dose-dependent anti-inflammatory activity.

On heating of the cyanoacetic acid cyclopentylidene hydrazide 1 with salicylaldehyde in the presence of bases the azaanthracene derivative 6 was formed. Also, reaction of 3 with malononitrile and ketones 10a,b afforded the pyrano[3,4-c]chromene 9 and chromeno[3,4-c]pyridine 11 respectively. A mechanism for these reactions is proposed.

The enaminone 2 reacts with 5-aminopyrazole derivative 3 and 2-aminobenzimidazole 5 in refluxing acetic acid to afford the diazacyclopentafluorene derivative 4 and the triazaindenofluorene derivative 6 respectively. Also,2 reacted with benzamidine hydrochloride hydrate 7 in dry pyridine to give the indenopyrimidine derivative 8. The reaction of 2 with lH-benzimidazole-2-yl-acetonitrile 9, 4-cyanoacetylphenazone 11 and malononitrile, yielded the indenofluorene 10, indenopyran 12, and fluorenone 13 respectively.

The hydrazone 1 reacts with DMFDMA to give 2-dimethylaminomethylene-3-(phenylhydrazono)-indan-1-one (2) which reacts with hydrazine hydrate and the pyrazole derivative 4 to afford the indenopyrazole derivatives 3 and the indenofluorene 5 respectively. The reaction of 2 with the active methylene compounds, mainly malononitrile, cyanoacetamide and malononitrile dimer was investigated and found to proceed successfully to yield the indenopyran 7, indenpyridine 8b and trinitrile 9 respectively. Compound 2 reacted with lH-benzimidazole-2-acetonitrile 10 to give to the diazaindenofluorene derivative 11. Also, 2 reacted with ω-cyano compounds 12a,b to afford the indenopyran 14. On the other hand the hydrazone 1 was allowed to react with the enaminones 15, 18 and 21 affording the diazabenzoazulene derivatives 17, 20 and the indeno[1,2-b]pyridin 23, respectively.

The reaction of 6-hydrazinopyrimidine-2,4-dione derivative 1 with alkyl or aryl isocyanates 2a-d resulted in a novel and facile synthesis of pyrazolo[3,4-d]pyrimidine derivative 5a-d in good yield.